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View of Auvers-sur-Oise is the common English name for a Paul Cézanne painting known by various French names, usually Paysage d'Auvers-sur-Oise, or in the artist's catalogue raisonné, Groupe de maisons, paysage d'île de France. It is believed to have been painted in 1879–80, several years after Cézanne's residence in Auvers-sur-Oise, a small village northwest of Paris. The painting depicts a landscape of Northern France; the exact location has not been determined. Victor Chocquet bought the painting from the artist, and it remained in his family's collection until the early 20th century. Later it came into the possession of Bruno Cassirer, who loaned it to the Kunsthaus Zürich. It was inherited by Cassirer's daughter Sophie, and after her death in 1979 it was accepted in lieu of inheritance tax and allocated to the Ashmolean Museum at Oxford University.Shortly after midnight on New Year's Day 2000, guards at the Ashmolean, responding to a fire alarm, discovered the painting was missing. Police believe the thief or thieves used a smoke bomb and that night's millennium celebrations as a cover for the theft of the museum's only Cézanne and the only painting taken. It has not been recovered. Description The oil-on-canvas painting depicts a rolling landscape below a blue sky filled with clouds, represented as smears of paint. Down a green slope from the viewer are a group of houses, white with roofs either blue or orange, again not depicted in detail. Scattered among them are trees, most green, but some with more yellowish color apparent. In the background another hillside with houses amid trees rises; a church spire rises at the crest.The location of the landscape depicted in the painting is unknown. The painting is 46 centimetres (18 in) high by 55 centimetres (22 in) wide. Cézanne's signature is in red paint at the lower left. History Camille Pissarro, whom Cézanne came to see as both friend and mentor, moved to Pontoise, a small country town northwest of Paris, in 1872 after his previous country residence in Louveciennes, west of Paris, was stripped of all its contents while he was in Paris during the Franco-Prussian War two years earlier. The following year, Cézanne moved to neighboring Auvers-sur-Oise, where he and Pissarro lived within walking distance of each other, and often painted side by side in plein air. They painted the same subjects, but in different and distinctive works.The two were trying to capture the "perception of sensation" in their work. Cézanne's style, especially in his landscapes, reflected the influence of his fellow artist, even as the two preferred different techniques—Pissarro dabbing while Cézanne daubed or smeared, according to a local resident who watched them both paint. Cézanne began using brighter colors than he had previously, with less stark contrasts.A catalogue to a 2006 joint exhibition of their work from this period at the Musée d'Orsay in Paris calls the two Impressionism's "painters of the earth", counterparts to its two "painters of water", Claude Monet and Alfred Sisley. But "with Cézanne the spectator is openly invited to observe the way he portrays surfaces" the catalog observes. "Shapes are simplified and each brushstroke is amplified. His paintings are intense reflections of his method."View of Auvers-sur-Oise was painted later, in 1879–80. By this time, Cézanne was preparing to leave Paris and return to his native Aix-en-Provence, where he continued painting in this style, including similar landscapes, moving toward Post-Impressionism. Ashmolean Museum director Christopher Brown describes the painting as important to understanding the artist's career, showing him transitioning from his early work to the mature style he brought to well-known later works. Provenance French bureaucrat Victor Chocquet, a collector and advocate for Impressionism, bought the painting. After his death in 1891, it was bequeathed to his wife Marie. In 1899 the Chocquet collection was exhibited at Galerie Georges Petit in Paris, under the title Auvers. In turn it was purchased by another collector of Impressionist works, Thadée Natanson.Natanson auctioned his collection, including View of Auvers-sur-oise, at the Hôtel Drouot in 1908. It passed that way to another prominent collector, German publisher Bruno Cassirer. He loaned it to his cousin Paul for a 1921 Berlin exhibit of Cézanne works in private German collections; it was titled Ansicht an Aix. Bruno made the painting part of an extended loan to the Kunsthaus Zürich, which exhibited it in 1933 as Regenlandschaft. On another loan to a Swiss museum, the Kunsthalle Basel. This time it was known as Bei Auvers. Bruno's daughter Sophie inherited it after his death in 1941, by which time the family had moved to Oxford following Nazi persecution. She kept it in the family's hands and did not loan it out. Upon the deaths of her husband Richard Rudolf Walzer in 1975, followed by her own four years later, the estate incurred a large inheritance tax bill. The painting was accepted by the British government in lieu of inheritance tax to become part of the collection at the Ashmolean, which lists it in its catalogue under the English title A View of buildings in a valley in the Ile-de-France. In 1998 the Ashmolean loaned it to the Art Gallery of New South Wales, in Sydney, for its Classic Cézanne exhibit; in this it was given the French title Groupe de maisons, paysage d'île de France, the title used in the artist's current catalogue raisonné. Theft At midnight on 31 December 1999, fireworks went off in Oxford as part of the global millennium celebrations that year. Police believe that at that time, someone used the distraction and noise to prevent anyone from noticing that they were climbing scaffolding around an extension to the museum's library that was under construction. Once they reached the roof, they broke a skylight over the museum's Hindley Smith Gallery and dropped a small smoke bomb in.The burglar carried with them a small holdall holding a scalpel, tape, gloves and portable fan. They dropped a rope ladder into the gallery and descended. Once there they used the fan to blow the smoke around so neither the museum's security guards, should they come into the gallery, nor its CCTV cameras would be able to get a good view of their faces. After cutting View of Auvers-sur-Oise from its frame, they smashed the empty frame on the floor, climbed the rope ladder, went back down the scaffolding and out into the crowds still celebrating the new year and millennium.Alarms had been set off during the burglary, but security at the museum assumed from the smoke that there had been a fire. When police and firefighters reached the museum at 1:43am, they went into the Smith Gallery and found the smoke had dissipated, with no signs of a fire. Instead what was left of the smoke bomb was on the floor, and a flashing light on the wall alerted them to the absence of the Cézanne painting next to it.Director Brown, in London for the millennium celebrations, was alerted within the hour. He went immediately back to Oxford and saw the crime scene for himself. "It was like coming into your own house and finding evidence of a break-in," he said. "Any director builds up an intense relationship with the works of art that he or she is responsible for, and this was very personal to me."Police soon determined that View of Auvers-sur-Oise was the only work taken from a room that also displayed paintings by Renoir, Rodin and Toulouse-Lautrec. This led them to theorise that the burglary had specifically targeted the painting, the only work by Cézanne in the Ashmolean. The thief or whoever they were working for had wanted it for a personal private collection. They may also have been motivated by the £18.2 million sale at Sotheby's of a Cézanne still life, Bouilloire et fruits, itself recently recovered following a theft in 1978, and hoped to make a similar profit. Katrina Burrows, editor of the London-based magazine Trace, which covers stolen art, doubted the thieves or anyone working for them would be able to sell the painting, if that was their goal, due to the considerable publicity surrounding the theft.The Ashmolean valued the painting at £3 million. Like other artwork in British museums, it was not insured due to the high premiums required. Burrows also said that contrary to public perception of art theft as prevalent due to the recent box office success of The Thomas Crown Affair, it had actually become much rarer due to increased security and awareness of which works might have been stolen. "Anyone offered this painting will walk over to the shelf and look it up in a Cezanne book, and would see where it belongs", Brown said.There had been other thefts and attempted thefts of art from the museum and other Oxford facilities in the late 1990s. A pair of 17th-century French bottles were taken in 1996, and the following year three thieves were caught after they broke open a glass display case to take a jewel made for Alfred the Great. Brown said the museum had not relaxed its security for the holiday.The theft also drew comparisons to another recent film, Entrapment, in which the characters use the millennium celebrations as cover for an art theft. Investigators said the thief demonstrated a high level of skill. "It was a very clever ploy, a very professional theft", an unnamed police source told The Guardian. "Whoever has taken this painting has given some thought to how to steal it" agreed Oxford police superintendent John Carr.Novelist Iain Pears, who lived nearby, said that he could have been a witness. "If I had been there 10 minutes earlier, I could have helped them load it into the car", he joked to The New York Times. He called the theft "jolly brilliant". He believed it was likely that the painting would be recovered. "Twenty years ago the Ashmolean lost a Persian carpet in a theft. They eventually got it back from a dry cleaners in New York."In January 2014, the Ashmolean made up for the painting's absence by becoming the first European museum to host an exhibit of Impressionist works from the Henry and Rose Pearlman Collection at the Princeton University Art Museum. Of the fifty paintings in Cézanne and the Modern, twenty-four were by the title artist, spanning his whole career. Museum staff recalled the theft as a low point in the museum's recent history that made them more elated to host the Pearlman exhibit. Investigation The Thames Valley Police assigned six officers to investigate. They knew their own resources would not be enough. "This is not a crime which is going to be solved overnight." said a spokesman. "We are more used to run-of-the-mill crimes. We need expertise." Accordingly they had called in specialists in art theft; customs officers at airports and harbours had been alerted in case anyone tried to take the painting out of Britain, although police believed that it was more likely in the possession of some domestic collector.At first police withheld some details of the crime in case a ransom request came in. Later in January they believed they were on the verge of recovering it after receiving a tip that it had been seen in a West Midlands pub. When they went there to investigate, it turned out to be a copy, its paint still wet, being painted by the landlord.As of 2021, no other leads have come in that police have discussed publicly; the investigation continues. In 2005 the U.S. Federal Bureau of Investigation (FBI) named the theft one the world's top ten art crimes; its Art Crime Team actively seeks information from the public that may lead to the recover of View of Auvers-sur-Oise. See also 1880 in art List of paintings by Paul Cézanne List of stolen paintings The Boy in the Red Vest, another Cézanne painting stolen (but later recovered) Notes == References ==	width	{ "answer_start": [ 1774 ], "text": [ "55" ] }
Sonam Bisht is an Indian beauty pageant and reality show contestant turned television actress. She hails from Dehradun and studied at Kendriya Vidyalaya Hathibarkala. In 2013 she was the first runner-up in the Miss Uttarakhand contest. She took part in the 2014 Miss India contest.That same year, she was also a contestant in the third season of reality show India's Best Cinestars Ki Khoj.In 2015, she landed a role in Zee TV's show Lajwanti. She is currently seen in Star Plus's soap opera Suhani Si Ek Ladki where she plays the negative lead, Yuvraj's second wife. Television == References ==	place of birth	{ "answer_start": [ 110 ], "text": [ "Dehradun" ] }
Sonam Bisht is an Indian beauty pageant and reality show contestant turned television actress. She hails from Dehradun and studied at Kendriya Vidyalaya Hathibarkala. In 2013 she was the first runner-up in the Miss Uttarakhand contest. She took part in the 2014 Miss India contest.That same year, she was also a contestant in the third season of reality show India's Best Cinestars Ki Khoj.In 2015, she landed a role in Zee TV's show Lajwanti. She is currently seen in Star Plus's soap opera Suhani Si Ek Ladki where she plays the negative lead, Yuvraj's second wife. Television == References ==	educated at	{ "answer_start": [ 134 ], "text": [ "Kendriya Vidyalaya" ] }
Operation Goodwood was a British offensive during the Second World War, which took place between 18 and 20 July 1944 as part of the larger battle for Caen in Normandy, France. The objective of the operation was a limited attack to the south, from the Orne bridgehead, to capture the rest of Caen and the Bourguébus Ridge beyond. At least one historian has called the operation the largest tank battle that the British Army has ever fought.Goodwood was preceded by Operations Greenline and Pomegranate in the Second Battle of the Odon west of Caen, to divert German attention from the area east of Caen. Goodwood began when the British VIII Corps, with three armoured divisions, attacked to seize the German-held Bourguébus Ridge, the area between Bretteville-sur-Laize and Vimont and to inflict maximum casualties on the Germans. On 18 July, the British I Corps conducted an attack to secure a series of villages to the east of VIII Corps; to the west, the II Canadian Corps launched Operation Atlantic, synchronised with Goodwood, to capture the Caen suburbs south of the Orne River. When the operation ended on 20 July, the armoured divisions had broken through the outer German defences and advanced 7 mi (11 km) but had been stopped short of Bourguébus Ridge, only armoured cars having penetrated further south and beyond the ridge. While Goodwood failed in its primary aim, it forced the Germans to keep powerful formations opposite the British and Canadians on the eastern flank of the Normandy beachhead and Operation Cobra, the First US Army attack which began on 25 July, caused the weaker German defences opposite to collapse. Background Caen The historic Normandy town of Caen was a D-Day objective for the British 3rd Infantry Division, which landed on Sword Beach on 6 June 1944. The capture of Caen, while "ambitious", was called the most important D-Day objective assigned to I Corps (Lieutenant-General John Crocker). Operation Overlord called for Second Army to secure the city and then form a front line from Caumont-l'Éventé–south-east of Caen, to acquire space for airfields and to protect the left flank of the First US Army (Lieutenant General Omar N. Bradley), while it moved on Cherbourg. Possession of Caen and its surroundings would give the Second Army a staging area for a push south to capture Falaise, which could be used as the pivot for a swing left, to advance on Argentan and then towards the Touques River. The terrain between Caen and Vimont was especially promising, being open, dry and conducive to mobile operations. Since the Allied forces greatly outnumbered the Germans in tanks and mobile units, a fluid fast-moving battle was to their advantage.Hampered by congestion in the beachhead and forced to divert effort to attack strongly held German positions along the 9.3 mi (15.0 km) route to the town, the 3rd Infantry Division was unable to assault Caen in force and was stopped short of the outskirts. Follow-up attacks were unsuccessful as German resistance solidified; abandoning the direct approach, Operation Perch—a pincer attack by I Corps and XXX Corps—was launched on 7 June, to encircle Caen from the east and west. I Corps, striking south out of the Orne bridgehead, was halted by the 21st Panzer Division and the attack by XXX Corps bogged down in front of Tilly-sur-Seulles, west of Caen, against the Panzer Lehr Division. The 7th Armoured Division pushed through a gap in the German front line and tried to capture the town of Villers-Bocage in the German rear. The Battle of Villers-Bocage saw the vanguard of the 7th Armoured Division withdraw from the town but by 17 June, Panzer Lehr had been forced back and XXX Corps had taken Tilly-sur-Seulles. The British postponed plans for further offensive operations, including a second attack by the 7th Armoured Division, when a severe storm descended upon the English Channel on 19 June. The storm lasted for three days, significantly delayed the Allied build-up. Most of the landing craft and ships already at sea were driven back to ports in Britain; towed barges and other loads (including 2.5 mi (4.0 km) of floating roadways for the Mulberry harbours) were lost and 800 craft were stranded on the Normandy beaches, until the next high tides in July. Epsom, Windsor and Charnwood After a few days to recover from the storm, the British began Operation Epsom on 26 June. The newly arrived VIII Corps (Lieutenant-General Richard O'Connor), was to attack west of Caen, southwards across the Odon and Orne rivers, capture an area of high ground near Bretteville-sur-Laize, encircling the city. The attack was preceded by Operation Martlet, to secure the VIII Corps flank by capturing high ground on the right of the axis of advance. The Germans managed to contain the offensive by committing all their strength, including two panzer divisions just arrived in Normandy, earmarked for an offensive against British and American positions around Bayeux. Several days later, the Second Army made a frontal assault on Caen Operation Charnwood. The attack was preceded by Operation Windsor, to capture the airfield at Carpiquet just outside Caen. By 9 July, Caen north of the Orne and Odon rivers had been captured but German forces retained possession of the south bank and a number of important locations, including the Colombelles steel works, whose tall chimneys commanded the area. Shortly after the capture of northern Caen during Operation Charnwood, the British mounted a raid against the Colombelles steelworks complex to the north-east of the city, which was a failure. The factory area remained in German hands, its tall chimneys providing observation posts that overlooked the Orne bridgehead. At 01:00 on 11 July, elements of the 153rd (Highland) Infantry Brigade, supported by Sherman tanks of the 148th Regiment Royal Armoured Corps, moved against the German position. The intention was to secure the area for troops from the Royal Engineers to destroy the chimneys before retiring. At 05:00, the British force was ambushed by Tiger tanks and was forced to withdraw after losing nine tanks. The Second Army launched two preliminary operations; according to Montgomery, their purpose was to "engage the enemy in battle unceasingly; we must 'write off' his troops; and generally we must kill Germans". Historian Terry Copp called this the moment where the Normandy campaign became a battle of attrition. Montgomery On 10 July, General Bernard Montgomery, the commander of all the Allied ground forces in Normandy, held a meeting at his headquarters with Dempsey and Bradley. They discussed 21st Army Group operations, following the conclusion of Operation Charnwood and the failure of the First US Army break-out offensive. Montgomery approved Operation Cobra, an attack to be launched by the First US Army on 18 July. Montgomery ordered Dempsey to "go on hitting: drawing the German strength, especially the armour, onto yourself—so as to ease the way for Brad".In early July, Montgomery had been informed by the Adjutant-General to the Forces, Ronald Adam that due to the manpower shortage in Britain, the pool of replacements to maintain his infantry strength was nearly exhausted. Dempsey proposed an attack consisting solely of armoured divisions, a concept that contradicted Montgomery's policy of never employing an unbalanced force. By mid-July, the Second Army had 2,250 medium tanks and 400 light tanks in the bridgehead, of which 500 were in reserve to replace losses. The armoured element of the Second Army consisted of the Guards Armoured Division, 7th Armoured Division and the 11th Armoured Division and the 4th Armoured Brigade, 8th Armoured Brigade, 27th Armoured Brigade and 33rd Armoured brigades, the 31st and 34th Tank brigades and the 2nd Canadian Armoured Brigade.At 10:00 on 13 July, Dempsey met with Crocker, Lieutenant-General Simonds of II Canadian Corps and O'Connor. Later that day, the first written order for Operation Goodwood—named after the Glorious Goodwood race meetings—was issued. The document contained only preliminary instructions and general intentions; it was to stimulate detailed planning and alterations were expected. The order was also sent to senior planners in the United Kingdom so that air support for the operation could be secured. When VIII Corps had assembled in Normandy in mid-June, it was suggested that the corps be used to attack out of the Orne bridgehead, to outflank Caen from the east but Operation Dreadnought was cancelled when Dempsey and O'Connor doubted the feasibility of the operation. Prelude Goodwood plan In the outline for Goodwood, VIII Corps, with three armoured divisions, would attack southwards out of the Orne bridgehead, a pocket of ground east of the river taken by the Allies on D-Day. The 11th Armoured Division was to advance south-west over Bourguébus Ridge and the Caen–Falaise road, aiming for Bretteville-sur-Laize. The Guards Armoured Division was to push south-east to capture Vimont and Argences and the 7th Armoured Division, starting last, was to aim south for Falaise. The 3rd Infantry Division, supported by part of the 51st (Highland) Infantry Division, was to secure the eastern flank by capturing the area around Émiéville, Touffréville and Troarn. The II Canadian Corps would simultaneously launch Operation Atlantic a supporting attack on the VIII Corps western flank, to capture Caen south of the Orne river. The British and Canadian operations were tentatively scheduled for 18 July and Cobra was postponed for two days, to enable the First Army to secure its start line around Saint-Lô.Detailed planning began on Friday 14 July but the next day, Montgomery issued a written directive ordering Dempsey to change the plan from a "deep break-out" to a "limited attack". Anticipating that the Germans would be forced to commit their armoured reserves, rather than risk a massed British tank breakthrough, VIII Corps was instructed to "engage the German armour in battle and 'write it down' to such an extent that it is of no further value to the Germans". He was to take any opportunity to improve the Second Army's position—the orders stated that "a victory on the eastern flank will help us to gain what we want on the western flank"—but not to endanger its role as a "firm bastion" on which the success of the forthcoming American offensive would depend. The objectives of the three armoured divisions were amended to "dominate the area Bourguébus–Vimont–Bretteville", although it was intended that "armoured cars should push far to the south towards Falaise, spread[ing] alarm and despondency". The objectives for the II Canadian Corps remained unchanged and it was stressed that these were vital, only following their achievement would VIII Corps "'crack about' as the situation demands".The 11th Armoured Division was to lead the advance, screen Cagny and capture Bras, Hubert-Folie, Verrières and Fontenay-le-Marmion. Its armoured brigade was to bypass most of the German-held villages in its area, leaving them to be dealt with by follow-up waves. The 159th Infantry Brigade, was initially to act independently of the rest of the division and capture Cuverville and Démouville. The Guards Armoured Division, advancing behind the 11th Armoured Division, was to capture Cagny and Vimont. Starting last, the 7th Armoured Division was to move south beyond the Garcelles-Secqueville ridge. Further advances by the armoured divisions were to be conducted only on Dempsey's order. The detailed orders for the II Canadian Corps were issued a day later, to capture Colombelles, the remaining portion of Caen and then be ready to move on the strongly held Verrières (Bourguébus) Ridge. If the German front collapsed, a deeper advance would be considered.Second Army intelligence had formed a good estimate of the opposition Goodwood was likely to face, although the German positions beyond the first line of villages had to be inferred, mainly from inconclusive air reconnaissance. The German defensive line was believed to consist of two belts up to 4 mi (6.4 km) deep. Aware that the Germans were expecting a large attack out of the Orne bridgehead, the British anticipated meeting resistance from the 16th Luftwaffe Field Division bolstered by SS-Panzergrenadier Regiment 25 of the 12th SS Panzer Division Hitlerjugend. Signals intelligence ascertained that the 12th SS Panzer Division had been moved into reserve and although it was slow to discover that SS-Panzergrenadier Regiment 25 was not with the 16th Luftwaffe Field Division, having also been placed into reserve, this oversight was rectified before 18 July. Battle groups of the 21st Panzer Division with around 50 Panzer IV and 34 assault guns, were expected near Route nationale 13. The 1st SS Division Leibstandarte SS Adolf Hitler was identified in reserve with an estimated 40 Panther tanks and 60 Panzer IV and the presence of two heavy tank battalions equipped with Tiger tanks was established. German armoured strength was estimated at 230 tanks and artillery strength at 300 field and anti-tank guns. The Second Army believed that 90 guns were in the centre of the battle zone, 40 on the flanks and 20 defending the Caen–Vimont railway line. The British had also located a German gun line on the Bourguébus Ridge but its strength and gun positions were unknown. To mask the operational objectives, the Second Army initiated a deception plan that included diversionary attacks launched by XII and XXX Corps. The three armoured divisions moved to their staging positions west of the Orne only at night and in radio silence; artillery fire was used to mask the noise of the tank engines. During the hours of daylight all efforts were made to camouflage the new positions.For artillery support, Goodwood was allocated 760 guns,with 297,600 rounds of ammunition. 456 field pieces from 19 field regiments, 208 medium guns from 13 medium regiments, 48 heavy pieces from 3 heavy regiments and 48 heavy anti-aircraft guns from two heavy anti-aircraft regiments. The artillery was provided by I, VIII, XII Corps and II Canadian Corps as well as the 2nd Canadian Army Group Royal Artillery (AGRA) and the 4th AGRA. Each field gun was allocated 500 rounds, each medium piece 300 rounds and each heavy gun or howitzer 150 rounds. Prior to the assault these were to attempt to suppress German anti-tank and field artillery positions. During the attack they would provide the 11th Armoured Division with a rolling barrage and anti-aircraft defence. The guns would also assist the attacks launched by the 3rd Infantry and 2nd Canadian Infantry divisions and fire on targets as requested. Additional support would be provided by three ships of the Royal Navy, whose targets were German gun batteries located near the coast in the region of Cabourg and Franceville. The engineering resources of the Second Army, I and VIII corps and the divisional engineers worked from 13–16 July to build six roads from west of the Orne River to the start lines east of the river and the Caen Canal. Engineers from I Corps strengthened bridges and built two new sets of bridges across the Orne and the canal. The engineers were also to construct another two sets of bridges by the end of the first day. II Canadian Corps planned to construct up to three bridges across the Orne as quickly as possible to give I and VIII corps exclusive access to the river and the canal bridges north of Caen. Engineers from the 51st (Highland) Infantry Division, with a small detachment from the 3rd Infantry Division, were ordered to breach the German minefield in front of the Highland Division. This was largely accomplished during the night of 16/17 July, when they cleared and marked fourteen gaps. By the morning of 18 July, 19 40 ft (12 m)-wide gaps had been completed, each for one armoured regiment to pass through at a time.The 11th Armoured Division infantry brigade, with the divisional and 29th Armoured Brigade headquarters, crossed into the Orne bridgehead during the night of 16/17 July and the rest of the division followed the next night. The Guards and 7th Armoured divisions were held west of the river until the operation began. As the final elements of the 11th Armoured Division moved into position and the VIII Corps headquarters took up residence in Bény-sur-Mer, more gaps in the minefields were blown, the forward areas were signposted and routes to be taken marked with white tape. Allied air forces Augmenting the preliminary artillery bombardment, 2,077 heavy and medium bombers of the Royal Air Force (RAF) and United States Army Air Forces (USAAF) would attack in three waves, in the largest air raid launched in direct support of ground forces in the campaign so far. Speed was an essential part of the Goodwood plan and it was hoped that the aerial bombardment would pave the way for the 11th Armoured Division, rapidly to secure the Bourguébus Ridge. Dempsey believed that if the operation were to succeed, his tanks would need to be on the ridge by the first afternoon and cancelled a second attack by heavy bombers scheduled for the first afternoon; although this was to be in direct support of the advance towards the ridge, he was concerned that the 11th Armoured Division should not be delayed waiting for the strike. Close air support for Goodwood would be provided by No. 83 Group RAF, to neutralise German positions on the flanks of VIII Corps, strong points such as the village of Cagny, attacking German gun and reserve positions and the interdiction of German troop movements. Each of the VIII Corps brigade headquarters, was allocated a Forward Air Control Post. German preparations The Germans considered the Caen area to be the foundation of their position in Normandy and were determined to maintain a defensive arc from the English Channel to the west bank of the Orne. On 15 July, German military intelligence warned Panzer Group West that from 17 July, a British attack out of the Orne bridgehead was likely. It was thought that the British would push south-east towards Paris. General Heinrich Eberbach, the commanding officer of Panzer Group West, designed a defensive plan, with its details worked out by his two corps and six divisional commanders. A belt of at least 10 miles (16 km) depth was constructed, organised into four defence lines. Villages within the belt were fortified and anti-tank guns placed along its southern and eastern edges. To allow tanks to move freely within the belt, the Germans decided not to establish anti-tank minefields between each defensive line. On 16 July, several reconnaissance flights were mounted over the British front but most of these were driven off by anti-aircraft fire. As dark fell, camera-equipped aircraft managed to bring back photographs taken by the light of flares, which revealed a one-way flow of traffic over the Orne into the British bridgehead. Later that day, a British Spitfire was shot down over German lines while photographing defences; British artillery and fighters attempted to destroy the crashed aircraft without success. LXXXVI Corps, reinforced by much artillery, held the front line. The 346th Infantry Division was dug in from the coast to the north of Touffreville and the depleted 16th Luftwaffe Field Division held the next section from Touffreville to Colombelles. Kampfgruppe von Luck, a battle group formed around the 21st Panzer Division 125th Panzergrenadier Regiment, was placed behind these forces with around 30 assault guns. The 21st Panzer Division armoured elements, reinforced with the 503rd Heavy Panzer Battalion, which included ten King Tigers, were north-east of Cagny in a position to support Luck's men and to act as a general reserve and the rest of the divisional panzergrenadiers, with towed anti-tank guns and assault guns, were dug in amongst the villages of the Caen plain. The 21st Panzer Division reconnaissance and pioneer battalions, were positioned on the Bourguébus Ridge to protect the corps artillery, which consisted of around 48 field and medium guns with an equal number of Nebelwerfer rocket launchers. The LXXXVI Corps had 194 artillery pieces, 272 Nebelwerfers and 78 anti-aircraft and anti-tank 88 mm guns. One battery of four 88 mm anti-aircraft guns from the 2nd Flak-Sturm Regiment, was positioned in Cagny, while in the villages along the Bourguébus Ridge there was a screen of 44 x 88 mm anti-tank guns from the 200th Tank Destroyer Battalion. Most of the LXXXVI Corps artillery was beyond the ridge covering the Caen–Falaise road.Facing Caen to the west of the Caen–Falaise road was the I SS Panzer Corps. On 14 July, elements of the 272nd Infantry Division took over the defence of Vaucelles from the 1st SS Division Leibstandarte SS Adolf Hitler, who moved into local reserve between the village of Ifs and the east bank of the Orne. The following day the 12th SS Panzer Division was placed in Oberkommando der Wehrmacht (OKW) reserve to rest and refit and—on Hitler's orders—to be in a position to meet a feared second Allied landing between the Orne and Seine rivers. The divisional artillery regiment and anti-aircraft battalion remained behind to support the 272nd Infantry Division and two battle groups were detached from the division. Kampfgruppe Waldmüller was moved close to Falaise and Kampfgruppe Wünsche to Lisieux, 40 kilometres (25 mi) east of Caen. Although Kampfgruppe Waldmüller was later ordered to rejoin the rest of the division at Lisieux, on 17 July Eberbach halted this move. Preliminary operations Operation Greenline Operation Greenline was launched by XII Corps during the evening of 15 July, with the 15th (Scottish) Infantry Division reinforced by a brigade of 53rd (Welsh) Infantry Division, the 34th Tank Brigade, 43rd (Wessex) Infantry Division and the 53rd (Welsh) Infantry Division, minus one brigade. Greenline was intended to convince the German command that the main British assault would be launched west of the Orne, through the positions held by XII Corps and to tie down the 9th and 10th SS Panzer divisions, so that they could not oppose Goodwood or Cobra. Supported by 450 guns, the British attack made use of artificial moonlight and started well despite disruption caused by German artillery fire. By dawn XII Corps had captured several of its objectives including the important height of Hill 113, although the much-contested Hill 112 remained in German hands. By committing the 9th SS Panzer Division, the Germans managed by the end of the day to largely restore their line, although a counter-attack against Hill 113 failed. Attacks next day by XII Corps gained no further ground and during the evening of 17 July, the operation was closed down and the British force on Hill 113 withdrawn. Operation Pomegranate Operation Pomegranate began on 16 July, in which XXX Corps was to capture several important villages. On the first day British infantry seized a key objective and took 300 prisoners but the next day there was much inconclusive fighting on the outskirts of Noyers-Bocage and Elements of the 9th SS Panzer Division were committed to the village defence. Although the British took control of the railway station and an area of high ground outside the village, Noyers-Bocage itself remained in German hands.The preliminary operations cost Second Army 3,500 casualties for no significant territorial gains but Greenline and Pomegranate were strategically successful. Reacting to the threats in the Odon Valley, the Germans retained the 2nd Panzer and 10th SS Panzer divisions in the front line and recalled the 9th SS Panzer Division from Corps reserve. The Germans suffered around 2,000 casualties. Terry Copp wrote that the fighting was "one of the bloodiest encounters of the campaign". During the late afternoon of 17 July, a patrolling Spitfire spotted a German staff car on the road near the village of Sainte-Foy-de-Montgommery. The fighter made a strafing attack driving the car off the road. Among its occupants was Field Marshal Erwin Rommel, the commander of Army Group B, who was seriously wounded, leaving Army Group B temporarily leaderless. Battle 18 July Shortly before dawn on 18 July, the Highland infantry in the south of the Orne bridgehead, quietly retired 0.5 mi (0.80 km) from the front line. At 05:45, 1,056 Handley Page Halifax and Avro Lancaster heavy bombers flying at 3,000 ft (910 m) dropped 4,800 long tons (4,900 t) of high explosive bombs around Colombelles, the steelworks, on the positions of the 21st Panzer Division and on the village of Cagny, reducing half of it to rubble. At 06:40 the British artillery opened fire and twenty minutes later, the second wave of bombers arrived. From 10,000–13,000 ft (3,000–4,000 m), American B-26 Marauders released 563 long tons (572 t) of fragmentation bombs on the 16th Luftwaffe Field Division, as fighter-bombers attacked German strong points and gun positions. During the 45-minute bombardment, the troops and tanks of the 11th Armoured Division moved out of their concentration areas towards the start line. H Hour was set for 07:45 and on schedule, the artillery switched to a creeping barrage, which moved ahead of the 11th Armoured Division. As the division moved off, more artillery opened fire on Cuverville, Demouville, Giberville, Liberville, Cagny and Émiéville and dropped harassing fire on targets as far south as Garcelles-Secqueville and Secqueville la Campagne. Fifteen minutes later, American heavy bombers dropped 1,340 long tons (1,360 t) of fragmentation bombs in the Troarn area and on the main German gun line on the Bourguébus Ridge. Only 25 bombers in the three waves were lost, all to German anti aircraft fire. Aerial support for the operation was then handed over to 800 fighter-bombers of 83 and 84 Groups.The bombing put the 22nd Panzer Regiment and the III Company, 503rd Heavy Panzer Battalion temporarily out of action, causing varying degrees of damage to their tanks. Some were overturned, some were destroyed and twenty were later found abandoned in bomb craters. Most of the German front line positions had been neutralised, with the survivors left "dazed and incoherent". Dust and smoke had impaired the ability of the bomber crews to identify all their targets and others on the periphery of the bombing zones had remained untouched. Cagny and Émiéville were extensively bombed but most of the defenders were unscathed and recovered in time to meet the British advance—both places having clear lines of fire, on the route the British were to take. The 503rd Heavy Tank Battalion rallied rapidly and got to work digging out their tanks. On the Bourguébus Ridge, a number of guns were destroyed by the bombing but most of the artillery and anti-tank guns remained intact. By 08:05, the 2nd Fife and Forfar Yeomanry and the 3rd Royal Tank Regiment of the 29th Armoured Brigade, had navigated minefields, to reach the Caen–Troarn railway line. The first phase of the rolling barrage ended at 08:30, by which time large numbers of prisoners from the 16th Luftwaffe Division had been rounded up. By the time the artillery resumed firing at 08:50, only the first armoured regiment and a portion of the second had crossed the line. Although opposition was still minimal and more prisoners were taken, the two regiments struggled to keep up with the barrage and were moving out of supporting range of their reserves. On schedule at 09:00 the barrage lifted and 35 minutes later, the lead squadrons reached the Caen–Vimont railway. In reserve, the 23rd Hussars had managed to clear the first railway line only to become embroiled in a 1+1⁄2-hour engagement with a battery of self-propelled guns of the 200th Assault Gun Battalion, that had been mistaken for Tiger tanks. As the 2nd Fife and Forfar Yeomanry advanced past Cagny, they were engaged by anti-tank guns in Cagny to the east. Within a few minutes at least twelve tanks were disabled. The Yeomanry pressed their advance south and were engaged by the main German gun line on the ridge, while the 3rd Royal Tank Regiment having shifted westward and exchanged fire with the German garrison in Grentheville, before moving around the village and advancing along the southern outskirts of Caen, towards Bras and Hubert-Folie. What had been conceived as an attack towards the Bourguébus Ridge by three armoured divisions, had become an unsupported advance by two tank regiments, out of sight of one other, against heavy German fire. By 11:15, the British reached the ridge and the villages of Bras and Bourguébus. Some losses were inflicted on the German tanks but attempts to advance further were met by determined opposition, including fire from the rear from pockets of resistance that had been bypassed.General Eberbach ordered a counter-attack, "not a defensive move but a full armoured charge". The 1st SS Panzer Division was to attack across the ridge, while in the Cagny area the 21st Panzer Division was to recover all lost ground. German tanks started to arrive on the ridge around noon and the British tank crews were soon reporting German tanks and guns everywhere. Hawker Typhoon fighter-bombers carrying RP-3 rockets were directed onto the ridge throughout the afternoon, delaying and eventually breaking up the 1st SS Panzer Division counter-attack. A final attempt to storm the ridge resulted in the loss of 16 British tanks and a small counter-attack during the afternoon was driven off, with the destruction of six German Panthers.Just before 10:00, the Guards Armoured Division caught up with the 11th Armoured Division and pressed on towards Cagny. By 12:00 the leading elements were halted, engaged in fighting. A German counter-attack against the 2nd Armoured Grenadier Guards by 19 tanks from the 21st Panzer Division and the Tigers of the 503rd Heavy Panzer Battalion, failed when the German tanks came under fire from their own guns and two Tigers were knocked out. An isolated Tiger II (King Tiger) attempting to manoeuvre out of danger, was caught by an Irish Guards Sherman tank that had also become detached from its unit. The Sherman crew fired into the Tiger and then rammed it; anti-tank fire from other British units then penetrated the Tiger's armour. Both crews abandoned their vehicles and most of the German crew was captured. The 503rd Heavy Panzer Battalion later attacked the Coldstream Guards but was forced to withdraw by massed anti-tank fire. It took the Guards the rest of the day to capture Cagny, which was found abandoned when infantry entered the village. Attempts to renew the advance were met by fierce German resistance. Starting last, the only element of the 7th Armoured Division to enter the battle was the 5th Royal Tank Regiment (5th RTR). At 17:00 near Cuverville it knocked out two Panzer IVs for the loss of four tanks and then cleared Grentheville which had been bypassed earlier in the day by the 3rd RTR and several prisoners were taken. A German counter-attack by six tanks petered out after two tanks each were destroyed. The 11th Armoured Division pulled back to the Caen–Vimont railway line for the evening and replacement tanks were brought forward for all divisions, with the 11th Armoured receiving priority. German recovery teams went forward to recover and repair as many of their tanks as possible, as few replacements were available. Unnoticed by the British, a gap had been created between Emièville and Troan. This was closed during the night by the 12th SS Panzer Division, which had lost ten tanks, en route, to air attacks. A number of minor German counter-attacks were launched from the ridge; one at dusk was broken up by British artillery and anti-tank fire, which destroyed a Panther and Tiger, another after dark led by a captured Sherman as a ruse, was repulsed after the Sherman and two Panthers were knocked out by a British anti-tank battery. During the night, German bombers dropped flares over the Orne bridges, which then came under aerial attack. One bridge was slightly damaged and the headquarters of the 11th Armoured Division was hit, as were some tank crews who had survived the fighting.In their fighting around Cagny, the Guards Armoured Division lost fifteen tanks destroyed and 45 tanks damaged. The 11th Armoured Division lost 126 tanks, although only forty were write-offs; the rest were damaged or had broken down. (The loss of 126 tanks of the 219–244 tanks that crossed the start line has been a common feature of accounts of Goodwood but the divisional commander, the VIII Corps historian and Chester Wilmot gave 126 tank losses. Michael Reynolds gave "...at least 125" and Christopher Dunphie 128 losses.) The armoured divisions suffered 521 casualties during the day, Guards Armoured Division suffered 127 casualties, the 7th Armoured Division had 48 casualties and the 11th Armoured Division had 336 casualties. On the eastern flank, the 3rd Infantry Division had a successful day, capturing all of its objectives except for Troarn. Operation Atlantic On the Canadian front, Operation Atlantic began at 08:15, with a rolling barrage and infantry and tanks crossed their start line twenty minutes later. At 08:40, British infantry from the 159th Infantry Brigade entered Cuverville; the village and its surrounding area were secured by 10:30 but patrols found Demouville firmly held and attempts to capture this second objective were delayed while the infantry reorganised. The rest of the day saw a slow southward advance, as numerous German positions were cleared. Linking up with their armoured support by nightfall, the infantry dug in around le Mesnil-Frèmentel. 19–20 July The German armour counter-attacked late in the afternoon and fighting continued along the high ground and around Hubert-Folie on 19 July and 20 July, bringing the attack to a halt. On 21 July, Dempsey started to secure his gains by substituting infantry for armour. Aftermath Analysis Tactically, the Germans contained the offensive, holding many of their main positions and preventing an Allied breakthrough, but they had been startled by the weight of the attack and preliminary aerial bombardment. It was clear that any defensive system less than 5 mi (8.0 km) deep could be overwhelmed at a stroke and the Germans could afford to man their defences in such depth only in the sector south of Caen. Goodwood resulted in the British extending the front line by 7 mi (11 km) to the east of Caen, with the penetration being as much as 12,000 yards (11 km; 6.8 mi) in some places; the southern suburbs of Caen were captured by the Canadians during Operation Atlantic.The attack reinforced the German view that the greatest danger was on the eastern flank. As German armoured reinforcements arrived in Normandy, they were drawn into defensive battles in the east and worn down. By the end of July only one and a half panzer divisions were facing American forces at the western end of the front, compared with six and a half facing the British and Canadians at the eastern end of the bridgehead. The German defence of Normandy was close to collapse when Operation Cobra breached the thin German defensive 'crust' in the west and few German mechanised units were available to counter-attack. Martin Blumenson, the American official historian, wrote after the war that had Goodwood created a breakthrough, "... Cobra would probably have been unnecessary". Goodwood inflicted substantial losses on the German defenders but not a shattering blow. The effect on the morale of the German commanders was greater and added to the loss of Rommel, who was wounded in an RAF air attack. Kluge lost his early optimism on being appointed to replace Rundstedt and wrote to Hitler on 21 July predicting an imminent collapse.Operation Goodwood was launched at a time of great frustration in the higher command of the Allies, which contributed to the controversy surrounding the operation. The Allied bridgehead was about 20 percent of the planned size, which led to congestion and some fear of a stalemate. Allied commanders had not been able to exploit their potentially decisive advantages in mobility during June and early July 1944. Much of the controversy surrounding the objectives of the battle originates from the conflicting messages given by Montgomery. He talked up the objectives of Goodwood to the press on the first day, later saying that this was propaganda to encourage the Germans to keep powerful units at the east end of the battlefield.In the planning of Goodwood, Montgomery appeared to promise that the attack would be a breakthrough and that when the VIII Corps failed to break-out, by some accounts the Supreme Commander, US General Dwight D. Eisenhower, felt he had been misled. While his intermittent communications to Supreme Headquarters Allied Expeditionary Force (SHAEF) appeared to promise a breakthrough, Montgomery was writing orders to his subordinates for a limited attack. Copies of orders forwarded to SHAEF called for an armoured division to take Falaise, a town far in the German rear. Three days prior to the attack, Montgomery revised the orders, eliminating Falaise as an objective but neglected to forward copies of the revision; Eisenhower was later furious at the result, which dogged Montgomery, as it allowed his detractors, especially Air Marshal Arthur Tedder, to imply that the operation was a failure.Stephen Biddle wrote that Goodwood was a significant tactical setback for Montgomery. Despite having preponderant force and air superiority, British progress was slow and ultimately failed to break through. Montgomery chose an unusually narrow spearhead of just 2 km (1.2 mi), which created a congested line of advance. British infantry was lacking in suitable junior officers and non-commissioned officers, which inhibited small-unit tactics. In Biddle's analysis, The British systematically failed to coordinate movement and suppressive fires after about mid-morning of the opening day.... The attack had by then moved beyond the reach of the British batteries on the northern side of the Orne River and the congestion in the march columns had kept the artillery from moving forward into supporting range.... The net result was thus an exposed, massed, nearly pure-tank assault pressing forward rapidly without supporting infantry or supporting suppressive fires. The Germans, by contrast, made great efforts to conceal their forces—moving under cover of dark, off the main roads, in small units and under radio silence. Casualties Simon Trew wrote that "the first estimates of Allied losses for Operation Goodwood appeared horrific, that Second Army had lost 4,011 men... ." In 2006, G. S. Jackson gave casualties in the armoured divisions from 18 to 19 July of 1,020 men. In 2001, Michael Reynolds quoted the 21st Army Group war diary of casualties in I and VIII Corps of 3,474 men. Operation Atlantic cost the Canadians from 1,349 to 1,965 casualties. Colonel Charles Stacey, the Canadian official historian, gave casualties of all Canadian units in Europe, for the four days' fighting of 1,965 in all categories; 441 men were killed or died of wounds. Simon Trew wrote that "no conclusive assessment can ever be made" in regards to the losses of both sides. In 2014, John Buckley gave a figure of 5,500 casualties during Goodwood and Atlantic.Over 2,000 German prisoners were taken and c. 100 tanks were destroyed. Jackson also wrote of c. 100 German tank losses. In the official history Major Lionel Ellis wrote that the 1st SS and 21st Panzer divisions lost 109 tanks on the first day of the battle. Reynolds recorded 77 German tanks or assault guns knocked out or damaged during the operation and that the claim of 75 tanks or assault guns destroyed—as stated in a post-war interview, by the commanding officer of the 11th Armoured Division, for a British staff college training film on the operation—"can be accepted as accurate". Michael Tamelander wrote in 2004 that Panzergruppe West recorded the loss of 75 tanks during the period from 16 to 21 July.British tank losses during Goodwood have been debated, with the loss ranging from 218 to 500. In addition to VIII Corps losses, about twenty tanks were lost in the flanking operations. Reynolds wrote that study of the records suggests that the maximum number of tanks lost during Operation Goodwood was 253, most of which were damaged rather than write-offs. Tamelander and Niklas Zetterling wrote that during Goodwood 469 tanks were lost by the armoured divisions (including 131 tanks on 19 July and 68 on 20 July) but that the majority could be repaired. Trew rejected those figures and wrote that after much investigation, VIII Corps losses amounted to 197 tanks on 18 July, 99 tanks on 19 July and 18 tanks on 20 July, "for a total of 314, of which 130 were completely destroyed". Trew wrote that "the tank strength returns for VIII Corps 18–21 July show a loss of 218 tanks (that could not be repaired or immediately replaced), including 145 tanks from 11th Armoured Division". In 2014 John Buckley wrote that 400 British tanks were knocked out and that many were recovered and put back into service, although the morale of some of the crews deteriorated. Notes Footnotes References Further reading External links Morss, R. "59th (Staffordshire) Division in WWII: Operation Pomegranate". Retrieved 18 May 2014. Zetterling: data on German losses in Normandy RAF photograph of Sannerville and Banneville la Campagne after the morning raid of 18 July 1944	country	{ "answer_start": [ 168 ], "text": [ "France" ] }
Operation Goodwood was a British offensive during the Second World War, which took place between 18 and 20 July 1944 as part of the larger battle for Caen in Normandy, France. The objective of the operation was a limited attack to the south, from the Orne bridgehead, to capture the rest of Caen and the Bourguébus Ridge beyond. At least one historian has called the operation the largest tank battle that the British Army has ever fought.Goodwood was preceded by Operations Greenline and Pomegranate in the Second Battle of the Odon west of Caen, to divert German attention from the area east of Caen. Goodwood began when the British VIII Corps, with three armoured divisions, attacked to seize the German-held Bourguébus Ridge, the area between Bretteville-sur-Laize and Vimont and to inflict maximum casualties on the Germans. On 18 July, the British I Corps conducted an attack to secure a series of villages to the east of VIII Corps; to the west, the II Canadian Corps launched Operation Atlantic, synchronised with Goodwood, to capture the Caen suburbs south of the Orne River. When the operation ended on 20 July, the armoured divisions had broken through the outer German defences and advanced 7 mi (11 km) but had been stopped short of Bourguébus Ridge, only armoured cars having penetrated further south and beyond the ridge. While Goodwood failed in its primary aim, it forced the Germans to keep powerful formations opposite the British and Canadians on the eastern flank of the Normandy beachhead and Operation Cobra, the First US Army attack which began on 25 July, caused the weaker German defences opposite to collapse. Background Caen The historic Normandy town of Caen was a D-Day objective for the British 3rd Infantry Division, which landed on Sword Beach on 6 June 1944. The capture of Caen, while "ambitious", was called the most important D-Day objective assigned to I Corps (Lieutenant-General John Crocker). Operation Overlord called for Second Army to secure the city and then form a front line from Caumont-l'Éventé–south-east of Caen, to acquire space for airfields and to protect the left flank of the First US Army (Lieutenant General Omar N. Bradley), while it moved on Cherbourg. Possession of Caen and its surroundings would give the Second Army a staging area for a push south to capture Falaise, which could be used as the pivot for a swing left, to advance on Argentan and then towards the Touques River. The terrain between Caen and Vimont was especially promising, being open, dry and conducive to mobile operations. Since the Allied forces greatly outnumbered the Germans in tanks and mobile units, a fluid fast-moving battle was to their advantage.Hampered by congestion in the beachhead and forced to divert effort to attack strongly held German positions along the 9.3 mi (15.0 km) route to the town, the 3rd Infantry Division was unable to assault Caen in force and was stopped short of the outskirts. Follow-up attacks were unsuccessful as German resistance solidified; abandoning the direct approach, Operation Perch—a pincer attack by I Corps and XXX Corps—was launched on 7 June, to encircle Caen from the east and west. I Corps, striking south out of the Orne bridgehead, was halted by the 21st Panzer Division and the attack by XXX Corps bogged down in front of Tilly-sur-Seulles, west of Caen, against the Panzer Lehr Division. The 7th Armoured Division pushed through a gap in the German front line and tried to capture the town of Villers-Bocage in the German rear. The Battle of Villers-Bocage saw the vanguard of the 7th Armoured Division withdraw from the town but by 17 June, Panzer Lehr had been forced back and XXX Corps had taken Tilly-sur-Seulles. The British postponed plans for further offensive operations, including a second attack by the 7th Armoured Division, when a severe storm descended upon the English Channel on 19 June. The storm lasted for three days, significantly delayed the Allied build-up. Most of the landing craft and ships already at sea were driven back to ports in Britain; towed barges and other loads (including 2.5 mi (4.0 km) of floating roadways for the Mulberry harbours) were lost and 800 craft were stranded on the Normandy beaches, until the next high tides in July. Epsom, Windsor and Charnwood After a few days to recover from the storm, the British began Operation Epsom on 26 June. The newly arrived VIII Corps (Lieutenant-General Richard O'Connor), was to attack west of Caen, southwards across the Odon and Orne rivers, capture an area of high ground near Bretteville-sur-Laize, encircling the city. The attack was preceded by Operation Martlet, to secure the VIII Corps flank by capturing high ground on the right of the axis of advance. The Germans managed to contain the offensive by committing all their strength, including two panzer divisions just arrived in Normandy, earmarked for an offensive against British and American positions around Bayeux. Several days later, the Second Army made a frontal assault on Caen Operation Charnwood. The attack was preceded by Operation Windsor, to capture the airfield at Carpiquet just outside Caen. By 9 July, Caen north of the Orne and Odon rivers had been captured but German forces retained possession of the south bank and a number of important locations, including the Colombelles steel works, whose tall chimneys commanded the area. Shortly after the capture of northern Caen during Operation Charnwood, the British mounted a raid against the Colombelles steelworks complex to the north-east of the city, which was a failure. The factory area remained in German hands, its tall chimneys providing observation posts that overlooked the Orne bridgehead. At 01:00 on 11 July, elements of the 153rd (Highland) Infantry Brigade, supported by Sherman tanks of the 148th Regiment Royal Armoured Corps, moved against the German position. The intention was to secure the area for troops from the Royal Engineers to destroy the chimneys before retiring. At 05:00, the British force was ambushed by Tiger tanks and was forced to withdraw after losing nine tanks. The Second Army launched two preliminary operations; according to Montgomery, their purpose was to "engage the enemy in battle unceasingly; we must 'write off' his troops; and generally we must kill Germans". Historian Terry Copp called this the moment where the Normandy campaign became a battle of attrition. Montgomery On 10 July, General Bernard Montgomery, the commander of all the Allied ground forces in Normandy, held a meeting at his headquarters with Dempsey and Bradley. They discussed 21st Army Group operations, following the conclusion of Operation Charnwood and the failure of the First US Army break-out offensive. Montgomery approved Operation Cobra, an attack to be launched by the First US Army on 18 July. Montgomery ordered Dempsey to "go on hitting: drawing the German strength, especially the armour, onto yourself—so as to ease the way for Brad".In early July, Montgomery had been informed by the Adjutant-General to the Forces, Ronald Adam that due to the manpower shortage in Britain, the pool of replacements to maintain his infantry strength was nearly exhausted. Dempsey proposed an attack consisting solely of armoured divisions, a concept that contradicted Montgomery's policy of never employing an unbalanced force. By mid-July, the Second Army had 2,250 medium tanks and 400 light tanks in the bridgehead, of which 500 were in reserve to replace losses. The armoured element of the Second Army consisted of the Guards Armoured Division, 7th Armoured Division and the 11th Armoured Division and the 4th Armoured Brigade, 8th Armoured Brigade, 27th Armoured Brigade and 33rd Armoured brigades, the 31st and 34th Tank brigades and the 2nd Canadian Armoured Brigade.At 10:00 on 13 July, Dempsey met with Crocker, Lieutenant-General Simonds of II Canadian Corps and O'Connor. Later that day, the first written order for Operation Goodwood—named after the Glorious Goodwood race meetings—was issued. The document contained only preliminary instructions and general intentions; it was to stimulate detailed planning and alterations were expected. The order was also sent to senior planners in the United Kingdom so that air support for the operation could be secured. When VIII Corps had assembled in Normandy in mid-June, it was suggested that the corps be used to attack out of the Orne bridgehead, to outflank Caen from the east but Operation Dreadnought was cancelled when Dempsey and O'Connor doubted the feasibility of the operation. Prelude Goodwood plan In the outline for Goodwood, VIII Corps, with three armoured divisions, would attack southwards out of the Orne bridgehead, a pocket of ground east of the river taken by the Allies on D-Day. The 11th Armoured Division was to advance south-west over Bourguébus Ridge and the Caen–Falaise road, aiming for Bretteville-sur-Laize. The Guards Armoured Division was to push south-east to capture Vimont and Argences and the 7th Armoured Division, starting last, was to aim south for Falaise. The 3rd Infantry Division, supported by part of the 51st (Highland) Infantry Division, was to secure the eastern flank by capturing the area around Émiéville, Touffréville and Troarn. The II Canadian Corps would simultaneously launch Operation Atlantic a supporting attack on the VIII Corps western flank, to capture Caen south of the Orne river. The British and Canadian operations were tentatively scheduled for 18 July and Cobra was postponed for two days, to enable the First Army to secure its start line around Saint-Lô.Detailed planning began on Friday 14 July but the next day, Montgomery issued a written directive ordering Dempsey to change the plan from a "deep break-out" to a "limited attack". Anticipating that the Germans would be forced to commit their armoured reserves, rather than risk a massed British tank breakthrough, VIII Corps was instructed to "engage the German armour in battle and 'write it down' to such an extent that it is of no further value to the Germans". He was to take any opportunity to improve the Second Army's position—the orders stated that "a victory on the eastern flank will help us to gain what we want on the western flank"—but not to endanger its role as a "firm bastion" on which the success of the forthcoming American offensive would depend. The objectives of the three armoured divisions were amended to "dominate the area Bourguébus–Vimont–Bretteville", although it was intended that "armoured cars should push far to the south towards Falaise, spread[ing] alarm and despondency". The objectives for the II Canadian Corps remained unchanged and it was stressed that these were vital, only following their achievement would VIII Corps "'crack about' as the situation demands".The 11th Armoured Division was to lead the advance, screen Cagny and capture Bras, Hubert-Folie, Verrières and Fontenay-le-Marmion. Its armoured brigade was to bypass most of the German-held villages in its area, leaving them to be dealt with by follow-up waves. The 159th Infantry Brigade, was initially to act independently of the rest of the division and capture Cuverville and Démouville. The Guards Armoured Division, advancing behind the 11th Armoured Division, was to capture Cagny and Vimont. Starting last, the 7th Armoured Division was to move south beyond the Garcelles-Secqueville ridge. Further advances by the armoured divisions were to be conducted only on Dempsey's order. The detailed orders for the II Canadian Corps were issued a day later, to capture Colombelles, the remaining portion of Caen and then be ready to move on the strongly held Verrières (Bourguébus) Ridge. If the German front collapsed, a deeper advance would be considered.Second Army intelligence had formed a good estimate of the opposition Goodwood was likely to face, although the German positions beyond the first line of villages had to be inferred, mainly from inconclusive air reconnaissance. The German defensive line was believed to consist of two belts up to 4 mi (6.4 km) deep. Aware that the Germans were expecting a large attack out of the Orne bridgehead, the British anticipated meeting resistance from the 16th Luftwaffe Field Division bolstered by SS-Panzergrenadier Regiment 25 of the 12th SS Panzer Division Hitlerjugend. Signals intelligence ascertained that the 12th SS Panzer Division had been moved into reserve and although it was slow to discover that SS-Panzergrenadier Regiment 25 was not with the 16th Luftwaffe Field Division, having also been placed into reserve, this oversight was rectified before 18 July. Battle groups of the 21st Panzer Division with around 50 Panzer IV and 34 assault guns, were expected near Route nationale 13. The 1st SS Division Leibstandarte SS Adolf Hitler was identified in reserve with an estimated 40 Panther tanks and 60 Panzer IV and the presence of two heavy tank battalions equipped with Tiger tanks was established. German armoured strength was estimated at 230 tanks and artillery strength at 300 field and anti-tank guns. The Second Army believed that 90 guns were in the centre of the battle zone, 40 on the flanks and 20 defending the Caen–Vimont railway line. The British had also located a German gun line on the Bourguébus Ridge but its strength and gun positions were unknown. To mask the operational objectives, the Second Army initiated a deception plan that included diversionary attacks launched by XII and XXX Corps. The three armoured divisions moved to their staging positions west of the Orne only at night and in radio silence; artillery fire was used to mask the noise of the tank engines. During the hours of daylight all efforts were made to camouflage the new positions.For artillery support, Goodwood was allocated 760 guns,with 297,600 rounds of ammunition. 456 field pieces from 19 field regiments, 208 medium guns from 13 medium regiments, 48 heavy pieces from 3 heavy regiments and 48 heavy anti-aircraft guns from two heavy anti-aircraft regiments. The artillery was provided by I, VIII, XII Corps and II Canadian Corps as well as the 2nd Canadian Army Group Royal Artillery (AGRA) and the 4th AGRA. Each field gun was allocated 500 rounds, each medium piece 300 rounds and each heavy gun or howitzer 150 rounds. Prior to the assault these were to attempt to suppress German anti-tank and field artillery positions. During the attack they would provide the 11th Armoured Division with a rolling barrage and anti-aircraft defence. The guns would also assist the attacks launched by the 3rd Infantry and 2nd Canadian Infantry divisions and fire on targets as requested. Additional support would be provided by three ships of the Royal Navy, whose targets were German gun batteries located near the coast in the region of Cabourg and Franceville. The engineering resources of the Second Army, I and VIII corps and the divisional engineers worked from 13–16 July to build six roads from west of the Orne River to the start lines east of the river and the Caen Canal. Engineers from I Corps strengthened bridges and built two new sets of bridges across the Orne and the canal. The engineers were also to construct another two sets of bridges by the end of the first day. II Canadian Corps planned to construct up to three bridges across the Orne as quickly as possible to give I and VIII corps exclusive access to the river and the canal bridges north of Caen. Engineers from the 51st (Highland) Infantry Division, with a small detachment from the 3rd Infantry Division, were ordered to breach the German minefield in front of the Highland Division. This was largely accomplished during the night of 16/17 July, when they cleared and marked fourteen gaps. By the morning of 18 July, 19 40 ft (12 m)-wide gaps had been completed, each for one armoured regiment to pass through at a time.The 11th Armoured Division infantry brigade, with the divisional and 29th Armoured Brigade headquarters, crossed into the Orne bridgehead during the night of 16/17 July and the rest of the division followed the next night. The Guards and 7th Armoured divisions were held west of the river until the operation began. As the final elements of the 11th Armoured Division moved into position and the VIII Corps headquarters took up residence in Bény-sur-Mer, more gaps in the minefields were blown, the forward areas were signposted and routes to be taken marked with white tape. Allied air forces Augmenting the preliminary artillery bombardment, 2,077 heavy and medium bombers of the Royal Air Force (RAF) and United States Army Air Forces (USAAF) would attack in three waves, in the largest air raid launched in direct support of ground forces in the campaign so far. Speed was an essential part of the Goodwood plan and it was hoped that the aerial bombardment would pave the way for the 11th Armoured Division, rapidly to secure the Bourguébus Ridge. Dempsey believed that if the operation were to succeed, his tanks would need to be on the ridge by the first afternoon and cancelled a second attack by heavy bombers scheduled for the first afternoon; although this was to be in direct support of the advance towards the ridge, he was concerned that the 11th Armoured Division should not be delayed waiting for the strike. Close air support for Goodwood would be provided by No. 83 Group RAF, to neutralise German positions on the flanks of VIII Corps, strong points such as the village of Cagny, attacking German gun and reserve positions and the interdiction of German troop movements. Each of the VIII Corps brigade headquarters, was allocated a Forward Air Control Post. German preparations The Germans considered the Caen area to be the foundation of their position in Normandy and were determined to maintain a defensive arc from the English Channel to the west bank of the Orne. On 15 July, German military intelligence warned Panzer Group West that from 17 July, a British attack out of the Orne bridgehead was likely. It was thought that the British would push south-east towards Paris. General Heinrich Eberbach, the commanding officer of Panzer Group West, designed a defensive plan, with its details worked out by his two corps and six divisional commanders. A belt of at least 10 miles (16 km) depth was constructed, organised into four defence lines. Villages within the belt were fortified and anti-tank guns placed along its southern and eastern edges. To allow tanks to move freely within the belt, the Germans decided not to establish anti-tank minefields between each defensive line. On 16 July, several reconnaissance flights were mounted over the British front but most of these were driven off by anti-aircraft fire. As dark fell, camera-equipped aircraft managed to bring back photographs taken by the light of flares, which revealed a one-way flow of traffic over the Orne into the British bridgehead. Later that day, a British Spitfire was shot down over German lines while photographing defences; British artillery and fighters attempted to destroy the crashed aircraft without success. LXXXVI Corps, reinforced by much artillery, held the front line. The 346th Infantry Division was dug in from the coast to the north of Touffreville and the depleted 16th Luftwaffe Field Division held the next section from Touffreville to Colombelles. Kampfgruppe von Luck, a battle group formed around the 21st Panzer Division 125th Panzergrenadier Regiment, was placed behind these forces with around 30 assault guns. The 21st Panzer Division armoured elements, reinforced with the 503rd Heavy Panzer Battalion, which included ten King Tigers, were north-east of Cagny in a position to support Luck's men and to act as a general reserve and the rest of the divisional panzergrenadiers, with towed anti-tank guns and assault guns, were dug in amongst the villages of the Caen plain. The 21st Panzer Division reconnaissance and pioneer battalions, were positioned on the Bourguébus Ridge to protect the corps artillery, which consisted of around 48 field and medium guns with an equal number of Nebelwerfer rocket launchers. The LXXXVI Corps had 194 artillery pieces, 272 Nebelwerfers and 78 anti-aircraft and anti-tank 88 mm guns. One battery of four 88 mm anti-aircraft guns from the 2nd Flak-Sturm Regiment, was positioned in Cagny, while in the villages along the Bourguébus Ridge there was a screen of 44 x 88 mm anti-tank guns from the 200th Tank Destroyer Battalion. Most of the LXXXVI Corps artillery was beyond the ridge covering the Caen–Falaise road.Facing Caen to the west of the Caen–Falaise road was the I SS Panzer Corps. On 14 July, elements of the 272nd Infantry Division took over the defence of Vaucelles from the 1st SS Division Leibstandarte SS Adolf Hitler, who moved into local reserve between the village of Ifs and the east bank of the Orne. The following day the 12th SS Panzer Division was placed in Oberkommando der Wehrmacht (OKW) reserve to rest and refit and—on Hitler's orders—to be in a position to meet a feared second Allied landing between the Orne and Seine rivers. The divisional artillery regiment and anti-aircraft battalion remained behind to support the 272nd Infantry Division and two battle groups were detached from the division. Kampfgruppe Waldmüller was moved close to Falaise and Kampfgruppe Wünsche to Lisieux, 40 kilometres (25 mi) east of Caen. Although Kampfgruppe Waldmüller was later ordered to rejoin the rest of the division at Lisieux, on 17 July Eberbach halted this move. Preliminary operations Operation Greenline Operation Greenline was launched by XII Corps during the evening of 15 July, with the 15th (Scottish) Infantry Division reinforced by a brigade of 53rd (Welsh) Infantry Division, the 34th Tank Brigade, 43rd (Wessex) Infantry Division and the 53rd (Welsh) Infantry Division, minus one brigade. Greenline was intended to convince the German command that the main British assault would be launched west of the Orne, through the positions held by XII Corps and to tie down the 9th and 10th SS Panzer divisions, so that they could not oppose Goodwood or Cobra. Supported by 450 guns, the British attack made use of artificial moonlight and started well despite disruption caused by German artillery fire. By dawn XII Corps had captured several of its objectives including the important height of Hill 113, although the much-contested Hill 112 remained in German hands. By committing the 9th SS Panzer Division, the Germans managed by the end of the day to largely restore their line, although a counter-attack against Hill 113 failed. Attacks next day by XII Corps gained no further ground and during the evening of 17 July, the operation was closed down and the British force on Hill 113 withdrawn. Operation Pomegranate Operation Pomegranate began on 16 July, in which XXX Corps was to capture several important villages. On the first day British infantry seized a key objective and took 300 prisoners but the next day there was much inconclusive fighting on the outskirts of Noyers-Bocage and Elements of the 9th SS Panzer Division were committed to the village defence. Although the British took control of the railway station and an area of high ground outside the village, Noyers-Bocage itself remained in German hands.The preliminary operations cost Second Army 3,500 casualties for no significant territorial gains but Greenline and Pomegranate were strategically successful. Reacting to the threats in the Odon Valley, the Germans retained the 2nd Panzer and 10th SS Panzer divisions in the front line and recalled the 9th SS Panzer Division from Corps reserve. The Germans suffered around 2,000 casualties. Terry Copp wrote that the fighting was "one of the bloodiest encounters of the campaign". During the late afternoon of 17 July, a patrolling Spitfire spotted a German staff car on the road near the village of Sainte-Foy-de-Montgommery. The fighter made a strafing attack driving the car off the road. Among its occupants was Field Marshal Erwin Rommel, the commander of Army Group B, who was seriously wounded, leaving Army Group B temporarily leaderless. Battle 18 July Shortly before dawn on 18 July, the Highland infantry in the south of the Orne bridgehead, quietly retired 0.5 mi (0.80 km) from the front line. At 05:45, 1,056 Handley Page Halifax and Avro Lancaster heavy bombers flying at 3,000 ft (910 m) dropped 4,800 long tons (4,900 t) of high explosive bombs around Colombelles, the steelworks, on the positions of the 21st Panzer Division and on the village of Cagny, reducing half of it to rubble. At 06:40 the British artillery opened fire and twenty minutes later, the second wave of bombers arrived. From 10,000–13,000 ft (3,000–4,000 m), American B-26 Marauders released 563 long tons (572 t) of fragmentation bombs on the 16th Luftwaffe Field Division, as fighter-bombers attacked German strong points and gun positions. During the 45-minute bombardment, the troops and tanks of the 11th Armoured Division moved out of their concentration areas towards the start line. H Hour was set for 07:45 and on schedule, the artillery switched to a creeping barrage, which moved ahead of the 11th Armoured Division. As the division moved off, more artillery opened fire on Cuverville, Demouville, Giberville, Liberville, Cagny and Émiéville and dropped harassing fire on targets as far south as Garcelles-Secqueville and Secqueville la Campagne. Fifteen minutes later, American heavy bombers dropped 1,340 long tons (1,360 t) of fragmentation bombs in the Troarn area and on the main German gun line on the Bourguébus Ridge. Only 25 bombers in the three waves were lost, all to German anti aircraft fire. Aerial support for the operation was then handed over to 800 fighter-bombers of 83 and 84 Groups.The bombing put the 22nd Panzer Regiment and the III Company, 503rd Heavy Panzer Battalion temporarily out of action, causing varying degrees of damage to their tanks. Some were overturned, some were destroyed and twenty were later found abandoned in bomb craters. Most of the German front line positions had been neutralised, with the survivors left "dazed and incoherent". Dust and smoke had impaired the ability of the bomber crews to identify all their targets and others on the periphery of the bombing zones had remained untouched. Cagny and Émiéville were extensively bombed but most of the defenders were unscathed and recovered in time to meet the British advance—both places having clear lines of fire, on the route the British were to take. The 503rd Heavy Tank Battalion rallied rapidly and got to work digging out their tanks. On the Bourguébus Ridge, a number of guns were destroyed by the bombing but most of the artillery and anti-tank guns remained intact. By 08:05, the 2nd Fife and Forfar Yeomanry and the 3rd Royal Tank Regiment of the 29th Armoured Brigade, had navigated minefields, to reach the Caen–Troarn railway line. The first phase of the rolling barrage ended at 08:30, by which time large numbers of prisoners from the 16th Luftwaffe Division had been rounded up. By the time the artillery resumed firing at 08:50, only the first armoured regiment and a portion of the second had crossed the line. Although opposition was still minimal and more prisoners were taken, the two regiments struggled to keep up with the barrage and were moving out of supporting range of their reserves. On schedule at 09:00 the barrage lifted and 35 minutes later, the lead squadrons reached the Caen–Vimont railway. In reserve, the 23rd Hussars had managed to clear the first railway line only to become embroiled in a 1+1⁄2-hour engagement with a battery of self-propelled guns of the 200th Assault Gun Battalion, that had been mistaken for Tiger tanks. As the 2nd Fife and Forfar Yeomanry advanced past Cagny, they were engaged by anti-tank guns in Cagny to the east. Within a few minutes at least twelve tanks were disabled. The Yeomanry pressed their advance south and were engaged by the main German gun line on the ridge, while the 3rd Royal Tank Regiment having shifted westward and exchanged fire with the German garrison in Grentheville, before moving around the village and advancing along the southern outskirts of Caen, towards Bras and Hubert-Folie. What had been conceived as an attack towards the Bourguébus Ridge by three armoured divisions, had become an unsupported advance by two tank regiments, out of sight of one other, against heavy German fire. By 11:15, the British reached the ridge and the villages of Bras and Bourguébus. Some losses were inflicted on the German tanks but attempts to advance further were met by determined opposition, including fire from the rear from pockets of resistance that had been bypassed.General Eberbach ordered a counter-attack, "not a defensive move but a full armoured charge". The 1st SS Panzer Division was to attack across the ridge, while in the Cagny area the 21st Panzer Division was to recover all lost ground. German tanks started to arrive on the ridge around noon and the British tank crews were soon reporting German tanks and guns everywhere. Hawker Typhoon fighter-bombers carrying RP-3 rockets were directed onto the ridge throughout the afternoon, delaying and eventually breaking up the 1st SS Panzer Division counter-attack. A final attempt to storm the ridge resulted in the loss of 16 British tanks and a small counter-attack during the afternoon was driven off, with the destruction of six German Panthers.Just before 10:00, the Guards Armoured Division caught up with the 11th Armoured Division and pressed on towards Cagny. By 12:00 the leading elements were halted, engaged in fighting. A German counter-attack against the 2nd Armoured Grenadier Guards by 19 tanks from the 21st Panzer Division and the Tigers of the 503rd Heavy Panzer Battalion, failed when the German tanks came under fire from their own guns and two Tigers were knocked out. An isolated Tiger II (King Tiger) attempting to manoeuvre out of danger, was caught by an Irish Guards Sherman tank that had also become detached from its unit. The Sherman crew fired into the Tiger and then rammed it; anti-tank fire from other British units then penetrated the Tiger's armour. Both crews abandoned their vehicles and most of the German crew was captured. The 503rd Heavy Panzer Battalion later attacked the Coldstream Guards but was forced to withdraw by massed anti-tank fire. It took the Guards the rest of the day to capture Cagny, which was found abandoned when infantry entered the village. Attempts to renew the advance were met by fierce German resistance. Starting last, the only element of the 7th Armoured Division to enter the battle was the 5th Royal Tank Regiment (5th RTR). At 17:00 near Cuverville it knocked out two Panzer IVs for the loss of four tanks and then cleared Grentheville which had been bypassed earlier in the day by the 3rd RTR and several prisoners were taken. A German counter-attack by six tanks petered out after two tanks each were destroyed. The 11th Armoured Division pulled back to the Caen–Vimont railway line for the evening and replacement tanks were brought forward for all divisions, with the 11th Armoured receiving priority. German recovery teams went forward to recover and repair as many of their tanks as possible, as few replacements were available. Unnoticed by the British, a gap had been created between Emièville and Troan. This was closed during the night by the 12th SS Panzer Division, which had lost ten tanks, en route, to air attacks. A number of minor German counter-attacks were launched from the ridge; one at dusk was broken up by British artillery and anti-tank fire, which destroyed a Panther and Tiger, another after dark led by a captured Sherman as a ruse, was repulsed after the Sherman and two Panthers were knocked out by a British anti-tank battery. During the night, German bombers dropped flares over the Orne bridges, which then came under aerial attack. One bridge was slightly damaged and the headquarters of the 11th Armoured Division was hit, as were some tank crews who had survived the fighting.In their fighting around Cagny, the Guards Armoured Division lost fifteen tanks destroyed and 45 tanks damaged. The 11th Armoured Division lost 126 tanks, although only forty were write-offs; the rest were damaged or had broken down. (The loss of 126 tanks of the 219–244 tanks that crossed the start line has been a common feature of accounts of Goodwood but the divisional commander, the VIII Corps historian and Chester Wilmot gave 126 tank losses. Michael Reynolds gave "...at least 125" and Christopher Dunphie 128 losses.) The armoured divisions suffered 521 casualties during the day, Guards Armoured Division suffered 127 casualties, the 7th Armoured Division had 48 casualties and the 11th Armoured Division had 336 casualties. On the eastern flank, the 3rd Infantry Division had a successful day, capturing all of its objectives except for Troarn. Operation Atlantic On the Canadian front, Operation Atlantic began at 08:15, with a rolling barrage and infantry and tanks crossed their start line twenty minutes later. At 08:40, British infantry from the 159th Infantry Brigade entered Cuverville; the village and its surrounding area were secured by 10:30 but patrols found Demouville firmly held and attempts to capture this second objective were delayed while the infantry reorganised. The rest of the day saw a slow southward advance, as numerous German positions were cleared. Linking up with their armoured support by nightfall, the infantry dug in around le Mesnil-Frèmentel. 19–20 July The German armour counter-attacked late in the afternoon and fighting continued along the high ground and around Hubert-Folie on 19 July and 20 July, bringing the attack to a halt. On 21 July, Dempsey started to secure his gains by substituting infantry for armour. Aftermath Analysis Tactically, the Germans contained the offensive, holding many of their main positions and preventing an Allied breakthrough, but they had been startled by the weight of the attack and preliminary aerial bombardment. It was clear that any defensive system less than 5 mi (8.0 km) deep could be overwhelmed at a stroke and the Germans could afford to man their defences in such depth only in the sector south of Caen. Goodwood resulted in the British extending the front line by 7 mi (11 km) to the east of Caen, with the penetration being as much as 12,000 yards (11 km; 6.8 mi) in some places; the southern suburbs of Caen were captured by the Canadians during Operation Atlantic.The attack reinforced the German view that the greatest danger was on the eastern flank. As German armoured reinforcements arrived in Normandy, they were drawn into defensive battles in the east and worn down. By the end of July only one and a half panzer divisions were facing American forces at the western end of the front, compared with six and a half facing the British and Canadians at the eastern end of the bridgehead. The German defence of Normandy was close to collapse when Operation Cobra breached the thin German defensive 'crust' in the west and few German mechanised units were available to counter-attack. Martin Blumenson, the American official historian, wrote after the war that had Goodwood created a breakthrough, "... Cobra would probably have been unnecessary". Goodwood inflicted substantial losses on the German defenders but not a shattering blow. The effect on the morale of the German commanders was greater and added to the loss of Rommel, who was wounded in an RAF air attack. Kluge lost his early optimism on being appointed to replace Rundstedt and wrote to Hitler on 21 July predicting an imminent collapse.Operation Goodwood was launched at a time of great frustration in the higher command of the Allies, which contributed to the controversy surrounding the operation. The Allied bridgehead was about 20 percent of the planned size, which led to congestion and some fear of a stalemate. Allied commanders had not been able to exploit their potentially decisive advantages in mobility during June and early July 1944. Much of the controversy surrounding the objectives of the battle originates from the conflicting messages given by Montgomery. He talked up the objectives of Goodwood to the press on the first day, later saying that this was propaganda to encourage the Germans to keep powerful units at the east end of the battlefield.In the planning of Goodwood, Montgomery appeared to promise that the attack would be a breakthrough and that when the VIII Corps failed to break-out, by some accounts the Supreme Commander, US General Dwight D. Eisenhower, felt he had been misled. While his intermittent communications to Supreme Headquarters Allied Expeditionary Force (SHAEF) appeared to promise a breakthrough, Montgomery was writing orders to his subordinates for a limited attack. Copies of orders forwarded to SHAEF called for an armoured division to take Falaise, a town far in the German rear. Three days prior to the attack, Montgomery revised the orders, eliminating Falaise as an objective but neglected to forward copies of the revision; Eisenhower was later furious at the result, which dogged Montgomery, as it allowed his detractors, especially Air Marshal Arthur Tedder, to imply that the operation was a failure.Stephen Biddle wrote that Goodwood was a significant tactical setback for Montgomery. Despite having preponderant force and air superiority, British progress was slow and ultimately failed to break through. Montgomery chose an unusually narrow spearhead of just 2 km (1.2 mi), which created a congested line of advance. British infantry was lacking in suitable junior officers and non-commissioned officers, which inhibited small-unit tactics. In Biddle's analysis, The British systematically failed to coordinate movement and suppressive fires after about mid-morning of the opening day.... The attack had by then moved beyond the reach of the British batteries on the northern side of the Orne River and the congestion in the march columns had kept the artillery from moving forward into supporting range.... The net result was thus an exposed, massed, nearly pure-tank assault pressing forward rapidly without supporting infantry or supporting suppressive fires. The Germans, by contrast, made great efforts to conceal their forces—moving under cover of dark, off the main roads, in small units and under radio silence. Casualties Simon Trew wrote that "the first estimates of Allied losses for Operation Goodwood appeared horrific, that Second Army had lost 4,011 men... ." In 2006, G. S. Jackson gave casualties in the armoured divisions from 18 to 19 July of 1,020 men. In 2001, Michael Reynolds quoted the 21st Army Group war diary of casualties in I and VIII Corps of 3,474 men. Operation Atlantic cost the Canadians from 1,349 to 1,965 casualties. Colonel Charles Stacey, the Canadian official historian, gave casualties of all Canadian units in Europe, for the four days' fighting of 1,965 in all categories; 441 men were killed or died of wounds. Simon Trew wrote that "no conclusive assessment can ever be made" in regards to the losses of both sides. In 2014, John Buckley gave a figure of 5,500 casualties during Goodwood and Atlantic.Over 2,000 German prisoners were taken and c. 100 tanks were destroyed. Jackson also wrote of c. 100 German tank losses. In the official history Major Lionel Ellis wrote that the 1st SS and 21st Panzer divisions lost 109 tanks on the first day of the battle. Reynolds recorded 77 German tanks or assault guns knocked out or damaged during the operation and that the claim of 75 tanks or assault guns destroyed—as stated in a post-war interview, by the commanding officer of the 11th Armoured Division, for a British staff college training film on the operation—"can be accepted as accurate". Michael Tamelander wrote in 2004 that Panzergruppe West recorded the loss of 75 tanks during the period from 16 to 21 July.British tank losses during Goodwood have been debated, with the loss ranging from 218 to 500. In addition to VIII Corps losses, about twenty tanks were lost in the flanking operations. Reynolds wrote that study of the records suggests that the maximum number of tanks lost during Operation Goodwood was 253, most of which were damaged rather than write-offs. Tamelander and Niklas Zetterling wrote that during Goodwood 469 tanks were lost by the armoured divisions (including 131 tanks on 19 July and 68 on 20 July) but that the majority could be repaired. Trew rejected those figures and wrote that after much investigation, VIII Corps losses amounted to 197 tanks on 18 July, 99 tanks on 19 July and 18 tanks on 20 July, "for a total of 314, of which 130 were completely destroyed". Trew wrote that "the tank strength returns for VIII Corps 18–21 July show a loss of 218 tanks (that could not be repaired or immediately replaced), including 145 tanks from 11th Armoured Division". In 2014 John Buckley wrote that 400 British tanks were knocked out and that many were recovered and put back into service, although the morale of some of the crews deteriorated. Notes Footnotes References Further reading External links Morss, R. "59th (Staffordshire) Division in WWII: Operation Pomegranate". Retrieved 18 May 2014. Zetterling: data on German losses in Normandy RAF photograph of Sannerville and Banneville la Campagne after the morning raid of 18 July 1944	location	{ "answer_start": [ 158 ], "text": [ "Normandy" ] }
Operation Goodwood was a British offensive during the Second World War, which took place between 18 and 20 July 1944 as part of the larger battle for Caen in Normandy, France. The objective of the operation was a limited attack to the south, from the Orne bridgehead, to capture the rest of Caen and the Bourguébus Ridge beyond. At least one historian has called the operation the largest tank battle that the British Army has ever fought.Goodwood was preceded by Operations Greenline and Pomegranate in the Second Battle of the Odon west of Caen, to divert German attention from the area east of Caen. Goodwood began when the British VIII Corps, with three armoured divisions, attacked to seize the German-held Bourguébus Ridge, the area between Bretteville-sur-Laize and Vimont and to inflict maximum casualties on the Germans. On 18 July, the British I Corps conducted an attack to secure a series of villages to the east of VIII Corps; to the west, the II Canadian Corps launched Operation Atlantic, synchronised with Goodwood, to capture the Caen suburbs south of the Orne River. When the operation ended on 20 July, the armoured divisions had broken through the outer German defences and advanced 7 mi (11 km) but had been stopped short of Bourguébus Ridge, only armoured cars having penetrated further south and beyond the ridge. While Goodwood failed in its primary aim, it forced the Germans to keep powerful formations opposite the British and Canadians on the eastern flank of the Normandy beachhead and Operation Cobra, the First US Army attack which began on 25 July, caused the weaker German defences opposite to collapse. Background Caen The historic Normandy town of Caen was a D-Day objective for the British 3rd Infantry Division, which landed on Sword Beach on 6 June 1944. The capture of Caen, while "ambitious", was called the most important D-Day objective assigned to I Corps (Lieutenant-General John Crocker). Operation Overlord called for Second Army to secure the city and then form a front line from Caumont-l'Éventé–south-east of Caen, to acquire space for airfields and to protect the left flank of the First US Army (Lieutenant General Omar N. Bradley), while it moved on Cherbourg. Possession of Caen and its surroundings would give the Second Army a staging area for a push south to capture Falaise, which could be used as the pivot for a swing left, to advance on Argentan and then towards the Touques River. The terrain between Caen and Vimont was especially promising, being open, dry and conducive to mobile operations. Since the Allied forces greatly outnumbered the Germans in tanks and mobile units, a fluid fast-moving battle was to their advantage.Hampered by congestion in the beachhead and forced to divert effort to attack strongly held German positions along the 9.3 mi (15.0 km) route to the town, the 3rd Infantry Division was unable to assault Caen in force and was stopped short of the outskirts. Follow-up attacks were unsuccessful as German resistance solidified; abandoning the direct approach, Operation Perch—a pincer attack by I Corps and XXX Corps—was launched on 7 June, to encircle Caen from the east and west. I Corps, striking south out of the Orne bridgehead, was halted by the 21st Panzer Division and the attack by XXX Corps bogged down in front of Tilly-sur-Seulles, west of Caen, against the Panzer Lehr Division. The 7th Armoured Division pushed through a gap in the German front line and tried to capture the town of Villers-Bocage in the German rear. The Battle of Villers-Bocage saw the vanguard of the 7th Armoured Division withdraw from the town but by 17 June, Panzer Lehr had been forced back and XXX Corps had taken Tilly-sur-Seulles. The British postponed plans for further offensive operations, including a second attack by the 7th Armoured Division, when a severe storm descended upon the English Channel on 19 June. The storm lasted for three days, significantly delayed the Allied build-up. Most of the landing craft and ships already at sea were driven back to ports in Britain; towed barges and other loads (including 2.5 mi (4.0 km) of floating roadways for the Mulberry harbours) were lost and 800 craft were stranded on the Normandy beaches, until the next high tides in July. Epsom, Windsor and Charnwood After a few days to recover from the storm, the British began Operation Epsom on 26 June. The newly arrived VIII Corps (Lieutenant-General Richard O'Connor), was to attack west of Caen, southwards across the Odon and Orne rivers, capture an area of high ground near Bretteville-sur-Laize, encircling the city. The attack was preceded by Operation Martlet, to secure the VIII Corps flank by capturing high ground on the right of the axis of advance. The Germans managed to contain the offensive by committing all their strength, including two panzer divisions just arrived in Normandy, earmarked for an offensive against British and American positions around Bayeux. Several days later, the Second Army made a frontal assault on Caen Operation Charnwood. The attack was preceded by Operation Windsor, to capture the airfield at Carpiquet just outside Caen. By 9 July, Caen north of the Orne and Odon rivers had been captured but German forces retained possession of the south bank and a number of important locations, including the Colombelles steel works, whose tall chimneys commanded the area. Shortly after the capture of northern Caen during Operation Charnwood, the British mounted a raid against the Colombelles steelworks complex to the north-east of the city, which was a failure. The factory area remained in German hands, its tall chimneys providing observation posts that overlooked the Orne bridgehead. At 01:00 on 11 July, elements of the 153rd (Highland) Infantry Brigade, supported by Sherman tanks of the 148th Regiment Royal Armoured Corps, moved against the German position. The intention was to secure the area for troops from the Royal Engineers to destroy the chimneys before retiring. At 05:00, the British force was ambushed by Tiger tanks and was forced to withdraw after losing nine tanks. The Second Army launched two preliminary operations; according to Montgomery, their purpose was to "engage the enemy in battle unceasingly; we must 'write off' his troops; and generally we must kill Germans". Historian Terry Copp called this the moment where the Normandy campaign became a battle of attrition. Montgomery On 10 July, General Bernard Montgomery, the commander of all the Allied ground forces in Normandy, held a meeting at his headquarters with Dempsey and Bradley. They discussed 21st Army Group operations, following the conclusion of Operation Charnwood and the failure of the First US Army break-out offensive. Montgomery approved Operation Cobra, an attack to be launched by the First US Army on 18 July. Montgomery ordered Dempsey to "go on hitting: drawing the German strength, especially the armour, onto yourself—so as to ease the way for Brad".In early July, Montgomery had been informed by the Adjutant-General to the Forces, Ronald Adam that due to the manpower shortage in Britain, the pool of replacements to maintain his infantry strength was nearly exhausted. Dempsey proposed an attack consisting solely of armoured divisions, a concept that contradicted Montgomery's policy of never employing an unbalanced force. By mid-July, the Second Army had 2,250 medium tanks and 400 light tanks in the bridgehead, of which 500 were in reserve to replace losses. The armoured element of the Second Army consisted of the Guards Armoured Division, 7th Armoured Division and the 11th Armoured Division and the 4th Armoured Brigade, 8th Armoured Brigade, 27th Armoured Brigade and 33rd Armoured brigades, the 31st and 34th Tank brigades and the 2nd Canadian Armoured Brigade.At 10:00 on 13 July, Dempsey met with Crocker, Lieutenant-General Simonds of II Canadian Corps and O'Connor. Later that day, the first written order for Operation Goodwood—named after the Glorious Goodwood race meetings—was issued. The document contained only preliminary instructions and general intentions; it was to stimulate detailed planning and alterations were expected. The order was also sent to senior planners in the United Kingdom so that air support for the operation could be secured. When VIII Corps had assembled in Normandy in mid-June, it was suggested that the corps be used to attack out of the Orne bridgehead, to outflank Caen from the east but Operation Dreadnought was cancelled when Dempsey and O'Connor doubted the feasibility of the operation. Prelude Goodwood plan In the outline for Goodwood, VIII Corps, with three armoured divisions, would attack southwards out of the Orne bridgehead, a pocket of ground east of the river taken by the Allies on D-Day. The 11th Armoured Division was to advance south-west over Bourguébus Ridge and the Caen–Falaise road, aiming for Bretteville-sur-Laize. The Guards Armoured Division was to push south-east to capture Vimont and Argences and the 7th Armoured Division, starting last, was to aim south for Falaise. The 3rd Infantry Division, supported by part of the 51st (Highland) Infantry Division, was to secure the eastern flank by capturing the area around Émiéville, Touffréville and Troarn. The II Canadian Corps would simultaneously launch Operation Atlantic a supporting attack on the VIII Corps western flank, to capture Caen south of the Orne river. The British and Canadian operations were tentatively scheduled for 18 July and Cobra was postponed for two days, to enable the First Army to secure its start line around Saint-Lô.Detailed planning began on Friday 14 July but the next day, Montgomery issued a written directive ordering Dempsey to change the plan from a "deep break-out" to a "limited attack". Anticipating that the Germans would be forced to commit their armoured reserves, rather than risk a massed British tank breakthrough, VIII Corps was instructed to "engage the German armour in battle and 'write it down' to such an extent that it is of no further value to the Germans". He was to take any opportunity to improve the Second Army's position—the orders stated that "a victory on the eastern flank will help us to gain what we want on the western flank"—but not to endanger its role as a "firm bastion" on which the success of the forthcoming American offensive would depend. The objectives of the three armoured divisions were amended to "dominate the area Bourguébus–Vimont–Bretteville", although it was intended that "armoured cars should push far to the south towards Falaise, spread[ing] alarm and despondency". The objectives for the II Canadian Corps remained unchanged and it was stressed that these were vital, only following their achievement would VIII Corps "'crack about' as the situation demands".The 11th Armoured Division was to lead the advance, screen Cagny and capture Bras, Hubert-Folie, Verrières and Fontenay-le-Marmion. Its armoured brigade was to bypass most of the German-held villages in its area, leaving them to be dealt with by follow-up waves. The 159th Infantry Brigade, was initially to act independently of the rest of the division and capture Cuverville and Démouville. The Guards Armoured Division, advancing behind the 11th Armoured Division, was to capture Cagny and Vimont. Starting last, the 7th Armoured Division was to move south beyond the Garcelles-Secqueville ridge. Further advances by the armoured divisions were to be conducted only on Dempsey's order. The detailed orders for the II Canadian Corps were issued a day later, to capture Colombelles, the remaining portion of Caen and then be ready to move on the strongly held Verrières (Bourguébus) Ridge. If the German front collapsed, a deeper advance would be considered.Second Army intelligence had formed a good estimate of the opposition Goodwood was likely to face, although the German positions beyond the first line of villages had to be inferred, mainly from inconclusive air reconnaissance. The German defensive line was believed to consist of two belts up to 4 mi (6.4 km) deep. Aware that the Germans were expecting a large attack out of the Orne bridgehead, the British anticipated meeting resistance from the 16th Luftwaffe Field Division bolstered by SS-Panzergrenadier Regiment 25 of the 12th SS Panzer Division Hitlerjugend. Signals intelligence ascertained that the 12th SS Panzer Division had been moved into reserve and although it was slow to discover that SS-Panzergrenadier Regiment 25 was not with the 16th Luftwaffe Field Division, having also been placed into reserve, this oversight was rectified before 18 July. Battle groups of the 21st Panzer Division with around 50 Panzer IV and 34 assault guns, were expected near Route nationale 13. The 1st SS Division Leibstandarte SS Adolf Hitler was identified in reserve with an estimated 40 Panther tanks and 60 Panzer IV and the presence of two heavy tank battalions equipped with Tiger tanks was established. German armoured strength was estimated at 230 tanks and artillery strength at 300 field and anti-tank guns. The Second Army believed that 90 guns were in the centre of the battle zone, 40 on the flanks and 20 defending the Caen–Vimont railway line. The British had also located a German gun line on the Bourguébus Ridge but its strength and gun positions were unknown. To mask the operational objectives, the Second Army initiated a deception plan that included diversionary attacks launched by XII and XXX Corps. The three armoured divisions moved to their staging positions west of the Orne only at night and in radio silence; artillery fire was used to mask the noise of the tank engines. During the hours of daylight all efforts were made to camouflage the new positions.For artillery support, Goodwood was allocated 760 guns,with 297,600 rounds of ammunition. 456 field pieces from 19 field regiments, 208 medium guns from 13 medium regiments, 48 heavy pieces from 3 heavy regiments and 48 heavy anti-aircraft guns from two heavy anti-aircraft regiments. The artillery was provided by I, VIII, XII Corps and II Canadian Corps as well as the 2nd Canadian Army Group Royal Artillery (AGRA) and the 4th AGRA. Each field gun was allocated 500 rounds, each medium piece 300 rounds and each heavy gun or howitzer 150 rounds. Prior to the assault these were to attempt to suppress German anti-tank and field artillery positions. During the attack they would provide the 11th Armoured Division with a rolling barrage and anti-aircraft defence. The guns would also assist the attacks launched by the 3rd Infantry and 2nd Canadian Infantry divisions and fire on targets as requested. Additional support would be provided by three ships of the Royal Navy, whose targets were German gun batteries located near the coast in the region of Cabourg and Franceville. The engineering resources of the Second Army, I and VIII corps and the divisional engineers worked from 13–16 July to build six roads from west of the Orne River to the start lines east of the river and the Caen Canal. Engineers from I Corps strengthened bridges and built two new sets of bridges across the Orne and the canal. The engineers were also to construct another two sets of bridges by the end of the first day. II Canadian Corps planned to construct up to three bridges across the Orne as quickly as possible to give I and VIII corps exclusive access to the river and the canal bridges north of Caen. Engineers from the 51st (Highland) Infantry Division, with a small detachment from the 3rd Infantry Division, were ordered to breach the German minefield in front of the Highland Division. This was largely accomplished during the night of 16/17 July, when they cleared and marked fourteen gaps. By the morning of 18 July, 19 40 ft (12 m)-wide gaps had been completed, each for one armoured regiment to pass through at a time.The 11th Armoured Division infantry brigade, with the divisional and 29th Armoured Brigade headquarters, crossed into the Orne bridgehead during the night of 16/17 July and the rest of the division followed the next night. The Guards and 7th Armoured divisions were held west of the river until the operation began. As the final elements of the 11th Armoured Division moved into position and the VIII Corps headquarters took up residence in Bény-sur-Mer, more gaps in the minefields were blown, the forward areas were signposted and routes to be taken marked with white tape. Allied air forces Augmenting the preliminary artillery bombardment, 2,077 heavy and medium bombers of the Royal Air Force (RAF) and United States Army Air Forces (USAAF) would attack in three waves, in the largest air raid launched in direct support of ground forces in the campaign so far. Speed was an essential part of the Goodwood plan and it was hoped that the aerial bombardment would pave the way for the 11th Armoured Division, rapidly to secure the Bourguébus Ridge. Dempsey believed that if the operation were to succeed, his tanks would need to be on the ridge by the first afternoon and cancelled a second attack by heavy bombers scheduled for the first afternoon; although this was to be in direct support of the advance towards the ridge, he was concerned that the 11th Armoured Division should not be delayed waiting for the strike. Close air support for Goodwood would be provided by No. 83 Group RAF, to neutralise German positions on the flanks of VIII Corps, strong points such as the village of Cagny, attacking German gun and reserve positions and the interdiction of German troop movements. Each of the VIII Corps brigade headquarters, was allocated a Forward Air Control Post. German preparations The Germans considered the Caen area to be the foundation of their position in Normandy and were determined to maintain a defensive arc from the English Channel to the west bank of the Orne. On 15 July, German military intelligence warned Panzer Group West that from 17 July, a British attack out of the Orne bridgehead was likely. It was thought that the British would push south-east towards Paris. General Heinrich Eberbach, the commanding officer of Panzer Group West, designed a defensive plan, with its details worked out by his two corps and six divisional commanders. A belt of at least 10 miles (16 km) depth was constructed, organised into four defence lines. Villages within the belt were fortified and anti-tank guns placed along its southern and eastern edges. To allow tanks to move freely within the belt, the Germans decided not to establish anti-tank minefields between each defensive line. On 16 July, several reconnaissance flights were mounted over the British front but most of these were driven off by anti-aircraft fire. As dark fell, camera-equipped aircraft managed to bring back photographs taken by the light of flares, which revealed a one-way flow of traffic over the Orne into the British bridgehead. Later that day, a British Spitfire was shot down over German lines while photographing defences; British artillery and fighters attempted to destroy the crashed aircraft without success. LXXXVI Corps, reinforced by much artillery, held the front line. The 346th Infantry Division was dug in from the coast to the north of Touffreville and the depleted 16th Luftwaffe Field Division held the next section from Touffreville to Colombelles. Kampfgruppe von Luck, a battle group formed around the 21st Panzer Division 125th Panzergrenadier Regiment, was placed behind these forces with around 30 assault guns. The 21st Panzer Division armoured elements, reinforced with the 503rd Heavy Panzer Battalion, which included ten King Tigers, were north-east of Cagny in a position to support Luck's men and to act as a general reserve and the rest of the divisional panzergrenadiers, with towed anti-tank guns and assault guns, were dug in amongst the villages of the Caen plain. The 21st Panzer Division reconnaissance and pioneer battalions, were positioned on the Bourguébus Ridge to protect the corps artillery, which consisted of around 48 field and medium guns with an equal number of Nebelwerfer rocket launchers. The LXXXVI Corps had 194 artillery pieces, 272 Nebelwerfers and 78 anti-aircraft and anti-tank 88 mm guns. One battery of four 88 mm anti-aircraft guns from the 2nd Flak-Sturm Regiment, was positioned in Cagny, while in the villages along the Bourguébus Ridge there was a screen of 44 x 88 mm anti-tank guns from the 200th Tank Destroyer Battalion. Most of the LXXXVI Corps artillery was beyond the ridge covering the Caen–Falaise road.Facing Caen to the west of the Caen–Falaise road was the I SS Panzer Corps. On 14 July, elements of the 272nd Infantry Division took over the defence of Vaucelles from the 1st SS Division Leibstandarte SS Adolf Hitler, who moved into local reserve between the village of Ifs and the east bank of the Orne. The following day the 12th SS Panzer Division was placed in Oberkommando der Wehrmacht (OKW) reserve to rest and refit and—on Hitler's orders—to be in a position to meet a feared second Allied landing between the Orne and Seine rivers. The divisional artillery regiment and anti-aircraft battalion remained behind to support the 272nd Infantry Division and two battle groups were detached from the division. Kampfgruppe Waldmüller was moved close to Falaise and Kampfgruppe Wünsche to Lisieux, 40 kilometres (25 mi) east of Caen. Although Kampfgruppe Waldmüller was later ordered to rejoin the rest of the division at Lisieux, on 17 July Eberbach halted this move. Preliminary operations Operation Greenline Operation Greenline was launched by XII Corps during the evening of 15 July, with the 15th (Scottish) Infantry Division reinforced by a brigade of 53rd (Welsh) Infantry Division, the 34th Tank Brigade, 43rd (Wessex) Infantry Division and the 53rd (Welsh) Infantry Division, minus one brigade. Greenline was intended to convince the German command that the main British assault would be launched west of the Orne, through the positions held by XII Corps and to tie down the 9th and 10th SS Panzer divisions, so that they could not oppose Goodwood or Cobra. Supported by 450 guns, the British attack made use of artificial moonlight and started well despite disruption caused by German artillery fire. By dawn XII Corps had captured several of its objectives including the important height of Hill 113, although the much-contested Hill 112 remained in German hands. By committing the 9th SS Panzer Division, the Germans managed by the end of the day to largely restore their line, although a counter-attack against Hill 113 failed. Attacks next day by XII Corps gained no further ground and during the evening of 17 July, the operation was closed down and the British force on Hill 113 withdrawn. Operation Pomegranate Operation Pomegranate began on 16 July, in which XXX Corps was to capture several important villages. On the first day British infantry seized a key objective and took 300 prisoners but the next day there was much inconclusive fighting on the outskirts of Noyers-Bocage and Elements of the 9th SS Panzer Division were committed to the village defence. Although the British took control of the railway station and an area of high ground outside the village, Noyers-Bocage itself remained in German hands.The preliminary operations cost Second Army 3,500 casualties for no significant territorial gains but Greenline and Pomegranate were strategically successful. Reacting to the threats in the Odon Valley, the Germans retained the 2nd Panzer and 10th SS Panzer divisions in the front line and recalled the 9th SS Panzer Division from Corps reserve. The Germans suffered around 2,000 casualties. Terry Copp wrote that the fighting was "one of the bloodiest encounters of the campaign". During the late afternoon of 17 July, a patrolling Spitfire spotted a German staff car on the road near the village of Sainte-Foy-de-Montgommery. The fighter made a strafing attack driving the car off the road. Among its occupants was Field Marshal Erwin Rommel, the commander of Army Group B, who was seriously wounded, leaving Army Group B temporarily leaderless. Battle 18 July Shortly before dawn on 18 July, the Highland infantry in the south of the Orne bridgehead, quietly retired 0.5 mi (0.80 km) from the front line. At 05:45, 1,056 Handley Page Halifax and Avro Lancaster heavy bombers flying at 3,000 ft (910 m) dropped 4,800 long tons (4,900 t) of high explosive bombs around Colombelles, the steelworks, on the positions of the 21st Panzer Division and on the village of Cagny, reducing half of it to rubble. At 06:40 the British artillery opened fire and twenty minutes later, the second wave of bombers arrived. From 10,000–13,000 ft (3,000–4,000 m), American B-26 Marauders released 563 long tons (572 t) of fragmentation bombs on the 16th Luftwaffe Field Division, as fighter-bombers attacked German strong points and gun positions. During the 45-minute bombardment, the troops and tanks of the 11th Armoured Division moved out of their concentration areas towards the start line. H Hour was set for 07:45 and on schedule, the artillery switched to a creeping barrage, which moved ahead of the 11th Armoured Division. As the division moved off, more artillery opened fire on Cuverville, Demouville, Giberville, Liberville, Cagny and Émiéville and dropped harassing fire on targets as far south as Garcelles-Secqueville and Secqueville la Campagne. Fifteen minutes later, American heavy bombers dropped 1,340 long tons (1,360 t) of fragmentation bombs in the Troarn area and on the main German gun line on the Bourguébus Ridge. Only 25 bombers in the three waves were lost, all to German anti aircraft fire. Aerial support for the operation was then handed over to 800 fighter-bombers of 83 and 84 Groups.The bombing put the 22nd Panzer Regiment and the III Company, 503rd Heavy Panzer Battalion temporarily out of action, causing varying degrees of damage to their tanks. Some were overturned, some were destroyed and twenty were later found abandoned in bomb craters. Most of the German front line positions had been neutralised, with the survivors left "dazed and incoherent". Dust and smoke had impaired the ability of the bomber crews to identify all their targets and others on the periphery of the bombing zones had remained untouched. Cagny and Émiéville were extensively bombed but most of the defenders were unscathed and recovered in time to meet the British advance—both places having clear lines of fire, on the route the British were to take. The 503rd Heavy Tank Battalion rallied rapidly and got to work digging out their tanks. On the Bourguébus Ridge, a number of guns were destroyed by the bombing but most of the artillery and anti-tank guns remained intact. By 08:05, the 2nd Fife and Forfar Yeomanry and the 3rd Royal Tank Regiment of the 29th Armoured Brigade, had navigated minefields, to reach the Caen–Troarn railway line. The first phase of the rolling barrage ended at 08:30, by which time large numbers of prisoners from the 16th Luftwaffe Division had been rounded up. By the time the artillery resumed firing at 08:50, only the first armoured regiment and a portion of the second had crossed the line. Although opposition was still minimal and more prisoners were taken, the two regiments struggled to keep up with the barrage and were moving out of supporting range of their reserves. On schedule at 09:00 the barrage lifted and 35 minutes later, the lead squadrons reached the Caen–Vimont railway. In reserve, the 23rd Hussars had managed to clear the first railway line only to become embroiled in a 1+1⁄2-hour engagement with a battery of self-propelled guns of the 200th Assault Gun Battalion, that had been mistaken for Tiger tanks. As the 2nd Fife and Forfar Yeomanry advanced past Cagny, they were engaged by anti-tank guns in Cagny to the east. Within a few minutes at least twelve tanks were disabled. The Yeomanry pressed their advance south and were engaged by the main German gun line on the ridge, while the 3rd Royal Tank Regiment having shifted westward and exchanged fire with the German garrison in Grentheville, before moving around the village and advancing along the southern outskirts of Caen, towards Bras and Hubert-Folie. What had been conceived as an attack towards the Bourguébus Ridge by three armoured divisions, had become an unsupported advance by two tank regiments, out of sight of one other, against heavy German fire. By 11:15, the British reached the ridge and the villages of Bras and Bourguébus. Some losses were inflicted on the German tanks but attempts to advance further were met by determined opposition, including fire from the rear from pockets of resistance that had been bypassed.General Eberbach ordered a counter-attack, "not a defensive move but a full armoured charge". The 1st SS Panzer Division was to attack across the ridge, while in the Cagny area the 21st Panzer Division was to recover all lost ground. German tanks started to arrive on the ridge around noon and the British tank crews were soon reporting German tanks and guns everywhere. Hawker Typhoon fighter-bombers carrying RP-3 rockets were directed onto the ridge throughout the afternoon, delaying and eventually breaking up the 1st SS Panzer Division counter-attack. A final attempt to storm the ridge resulted in the loss of 16 British tanks and a small counter-attack during the afternoon was driven off, with the destruction of six German Panthers.Just before 10:00, the Guards Armoured Division caught up with the 11th Armoured Division and pressed on towards Cagny. By 12:00 the leading elements were halted, engaged in fighting. A German counter-attack against the 2nd Armoured Grenadier Guards by 19 tanks from the 21st Panzer Division and the Tigers of the 503rd Heavy Panzer Battalion, failed when the German tanks came under fire from their own guns and two Tigers were knocked out. An isolated Tiger II (King Tiger) attempting to manoeuvre out of danger, was caught by an Irish Guards Sherman tank that had also become detached from its unit. The Sherman crew fired into the Tiger and then rammed it; anti-tank fire from other British units then penetrated the Tiger's armour. Both crews abandoned their vehicles and most of the German crew was captured. The 503rd Heavy Panzer Battalion later attacked the Coldstream Guards but was forced to withdraw by massed anti-tank fire. It took the Guards the rest of the day to capture Cagny, which was found abandoned when infantry entered the village. Attempts to renew the advance were met by fierce German resistance. Starting last, the only element of the 7th Armoured Division to enter the battle was the 5th Royal Tank Regiment (5th RTR). At 17:00 near Cuverville it knocked out two Panzer IVs for the loss of four tanks and then cleared Grentheville which had been bypassed earlier in the day by the 3rd RTR and several prisoners were taken. A German counter-attack by six tanks petered out after two tanks each were destroyed. The 11th Armoured Division pulled back to the Caen–Vimont railway line for the evening and replacement tanks were brought forward for all divisions, with the 11th Armoured receiving priority. German recovery teams went forward to recover and repair as many of their tanks as possible, as few replacements were available. Unnoticed by the British, a gap had been created between Emièville and Troan. This was closed during the night by the 12th SS Panzer Division, which had lost ten tanks, en route, to air attacks. A number of minor German counter-attacks were launched from the ridge; one at dusk was broken up by British artillery and anti-tank fire, which destroyed a Panther and Tiger, another after dark led by a captured Sherman as a ruse, was repulsed after the Sherman and two Panthers were knocked out by a British anti-tank battery. During the night, German bombers dropped flares over the Orne bridges, which then came under aerial attack. One bridge was slightly damaged and the headquarters of the 11th Armoured Division was hit, as were some tank crews who had survived the fighting.In their fighting around Cagny, the Guards Armoured Division lost fifteen tanks destroyed and 45 tanks damaged. The 11th Armoured Division lost 126 tanks, although only forty were write-offs; the rest were damaged or had broken down. (The loss of 126 tanks of the 219–244 tanks that crossed the start line has been a common feature of accounts of Goodwood but the divisional commander, the VIII Corps historian and Chester Wilmot gave 126 tank losses. Michael Reynolds gave "...at least 125" and Christopher Dunphie 128 losses.) The armoured divisions suffered 521 casualties during the day, Guards Armoured Division suffered 127 casualties, the 7th Armoured Division had 48 casualties and the 11th Armoured Division had 336 casualties. On the eastern flank, the 3rd Infantry Division had a successful day, capturing all of its objectives except for Troarn. Operation Atlantic On the Canadian front, Operation Atlantic began at 08:15, with a rolling barrage and infantry and tanks crossed their start line twenty minutes later. At 08:40, British infantry from the 159th Infantry Brigade entered Cuverville; the village and its surrounding area were secured by 10:30 but patrols found Demouville firmly held and attempts to capture this second objective were delayed while the infantry reorganised. The rest of the day saw a slow southward advance, as numerous German positions were cleared. Linking up with their armoured support by nightfall, the infantry dug in around le Mesnil-Frèmentel. 19–20 July The German armour counter-attacked late in the afternoon and fighting continued along the high ground and around Hubert-Folie on 19 July and 20 July, bringing the attack to a halt. On 21 July, Dempsey started to secure his gains by substituting infantry for armour. Aftermath Analysis Tactically, the Germans contained the offensive, holding many of their main positions and preventing an Allied breakthrough, but they had been startled by the weight of the attack and preliminary aerial bombardment. It was clear that any defensive system less than 5 mi (8.0 km) deep could be overwhelmed at a stroke and the Germans could afford to man their defences in such depth only in the sector south of Caen. Goodwood resulted in the British extending the front line by 7 mi (11 km) to the east of Caen, with the penetration being as much as 12,000 yards (11 km; 6.8 mi) in some places; the southern suburbs of Caen were captured by the Canadians during Operation Atlantic.The attack reinforced the German view that the greatest danger was on the eastern flank. As German armoured reinforcements arrived in Normandy, they were drawn into defensive battles in the east and worn down. By the end of July only one and a half panzer divisions were facing American forces at the western end of the front, compared with six and a half facing the British and Canadians at the eastern end of the bridgehead. The German defence of Normandy was close to collapse when Operation Cobra breached the thin German defensive 'crust' in the west and few German mechanised units were available to counter-attack. Martin Blumenson, the American official historian, wrote after the war that had Goodwood created a breakthrough, "... Cobra would probably have been unnecessary". Goodwood inflicted substantial losses on the German defenders but not a shattering blow. The effect on the morale of the German commanders was greater and added to the loss of Rommel, who was wounded in an RAF air attack. Kluge lost his early optimism on being appointed to replace Rundstedt and wrote to Hitler on 21 July predicting an imminent collapse.Operation Goodwood was launched at a time of great frustration in the higher command of the Allies, which contributed to the controversy surrounding the operation. The Allied bridgehead was about 20 percent of the planned size, which led to congestion and some fear of a stalemate. Allied commanders had not been able to exploit their potentially decisive advantages in mobility during June and early July 1944. Much of the controversy surrounding the objectives of the battle originates from the conflicting messages given by Montgomery. He talked up the objectives of Goodwood to the press on the first day, later saying that this was propaganda to encourage the Germans to keep powerful units at the east end of the battlefield.In the planning of Goodwood, Montgomery appeared to promise that the attack would be a breakthrough and that when the VIII Corps failed to break-out, by some accounts the Supreme Commander, US General Dwight D. Eisenhower, felt he had been misled. While his intermittent communications to Supreme Headquarters Allied Expeditionary Force (SHAEF) appeared to promise a breakthrough, Montgomery was writing orders to his subordinates for a limited attack. Copies of orders forwarded to SHAEF called for an armoured division to take Falaise, a town far in the German rear. Three days prior to the attack, Montgomery revised the orders, eliminating Falaise as an objective but neglected to forward copies of the revision; Eisenhower was later furious at the result, which dogged Montgomery, as it allowed his detractors, especially Air Marshal Arthur Tedder, to imply that the operation was a failure.Stephen Biddle wrote that Goodwood was a significant tactical setback for Montgomery. Despite having preponderant force and air superiority, British progress was slow and ultimately failed to break through. Montgomery chose an unusually narrow spearhead of just 2 km (1.2 mi), which created a congested line of advance. British infantry was lacking in suitable junior officers and non-commissioned officers, which inhibited small-unit tactics. In Biddle's analysis, The British systematically failed to coordinate movement and suppressive fires after about mid-morning of the opening day.... The attack had by then moved beyond the reach of the British batteries on the northern side of the Orne River and the congestion in the march columns had kept the artillery from moving forward into supporting range.... The net result was thus an exposed, massed, nearly pure-tank assault pressing forward rapidly without supporting infantry or supporting suppressive fires. The Germans, by contrast, made great efforts to conceal their forces—moving under cover of dark, off the main roads, in small units and under radio silence. Casualties Simon Trew wrote that "the first estimates of Allied losses for Operation Goodwood appeared horrific, that Second Army had lost 4,011 men... ." In 2006, G. S. Jackson gave casualties in the armoured divisions from 18 to 19 July of 1,020 men. In 2001, Michael Reynolds quoted the 21st Army Group war diary of casualties in I and VIII Corps of 3,474 men. Operation Atlantic cost the Canadians from 1,349 to 1,965 casualties. Colonel Charles Stacey, the Canadian official historian, gave casualties of all Canadian units in Europe, for the four days' fighting of 1,965 in all categories; 441 men were killed or died of wounds. Simon Trew wrote that "no conclusive assessment can ever be made" in regards to the losses of both sides. In 2014, John Buckley gave a figure of 5,500 casualties during Goodwood and Atlantic.Over 2,000 German prisoners were taken and c. 100 tanks were destroyed. Jackson also wrote of c. 100 German tank losses. In the official history Major Lionel Ellis wrote that the 1st SS and 21st Panzer divisions lost 109 tanks on the first day of the battle. Reynolds recorded 77 German tanks or assault guns knocked out or damaged during the operation and that the claim of 75 tanks or assault guns destroyed—as stated in a post-war interview, by the commanding officer of the 11th Armoured Division, for a British staff college training film on the operation—"can be accepted as accurate". Michael Tamelander wrote in 2004 that Panzergruppe West recorded the loss of 75 tanks during the period from 16 to 21 July.British tank losses during Goodwood have been debated, with the loss ranging from 218 to 500. In addition to VIII Corps losses, about twenty tanks were lost in the flanking operations. Reynolds wrote that study of the records suggests that the maximum number of tanks lost during Operation Goodwood was 253, most of which were damaged rather than write-offs. Tamelander and Niklas Zetterling wrote that during Goodwood 469 tanks were lost by the armoured divisions (including 131 tanks on 19 July and 68 on 20 July) but that the majority could be repaired. Trew rejected those figures and wrote that after much investigation, VIII Corps losses amounted to 197 tanks on 18 July, 99 tanks on 19 July and 18 tanks on 20 July, "for a total of 314, of which 130 were completely destroyed". Trew wrote that "the tank strength returns for VIII Corps 18–21 July show a loss of 218 tanks (that could not be repaired or immediately replaced), including 145 tanks from 11th Armoured Division". In 2014 John Buckley wrote that 400 British tanks were knocked out and that many were recovered and put back into service, although the morale of some of the crews deteriorated. Notes Footnotes References Further reading External links Morss, R. "59th (Staffordshire) Division in WWII: Operation Pomegranate". Retrieved 18 May 2014. Zetterling: data on German losses in Normandy RAF photograph of Sannerville and Banneville la Campagne after the morning raid of 18 July 1944	Commons category	{ "answer_start": [ 0 ], "text": [ "Operation Goodwood" ] }
Operation Goodwood was a British offensive during the Second World War, which took place between 18 and 20 July 1944 as part of the larger battle for Caen in Normandy, France. The objective of the operation was a limited attack to the south, from the Orne bridgehead, to capture the rest of Caen and the Bourguébus Ridge beyond. At least one historian has called the operation the largest tank battle that the British Army has ever fought.Goodwood was preceded by Operations Greenline and Pomegranate in the Second Battle of the Odon west of Caen, to divert German attention from the area east of Caen. Goodwood began when the British VIII Corps, with three armoured divisions, attacked to seize the German-held Bourguébus Ridge, the area between Bretteville-sur-Laize and Vimont and to inflict maximum casualties on the Germans. On 18 July, the British I Corps conducted an attack to secure a series of villages to the east of VIII Corps; to the west, the II Canadian Corps launched Operation Atlantic, synchronised with Goodwood, to capture the Caen suburbs south of the Orne River. When the operation ended on 20 July, the armoured divisions had broken through the outer German defences and advanced 7 mi (11 km) but had been stopped short of Bourguébus Ridge, only armoured cars having penetrated further south and beyond the ridge. While Goodwood failed in its primary aim, it forced the Germans to keep powerful formations opposite the British and Canadians on the eastern flank of the Normandy beachhead and Operation Cobra, the First US Army attack which began on 25 July, caused the weaker German defences opposite to collapse. Background Caen The historic Normandy town of Caen was a D-Day objective for the British 3rd Infantry Division, which landed on Sword Beach on 6 June 1944. The capture of Caen, while "ambitious", was called the most important D-Day objective assigned to I Corps (Lieutenant-General John Crocker). Operation Overlord called for Second Army to secure the city and then form a front line from Caumont-l'Éventé–south-east of Caen, to acquire space for airfields and to protect the left flank of the First US Army (Lieutenant General Omar N. Bradley), while it moved on Cherbourg. Possession of Caen and its surroundings would give the Second Army a staging area for a push south to capture Falaise, which could be used as the pivot for a swing left, to advance on Argentan and then towards the Touques River. The terrain between Caen and Vimont was especially promising, being open, dry and conducive to mobile operations. Since the Allied forces greatly outnumbered the Germans in tanks and mobile units, a fluid fast-moving battle was to their advantage.Hampered by congestion in the beachhead and forced to divert effort to attack strongly held German positions along the 9.3 mi (15.0 km) route to the town, the 3rd Infantry Division was unable to assault Caen in force and was stopped short of the outskirts. Follow-up attacks were unsuccessful as German resistance solidified; abandoning the direct approach, Operation Perch—a pincer attack by I Corps and XXX Corps—was launched on 7 June, to encircle Caen from the east and west. I Corps, striking south out of the Orne bridgehead, was halted by the 21st Panzer Division and the attack by XXX Corps bogged down in front of Tilly-sur-Seulles, west of Caen, against the Panzer Lehr Division. The 7th Armoured Division pushed through a gap in the German front line and tried to capture the town of Villers-Bocage in the German rear. The Battle of Villers-Bocage saw the vanguard of the 7th Armoured Division withdraw from the town but by 17 June, Panzer Lehr had been forced back and XXX Corps had taken Tilly-sur-Seulles. The British postponed plans for further offensive operations, including a second attack by the 7th Armoured Division, when a severe storm descended upon the English Channel on 19 June. The storm lasted for three days, significantly delayed the Allied build-up. Most of the landing craft and ships already at sea were driven back to ports in Britain; towed barges and other loads (including 2.5 mi (4.0 km) of floating roadways for the Mulberry harbours) were lost and 800 craft were stranded on the Normandy beaches, until the next high tides in July. Epsom, Windsor and Charnwood After a few days to recover from the storm, the British began Operation Epsom on 26 June. The newly arrived VIII Corps (Lieutenant-General Richard O'Connor), was to attack west of Caen, southwards across the Odon and Orne rivers, capture an area of high ground near Bretteville-sur-Laize, encircling the city. The attack was preceded by Operation Martlet, to secure the VIII Corps flank by capturing high ground on the right of the axis of advance. The Germans managed to contain the offensive by committing all their strength, including two panzer divisions just arrived in Normandy, earmarked for an offensive against British and American positions around Bayeux. Several days later, the Second Army made a frontal assault on Caen Operation Charnwood. The attack was preceded by Operation Windsor, to capture the airfield at Carpiquet just outside Caen. By 9 July, Caen north of the Orne and Odon rivers had been captured but German forces retained possession of the south bank and a number of important locations, including the Colombelles steel works, whose tall chimneys commanded the area. Shortly after the capture of northern Caen during Operation Charnwood, the British mounted a raid against the Colombelles steelworks complex to the north-east of the city, which was a failure. The factory area remained in German hands, its tall chimneys providing observation posts that overlooked the Orne bridgehead. At 01:00 on 11 July, elements of the 153rd (Highland) Infantry Brigade, supported by Sherman tanks of the 148th Regiment Royal Armoured Corps, moved against the German position. The intention was to secure the area for troops from the Royal Engineers to destroy the chimneys before retiring. At 05:00, the British force was ambushed by Tiger tanks and was forced to withdraw after losing nine tanks. The Second Army launched two preliminary operations; according to Montgomery, their purpose was to "engage the enemy in battle unceasingly; we must 'write off' his troops; and generally we must kill Germans". Historian Terry Copp called this the moment where the Normandy campaign became a battle of attrition. Montgomery On 10 July, General Bernard Montgomery, the commander of all the Allied ground forces in Normandy, held a meeting at his headquarters with Dempsey and Bradley. They discussed 21st Army Group operations, following the conclusion of Operation Charnwood and the failure of the First US Army break-out offensive. Montgomery approved Operation Cobra, an attack to be launched by the First US Army on 18 July. Montgomery ordered Dempsey to "go on hitting: drawing the German strength, especially the armour, onto yourself—so as to ease the way for Brad".In early July, Montgomery had been informed by the Adjutant-General to the Forces, Ronald Adam that due to the manpower shortage in Britain, the pool of replacements to maintain his infantry strength was nearly exhausted. Dempsey proposed an attack consisting solely of armoured divisions, a concept that contradicted Montgomery's policy of never employing an unbalanced force. By mid-July, the Second Army had 2,250 medium tanks and 400 light tanks in the bridgehead, of which 500 were in reserve to replace losses. The armoured element of the Second Army consisted of the Guards Armoured Division, 7th Armoured Division and the 11th Armoured Division and the 4th Armoured Brigade, 8th Armoured Brigade, 27th Armoured Brigade and 33rd Armoured brigades, the 31st and 34th Tank brigades and the 2nd Canadian Armoured Brigade.At 10:00 on 13 July, Dempsey met with Crocker, Lieutenant-General Simonds of II Canadian Corps and O'Connor. Later that day, the first written order for Operation Goodwood—named after the Glorious Goodwood race meetings—was issued. The document contained only preliminary instructions and general intentions; it was to stimulate detailed planning and alterations were expected. The order was also sent to senior planners in the United Kingdom so that air support for the operation could be secured. When VIII Corps had assembled in Normandy in mid-June, it was suggested that the corps be used to attack out of the Orne bridgehead, to outflank Caen from the east but Operation Dreadnought was cancelled when Dempsey and O'Connor doubted the feasibility of the operation. Prelude Goodwood plan In the outline for Goodwood, VIII Corps, with three armoured divisions, would attack southwards out of the Orne bridgehead, a pocket of ground east of the river taken by the Allies on D-Day. The 11th Armoured Division was to advance south-west over Bourguébus Ridge and the Caen–Falaise road, aiming for Bretteville-sur-Laize. The Guards Armoured Division was to push south-east to capture Vimont and Argences and the 7th Armoured Division, starting last, was to aim south for Falaise. The 3rd Infantry Division, supported by part of the 51st (Highland) Infantry Division, was to secure the eastern flank by capturing the area around Émiéville, Touffréville and Troarn. The II Canadian Corps would simultaneously launch Operation Atlantic a supporting attack on the VIII Corps western flank, to capture Caen south of the Orne river. The British and Canadian operations were tentatively scheduled for 18 July and Cobra was postponed for two days, to enable the First Army to secure its start line around Saint-Lô.Detailed planning began on Friday 14 July but the next day, Montgomery issued a written directive ordering Dempsey to change the plan from a "deep break-out" to a "limited attack". Anticipating that the Germans would be forced to commit their armoured reserves, rather than risk a massed British tank breakthrough, VIII Corps was instructed to "engage the German armour in battle and 'write it down' to such an extent that it is of no further value to the Germans". He was to take any opportunity to improve the Second Army's position—the orders stated that "a victory on the eastern flank will help us to gain what we want on the western flank"—but not to endanger its role as a "firm bastion" on which the success of the forthcoming American offensive would depend. The objectives of the three armoured divisions were amended to "dominate the area Bourguébus–Vimont–Bretteville", although it was intended that "armoured cars should push far to the south towards Falaise, spread[ing] alarm and despondency". The objectives for the II Canadian Corps remained unchanged and it was stressed that these were vital, only following their achievement would VIII Corps "'crack about' as the situation demands".The 11th Armoured Division was to lead the advance, screen Cagny and capture Bras, Hubert-Folie, Verrières and Fontenay-le-Marmion. Its armoured brigade was to bypass most of the German-held villages in its area, leaving them to be dealt with by follow-up waves. The 159th Infantry Brigade, was initially to act independently of the rest of the division and capture Cuverville and Démouville. The Guards Armoured Division, advancing behind the 11th Armoured Division, was to capture Cagny and Vimont. Starting last, the 7th Armoured Division was to move south beyond the Garcelles-Secqueville ridge. Further advances by the armoured divisions were to be conducted only on Dempsey's order. The detailed orders for the II Canadian Corps were issued a day later, to capture Colombelles, the remaining portion of Caen and then be ready to move on the strongly held Verrières (Bourguébus) Ridge. If the German front collapsed, a deeper advance would be considered.Second Army intelligence had formed a good estimate of the opposition Goodwood was likely to face, although the German positions beyond the first line of villages had to be inferred, mainly from inconclusive air reconnaissance. The German defensive line was believed to consist of two belts up to 4 mi (6.4 km) deep. Aware that the Germans were expecting a large attack out of the Orne bridgehead, the British anticipated meeting resistance from the 16th Luftwaffe Field Division bolstered by SS-Panzergrenadier Regiment 25 of the 12th SS Panzer Division Hitlerjugend. Signals intelligence ascertained that the 12th SS Panzer Division had been moved into reserve and although it was slow to discover that SS-Panzergrenadier Regiment 25 was not with the 16th Luftwaffe Field Division, having also been placed into reserve, this oversight was rectified before 18 July. Battle groups of the 21st Panzer Division with around 50 Panzer IV and 34 assault guns, were expected near Route nationale 13. The 1st SS Division Leibstandarte SS Adolf Hitler was identified in reserve with an estimated 40 Panther tanks and 60 Panzer IV and the presence of two heavy tank battalions equipped with Tiger tanks was established. German armoured strength was estimated at 230 tanks and artillery strength at 300 field and anti-tank guns. The Second Army believed that 90 guns were in the centre of the battle zone, 40 on the flanks and 20 defending the Caen–Vimont railway line. The British had also located a German gun line on the Bourguébus Ridge but its strength and gun positions were unknown. To mask the operational objectives, the Second Army initiated a deception plan that included diversionary attacks launched by XII and XXX Corps. The three armoured divisions moved to their staging positions west of the Orne only at night and in radio silence; artillery fire was used to mask the noise of the tank engines. During the hours of daylight all efforts were made to camouflage the new positions.For artillery support, Goodwood was allocated 760 guns,with 297,600 rounds of ammunition. 456 field pieces from 19 field regiments, 208 medium guns from 13 medium regiments, 48 heavy pieces from 3 heavy regiments and 48 heavy anti-aircraft guns from two heavy anti-aircraft regiments. The artillery was provided by I, VIII, XII Corps and II Canadian Corps as well as the 2nd Canadian Army Group Royal Artillery (AGRA) and the 4th AGRA. Each field gun was allocated 500 rounds, each medium piece 300 rounds and each heavy gun or howitzer 150 rounds. Prior to the assault these were to attempt to suppress German anti-tank and field artillery positions. During the attack they would provide the 11th Armoured Division with a rolling barrage and anti-aircraft defence. The guns would also assist the attacks launched by the 3rd Infantry and 2nd Canadian Infantry divisions and fire on targets as requested. Additional support would be provided by three ships of the Royal Navy, whose targets were German gun batteries located near the coast in the region of Cabourg and Franceville. The engineering resources of the Second Army, I and VIII corps and the divisional engineers worked from 13–16 July to build six roads from west of the Orne River to the start lines east of the river and the Caen Canal. Engineers from I Corps strengthened bridges and built two new sets of bridges across the Orne and the canal. The engineers were also to construct another two sets of bridges by the end of the first day. II Canadian Corps planned to construct up to three bridges across the Orne as quickly as possible to give I and VIII corps exclusive access to the river and the canal bridges north of Caen. Engineers from the 51st (Highland) Infantry Division, with a small detachment from the 3rd Infantry Division, were ordered to breach the German minefield in front of the Highland Division. This was largely accomplished during the night of 16/17 July, when they cleared and marked fourteen gaps. By the morning of 18 July, 19 40 ft (12 m)-wide gaps had been completed, each for one armoured regiment to pass through at a time.The 11th Armoured Division infantry brigade, with the divisional and 29th Armoured Brigade headquarters, crossed into the Orne bridgehead during the night of 16/17 July and the rest of the division followed the next night. The Guards and 7th Armoured divisions were held west of the river until the operation began. As the final elements of the 11th Armoured Division moved into position and the VIII Corps headquarters took up residence in Bény-sur-Mer, more gaps in the minefields were blown, the forward areas were signposted and routes to be taken marked with white tape. Allied air forces Augmenting the preliminary artillery bombardment, 2,077 heavy and medium bombers of the Royal Air Force (RAF) and United States Army Air Forces (USAAF) would attack in three waves, in the largest air raid launched in direct support of ground forces in the campaign so far. Speed was an essential part of the Goodwood plan and it was hoped that the aerial bombardment would pave the way for the 11th Armoured Division, rapidly to secure the Bourguébus Ridge. Dempsey believed that if the operation were to succeed, his tanks would need to be on the ridge by the first afternoon and cancelled a second attack by heavy bombers scheduled for the first afternoon; although this was to be in direct support of the advance towards the ridge, he was concerned that the 11th Armoured Division should not be delayed waiting for the strike. Close air support for Goodwood would be provided by No. 83 Group RAF, to neutralise German positions on the flanks of VIII Corps, strong points such as the village of Cagny, attacking German gun and reserve positions and the interdiction of German troop movements. Each of the VIII Corps brigade headquarters, was allocated a Forward Air Control Post. German preparations The Germans considered the Caen area to be the foundation of their position in Normandy and were determined to maintain a defensive arc from the English Channel to the west bank of the Orne. On 15 July, German military intelligence warned Panzer Group West that from 17 July, a British attack out of the Orne bridgehead was likely. It was thought that the British would push south-east towards Paris. General Heinrich Eberbach, the commanding officer of Panzer Group West, designed a defensive plan, with its details worked out by his two corps and six divisional commanders. A belt of at least 10 miles (16 km) depth was constructed, organised into four defence lines. Villages within the belt were fortified and anti-tank guns placed along its southern and eastern edges. To allow tanks to move freely within the belt, the Germans decided not to establish anti-tank minefields between each defensive line. On 16 July, several reconnaissance flights were mounted over the British front but most of these were driven off by anti-aircraft fire. As dark fell, camera-equipped aircraft managed to bring back photographs taken by the light of flares, which revealed a one-way flow of traffic over the Orne into the British bridgehead. Later that day, a British Spitfire was shot down over German lines while photographing defences; British artillery and fighters attempted to destroy the crashed aircraft without success. LXXXVI Corps, reinforced by much artillery, held the front line. The 346th Infantry Division was dug in from the coast to the north of Touffreville and the depleted 16th Luftwaffe Field Division held the next section from Touffreville to Colombelles. Kampfgruppe von Luck, a battle group formed around the 21st Panzer Division 125th Panzergrenadier Regiment, was placed behind these forces with around 30 assault guns. The 21st Panzer Division armoured elements, reinforced with the 503rd Heavy Panzer Battalion, which included ten King Tigers, were north-east of Cagny in a position to support Luck's men and to act as a general reserve and the rest of the divisional panzergrenadiers, with towed anti-tank guns and assault guns, were dug in amongst the villages of the Caen plain. The 21st Panzer Division reconnaissance and pioneer battalions, were positioned on the Bourguébus Ridge to protect the corps artillery, which consisted of around 48 field and medium guns with an equal number of Nebelwerfer rocket launchers. The LXXXVI Corps had 194 artillery pieces, 272 Nebelwerfers and 78 anti-aircraft and anti-tank 88 mm guns. One battery of four 88 mm anti-aircraft guns from the 2nd Flak-Sturm Regiment, was positioned in Cagny, while in the villages along the Bourguébus Ridge there was a screen of 44 x 88 mm anti-tank guns from the 200th Tank Destroyer Battalion. Most of the LXXXVI Corps artillery was beyond the ridge covering the Caen–Falaise road.Facing Caen to the west of the Caen–Falaise road was the I SS Panzer Corps. On 14 July, elements of the 272nd Infantry Division took over the defence of Vaucelles from the 1st SS Division Leibstandarte SS Adolf Hitler, who moved into local reserve between the village of Ifs and the east bank of the Orne. The following day the 12th SS Panzer Division was placed in Oberkommando der Wehrmacht (OKW) reserve to rest and refit and—on Hitler's orders—to be in a position to meet a feared second Allied landing between the Orne and Seine rivers. The divisional artillery regiment and anti-aircraft battalion remained behind to support the 272nd Infantry Division and two battle groups were detached from the division. Kampfgruppe Waldmüller was moved close to Falaise and Kampfgruppe Wünsche to Lisieux, 40 kilometres (25 mi) east of Caen. Although Kampfgruppe Waldmüller was later ordered to rejoin the rest of the division at Lisieux, on 17 July Eberbach halted this move. Preliminary operations Operation Greenline Operation Greenline was launched by XII Corps during the evening of 15 July, with the 15th (Scottish) Infantry Division reinforced by a brigade of 53rd (Welsh) Infantry Division, the 34th Tank Brigade, 43rd (Wessex) Infantry Division and the 53rd (Welsh) Infantry Division, minus one brigade. Greenline was intended to convince the German command that the main British assault would be launched west of the Orne, through the positions held by XII Corps and to tie down the 9th and 10th SS Panzer divisions, so that they could not oppose Goodwood or Cobra. Supported by 450 guns, the British attack made use of artificial moonlight and started well despite disruption caused by German artillery fire. By dawn XII Corps had captured several of its objectives including the important height of Hill 113, although the much-contested Hill 112 remained in German hands. By committing the 9th SS Panzer Division, the Germans managed by the end of the day to largely restore their line, although a counter-attack against Hill 113 failed. Attacks next day by XII Corps gained no further ground and during the evening of 17 July, the operation was closed down and the British force on Hill 113 withdrawn. Operation Pomegranate Operation Pomegranate began on 16 July, in which XXX Corps was to capture several important villages. On the first day British infantry seized a key objective and took 300 prisoners but the next day there was much inconclusive fighting on the outskirts of Noyers-Bocage and Elements of the 9th SS Panzer Division were committed to the village defence. Although the British took control of the railway station and an area of high ground outside the village, Noyers-Bocage itself remained in German hands.The preliminary operations cost Second Army 3,500 casualties for no significant territorial gains but Greenline and Pomegranate were strategically successful. Reacting to the threats in the Odon Valley, the Germans retained the 2nd Panzer and 10th SS Panzer divisions in the front line and recalled the 9th SS Panzer Division from Corps reserve. The Germans suffered around 2,000 casualties. Terry Copp wrote that the fighting was "one of the bloodiest encounters of the campaign". During the late afternoon of 17 July, a patrolling Spitfire spotted a German staff car on the road near the village of Sainte-Foy-de-Montgommery. The fighter made a strafing attack driving the car off the road. Among its occupants was Field Marshal Erwin Rommel, the commander of Army Group B, who was seriously wounded, leaving Army Group B temporarily leaderless. Battle 18 July Shortly before dawn on 18 July, the Highland infantry in the south of the Orne bridgehead, quietly retired 0.5 mi (0.80 km) from the front line. At 05:45, 1,056 Handley Page Halifax and Avro Lancaster heavy bombers flying at 3,000 ft (910 m) dropped 4,800 long tons (4,900 t) of high explosive bombs around Colombelles, the steelworks, on the positions of the 21st Panzer Division and on the village of Cagny, reducing half of it to rubble. At 06:40 the British artillery opened fire and twenty minutes later, the second wave of bombers arrived. From 10,000–13,000 ft (3,000–4,000 m), American B-26 Marauders released 563 long tons (572 t) of fragmentation bombs on the 16th Luftwaffe Field Division, as fighter-bombers attacked German strong points and gun positions. During the 45-minute bombardment, the troops and tanks of the 11th Armoured Division moved out of their concentration areas towards the start line. H Hour was set for 07:45 and on schedule, the artillery switched to a creeping barrage, which moved ahead of the 11th Armoured Division. As the division moved off, more artillery opened fire on Cuverville, Demouville, Giberville, Liberville, Cagny and Émiéville and dropped harassing fire on targets as far south as Garcelles-Secqueville and Secqueville la Campagne. Fifteen minutes later, American heavy bombers dropped 1,340 long tons (1,360 t) of fragmentation bombs in the Troarn area and on the main German gun line on the Bourguébus Ridge. Only 25 bombers in the three waves were lost, all to German anti aircraft fire. Aerial support for the operation was then handed over to 800 fighter-bombers of 83 and 84 Groups.The bombing put the 22nd Panzer Regiment and the III Company, 503rd Heavy Panzer Battalion temporarily out of action, causing varying degrees of damage to their tanks. Some were overturned, some were destroyed and twenty were later found abandoned in bomb craters. Most of the German front line positions had been neutralised, with the survivors left "dazed and incoherent". Dust and smoke had impaired the ability of the bomber crews to identify all their targets and others on the periphery of the bombing zones had remained untouched. Cagny and Émiéville were extensively bombed but most of the defenders were unscathed and recovered in time to meet the British advance—both places having clear lines of fire, on the route the British were to take. The 503rd Heavy Tank Battalion rallied rapidly and got to work digging out their tanks. On the Bourguébus Ridge, a number of guns were destroyed by the bombing but most of the artillery and anti-tank guns remained intact. By 08:05, the 2nd Fife and Forfar Yeomanry and the 3rd Royal Tank Regiment of the 29th Armoured Brigade, had navigated minefields, to reach the Caen–Troarn railway line. The first phase of the rolling barrage ended at 08:30, by which time large numbers of prisoners from the 16th Luftwaffe Division had been rounded up. By the time the artillery resumed firing at 08:50, only the first armoured regiment and a portion of the second had crossed the line. Although opposition was still minimal and more prisoners were taken, the two regiments struggled to keep up with the barrage and were moving out of supporting range of their reserves. On schedule at 09:00 the barrage lifted and 35 minutes later, the lead squadrons reached the Caen–Vimont railway. In reserve, the 23rd Hussars had managed to clear the first railway line only to become embroiled in a 1+1⁄2-hour engagement with a battery of self-propelled guns of the 200th Assault Gun Battalion, that had been mistaken for Tiger tanks. As the 2nd Fife and Forfar Yeomanry advanced past Cagny, they were engaged by anti-tank guns in Cagny to the east. Within a few minutes at least twelve tanks were disabled. The Yeomanry pressed their advance south and were engaged by the main German gun line on the ridge, while the 3rd Royal Tank Regiment having shifted westward and exchanged fire with the German garrison in Grentheville, before moving around the village and advancing along the southern outskirts of Caen, towards Bras and Hubert-Folie. What had been conceived as an attack towards the Bourguébus Ridge by three armoured divisions, had become an unsupported advance by two tank regiments, out of sight of one other, against heavy German fire. By 11:15, the British reached the ridge and the villages of Bras and Bourguébus. Some losses were inflicted on the German tanks but attempts to advance further were met by determined opposition, including fire from the rear from pockets of resistance that had been bypassed.General Eberbach ordered a counter-attack, "not a defensive move but a full armoured charge". The 1st SS Panzer Division was to attack across the ridge, while in the Cagny area the 21st Panzer Division was to recover all lost ground. German tanks started to arrive on the ridge around noon and the British tank crews were soon reporting German tanks and guns everywhere. Hawker Typhoon fighter-bombers carrying RP-3 rockets were directed onto the ridge throughout the afternoon, delaying and eventually breaking up the 1st SS Panzer Division counter-attack. A final attempt to storm the ridge resulted in the loss of 16 British tanks and a small counter-attack during the afternoon was driven off, with the destruction of six German Panthers.Just before 10:00, the Guards Armoured Division caught up with the 11th Armoured Division and pressed on towards Cagny. By 12:00 the leading elements were halted, engaged in fighting. A German counter-attack against the 2nd Armoured Grenadier Guards by 19 tanks from the 21st Panzer Division and the Tigers of the 503rd Heavy Panzer Battalion, failed when the German tanks came under fire from their own guns and two Tigers were knocked out. An isolated Tiger II (King Tiger) attempting to manoeuvre out of danger, was caught by an Irish Guards Sherman tank that had also become detached from its unit. The Sherman crew fired into the Tiger and then rammed it; anti-tank fire from other British units then penetrated the Tiger's armour. Both crews abandoned their vehicles and most of the German crew was captured. The 503rd Heavy Panzer Battalion later attacked the Coldstream Guards but was forced to withdraw by massed anti-tank fire. It took the Guards the rest of the day to capture Cagny, which was found abandoned when infantry entered the village. Attempts to renew the advance were met by fierce German resistance. Starting last, the only element of the 7th Armoured Division to enter the battle was the 5th Royal Tank Regiment (5th RTR). At 17:00 near Cuverville it knocked out two Panzer IVs for the loss of four tanks and then cleared Grentheville which had been bypassed earlier in the day by the 3rd RTR and several prisoners were taken. A German counter-attack by six tanks petered out after two tanks each were destroyed. The 11th Armoured Division pulled back to the Caen–Vimont railway line for the evening and replacement tanks were brought forward for all divisions, with the 11th Armoured receiving priority. German recovery teams went forward to recover and repair as many of their tanks as possible, as few replacements were available. Unnoticed by the British, a gap had been created between Emièville and Troan. This was closed during the night by the 12th SS Panzer Division, which had lost ten tanks, en route, to air attacks. A number of minor German counter-attacks were launched from the ridge; one at dusk was broken up by British artillery and anti-tank fire, which destroyed a Panther and Tiger, another after dark led by a captured Sherman as a ruse, was repulsed after the Sherman and two Panthers were knocked out by a British anti-tank battery. During the night, German bombers dropped flares over the Orne bridges, which then came under aerial attack. One bridge was slightly damaged and the headquarters of the 11th Armoured Division was hit, as were some tank crews who had survived the fighting.In their fighting around Cagny, the Guards Armoured Division lost fifteen tanks destroyed and 45 tanks damaged. The 11th Armoured Division lost 126 tanks, although only forty were write-offs; the rest were damaged or had broken down. (The loss of 126 tanks of the 219–244 tanks that crossed the start line has been a common feature of accounts of Goodwood but the divisional commander, the VIII Corps historian and Chester Wilmot gave 126 tank losses. Michael Reynolds gave "...at least 125" and Christopher Dunphie 128 losses.) The armoured divisions suffered 521 casualties during the day, Guards Armoured Division suffered 127 casualties, the 7th Armoured Division had 48 casualties and the 11th Armoured Division had 336 casualties. On the eastern flank, the 3rd Infantry Division had a successful day, capturing all of its objectives except for Troarn. Operation Atlantic On the Canadian front, Operation Atlantic began at 08:15, with a rolling barrage and infantry and tanks crossed their start line twenty minutes later. At 08:40, British infantry from the 159th Infantry Brigade entered Cuverville; the village and its surrounding area were secured by 10:30 but patrols found Demouville firmly held and attempts to capture this second objective were delayed while the infantry reorganised. The rest of the day saw a slow southward advance, as numerous German positions were cleared. Linking up with their armoured support by nightfall, the infantry dug in around le Mesnil-Frèmentel. 19–20 July The German armour counter-attacked late in the afternoon and fighting continued along the high ground and around Hubert-Folie on 19 July and 20 July, bringing the attack to a halt. On 21 July, Dempsey started to secure his gains by substituting infantry for armour. Aftermath Analysis Tactically, the Germans contained the offensive, holding many of their main positions and preventing an Allied breakthrough, but they had been startled by the weight of the attack and preliminary aerial bombardment. It was clear that any defensive system less than 5 mi (8.0 km) deep could be overwhelmed at a stroke and the Germans could afford to man their defences in such depth only in the sector south of Caen. Goodwood resulted in the British extending the front line by 7 mi (11 km) to the east of Caen, with the penetration being as much as 12,000 yards (11 km; 6.8 mi) in some places; the southern suburbs of Caen were captured by the Canadians during Operation Atlantic.The attack reinforced the German view that the greatest danger was on the eastern flank. As German armoured reinforcements arrived in Normandy, they were drawn into defensive battles in the east and worn down. By the end of July only one and a half panzer divisions were facing American forces at the western end of the front, compared with six and a half facing the British and Canadians at the eastern end of the bridgehead. The German defence of Normandy was close to collapse when Operation Cobra breached the thin German defensive 'crust' in the west and few German mechanised units were available to counter-attack. Martin Blumenson, the American official historian, wrote after the war that had Goodwood created a breakthrough, "... Cobra would probably have been unnecessary". Goodwood inflicted substantial losses on the German defenders but not a shattering blow. The effect on the morale of the German commanders was greater and added to the loss of Rommel, who was wounded in an RAF air attack. Kluge lost his early optimism on being appointed to replace Rundstedt and wrote to Hitler on 21 July predicting an imminent collapse.Operation Goodwood was launched at a time of great frustration in the higher command of the Allies, which contributed to the controversy surrounding the operation. The Allied bridgehead was about 20 percent of the planned size, which led to congestion and some fear of a stalemate. Allied commanders had not been able to exploit their potentially decisive advantages in mobility during June and early July 1944. Much of the controversy surrounding the objectives of the battle originates from the conflicting messages given by Montgomery. He talked up the objectives of Goodwood to the press on the first day, later saying that this was propaganda to encourage the Germans to keep powerful units at the east end of the battlefield.In the planning of Goodwood, Montgomery appeared to promise that the attack would be a breakthrough and that when the VIII Corps failed to break-out, by some accounts the Supreme Commander, US General Dwight D. Eisenhower, felt he had been misled. While his intermittent communications to Supreme Headquarters Allied Expeditionary Force (SHAEF) appeared to promise a breakthrough, Montgomery was writing orders to his subordinates for a limited attack. Copies of orders forwarded to SHAEF called for an armoured division to take Falaise, a town far in the German rear. Three days prior to the attack, Montgomery revised the orders, eliminating Falaise as an objective but neglected to forward copies of the revision; Eisenhower was later furious at the result, which dogged Montgomery, as it allowed his detractors, especially Air Marshal Arthur Tedder, to imply that the operation was a failure.Stephen Biddle wrote that Goodwood was a significant tactical setback for Montgomery. Despite having preponderant force and air superiority, British progress was slow and ultimately failed to break through. Montgomery chose an unusually narrow spearhead of just 2 km (1.2 mi), which created a congested line of advance. British infantry was lacking in suitable junior officers and non-commissioned officers, which inhibited small-unit tactics. In Biddle's analysis, The British systematically failed to coordinate movement and suppressive fires after about mid-morning of the opening day.... The attack had by then moved beyond the reach of the British batteries on the northern side of the Orne River and the congestion in the march columns had kept the artillery from moving forward into supporting range.... The net result was thus an exposed, massed, nearly pure-tank assault pressing forward rapidly without supporting infantry or supporting suppressive fires. The Germans, by contrast, made great efforts to conceal their forces—moving under cover of dark, off the main roads, in small units and under radio silence. Casualties Simon Trew wrote that "the first estimates of Allied losses for Operation Goodwood appeared horrific, that Second Army had lost 4,011 men... ." In 2006, G. S. Jackson gave casualties in the armoured divisions from 18 to 19 July of 1,020 men. In 2001, Michael Reynolds quoted the 21st Army Group war diary of casualties in I and VIII Corps of 3,474 men. Operation Atlantic cost the Canadians from 1,349 to 1,965 casualties. Colonel Charles Stacey, the Canadian official historian, gave casualties of all Canadian units in Europe, for the four days' fighting of 1,965 in all categories; 441 men were killed or died of wounds. Simon Trew wrote that "no conclusive assessment can ever be made" in regards to the losses of both sides. In 2014, John Buckley gave a figure of 5,500 casualties during Goodwood and Atlantic.Over 2,000 German prisoners were taken and c. 100 tanks were destroyed. Jackson also wrote of c. 100 German tank losses. In the official history Major Lionel Ellis wrote that the 1st SS and 21st Panzer divisions lost 109 tanks on the first day of the battle. Reynolds recorded 77 German tanks or assault guns knocked out or damaged during the operation and that the claim of 75 tanks or assault guns destroyed—as stated in a post-war interview, by the commanding officer of the 11th Armoured Division, for a British staff college training film on the operation—"can be accepted as accurate". Michael Tamelander wrote in 2004 that Panzergruppe West recorded the loss of 75 tanks during the period from 16 to 21 July.British tank losses during Goodwood have been debated, with the loss ranging from 218 to 500. In addition to VIII Corps losses, about twenty tanks were lost in the flanking operations. Reynolds wrote that study of the records suggests that the maximum number of tanks lost during Operation Goodwood was 253, most of which were damaged rather than write-offs. Tamelander and Niklas Zetterling wrote that during Goodwood 469 tanks were lost by the armoured divisions (including 131 tanks on 19 July and 68 on 20 July) but that the majority could be repaired. Trew rejected those figures and wrote that after much investigation, VIII Corps losses amounted to 197 tanks on 18 July, 99 tanks on 19 July and 18 tanks on 20 July, "for a total of 314, of which 130 were completely destroyed". Trew wrote that "the tank strength returns for VIII Corps 18–21 July show a loss of 218 tanks (that could not be repaired or immediately replaced), including 145 tanks from 11th Armoured Division". In 2014 John Buckley wrote that 400 British tanks were knocked out and that many were recovered and put back into service, although the morale of some of the crews deteriorated. Notes Footnotes References Further reading External links Morss, R. "59th (Staffordshire) Division in WWII: Operation Pomegranate". Retrieved 18 May 2014. Zetterling: data on German losses in Normandy RAF photograph of Sannerville and Banneville la Campagne after the morning raid of 18 July 1944	different from	{ "answer_start": [ 0 ], "text": [ "Operation Goodwood" ] }
The UC San Diego Tritons are the athletic teams that represent the University of California, San Diego. UC San Diego has 23 varsity sports teams, as well as esports teams, and offers student participation in a wide range of sports. As of July 1, 2020, all UC San Diego teams participate at the NCAA Division I (DI) level in the Big West Conference. During their time in NCAA Division II and the California Collegiate Athletic Association starting in the 2000–01 season, UC San Diego placed in the top 5 in the Division II NACDA Directors' Cup standings nine times, including three 2nd-place finishes. NCSA Athletic Recruiting ranked the Tritons as the nation's top Division II program for eight consecutive years.In May 2016, UC San Diego students voted to transition all sports teams to the NCAA Division I level. On November 27, 2017, it was announced that UC San Diego would begin the transition to NCAA Division I and join the Big West Conference on July 1, 2020. History Move to Division I In 2010, UC San Diego considered elevating its athletics to NCAA Division I for all sports. They were looking to join the Big West Conference. However, there were several problems. After the Big West added the University of Hawaii in 2010, they would have 10 teams, meaning any extra member would require more conference games in basketball, upsetting the current schedule balance. In addition, in order to meet the minimum Division I scholarship requirements, the student body would need to vote for a fee increase sometime during the 2011–2012 academic year. After the Big West elected not to invite UC San Diego in May 2011, plans were put on hold and UC San Diego remained a Division II team. However, a student-led movement resulted in a vote on a fee increase for UC San Diego students in the hopes to enhance the school's chances of becoming a Division I school. In March 2012, the UC San Diego student body rejected an increase in activity fees to support the move to Division I. The vote fell 11,407 to 6,470 (51% of the student body voted). In January 2016, Associated Students UC San Diego unanimously approved the wording of a new Division I referendum. In May, UC San Diego undergraduates voted to increase athletic fees by $480 per year and transition UC San Diego athletics to Division I. The fee increase will fund the athletic scholarships required for NCAA Division I schools. The move was approved by the UC San Diego Academic Senate in December 2016. UC San Diego's move remains contingent upon an invitation to join the Big West Conference.In a separate move by the Big West Conference to sponsor men's volleyball, Big West teams from the MPSF split to join their own conference that includes UC San Diego as an affiliate member starting in the 2017–18 school year (2018 season). The Tritons' joining the Big West as an affiliate for men's volleyball was not an indicator that the Tritons would be accepted as a full member yet since UC San Diego had long played the sport in the MPSF at a Division I level and was part of the original coalition talks with the Big West to split from MPSF men's volleyball. Early in April 2017, the San Diego Tribune reported that the Big West had rejected UC San Diego's application to join the conference. The Big West commission overseeing new members into the conference consists of the Presidents and Chancellors of every member school. There has not been a formal public confirmation of the rejection, but UC San Diego may still attempt to make moves to join the Big West or another conference (such as the Western Athletic Conference) until its 2018 deadline set by the referendum. However, on November 27, 2017, UC San Diego was accepted and officially started the journey towards the Big West conference along with Cal State Bakersfield. UC San Diego's women's water polo team joined the Big West in 2019, and UC San Diego began the required four year transition period on July 1, 2020 to be a full member on July 1, 2024. Sports sponsored A member of the Big West Conference, UC San Diego sponsors teams in ten men's, eleven women's, and one coed NCAA sanctioned sports. The school also sponsors a varsity men's rowing team, but men's rowing is not sanctioned by the NCAA. The rowing teams are members of the Western Intercollegiate Rowing Association. The men's water polo team is a member of the Western Water Polo Association. The fencing team is a member of the Intercollegiate Fencing Conference of Southern California. Men's volleyball and women's water polo both compete in the Big West Conference, with the former joining that league in 2017 and the latter in 2019, ahead of the school becoming a full member of the Big West on July 1, 2020 and beginning the transition to Division I. From Fall 2000 to Spring 2017, UC San Diego teams competed primarily in the California Collegiate Athletic Association. The school was awarded the Hiegert Commissioner's Trophy (awarded to the CCAA school with the highest aggregate ranking in eight sports) seven times—five consecutive years from 2006–2010 and again in 2016 and 2017. National champions are highlighted in bold and italicized. Baseball The UC San Diego Tritons baseball team is the varsity intercollegiate baseball team of the University of California, San Diego. The team plays its home games at Triton Ballpark. Basketball Men's basketball The UC San Diego Tritons men's basketball team represents the University of California, San Diego. The team plays its home games at RIMAC Arena. Women's basketball The UC San Diego women's basketball team plays its home games at RIMAC Arena. It has won the CCAA five times, during the 2006–07, 2008–09, 2009–10, 2012–13, and 2016–17 seasons. The Tritons advanced to the NCAA West Regional 1st Round in 2003–04, 2005–06, and 2009–10, and reached the 2nd Round in 2007–08 and 2008–09. They were the NCAA West Region runners-up in 2011–12 and 2015–16. In 2006–07, they reached the NCAA Final Four. Fencing The UC San Diego men's and women's fencing squads compete at Main Gym and RIMAC Arena. They competed in the Intercollegiate Fencing Conference of Southern California at the NCAA Division I level. The Tritons won this league's championship every year between 2005 and 2016. Under former Head Coach, Heidi Runyan, at least one Triton has qualified for the NCAA Division I Championships annually since 2005. The highest NCAA finish the Tritons have garnered was 13th in 2008 when six qualified to compete. In 2018, the men's and women's squads finished 14th in the NCAA circuit after sending five fencers to Penn State in State College, Pennsylvania where the competition was held. The team hosts the Annual BladeRunner Regional Open Circuit tournament as part of the United States Fencing Association. Rowing The UC San Diego rowing team was established in 1966 and practices on Mission Bay, roughly 10 miles from the main university campus. The rowing team is centered out of the Coggeshall Rowing Center on El Carmel Point in Mission Bay which houses the San Diego Rowing Club, the University of San Diego collegiate rowing program, and the UC San Diego collegiate rowing program. Men's rowing The Tritons are members of the Western Sprints Conference within the Intercollegiate Rowing Association. The Western Sprints conference has two automatic qualification positions for the IRA National Championship Regatta. The Tritons also have historic association with the Western Intercollegiate Rowing Association (WIRA) conference prior to the establishment of the Western Sprints Regatta. The Tritons have made six appearances at the National Championship, having first qualified in 2009. The next appearances were in 2011, 2013, 2017, 2018, and 2019 with the 2017–2019 seasons having been the only consecutive appearances in program history. Having never been nationally ranked prior to the 2007 season, UC San Diego has now spent time ranked in the top 25 of the U.S. Rowing Collegiate Poll in six of the last 11 seasons going into the 2020 season.The Western Sprints conference includes UC San Diego, University of San Diego, Santa Clara University, and Gonzaga University. The Tritons secured a conference championship with a sweep of the event in both 2018 and 2019 with the Varsity 8, Junior Varsity 8, and Third Varsity 8 enjoying a first place finish. UC San Diego has also enjoyed success at the WIRA Championship: a regional championship that takes places on Lake Natoma in Folsom, California. At WIRA's, the Triton's have always secured a position on the podium. The Tritons won the overall team championship in 2006, 2011, and 2019, including a monumental sweep of the Varsity 8, Second Varsity 8, and Third Varsity 8 races in 2019. Following the sweep, Zach Johnson, the head coach at the time, was named WIRA Coach of the Year. Women's rowing The Triton Women's team is a part of the NCAA Division I. On March 26, 2021, UC San Diego and the Colonial Athletic Association jointly announced that the Triton's women's rowing team had joined the conference effective immediately. Soccer Men's soccer The UC San Diego men's soccer team hosts its opponents at the Triton Soccer Stadium at RIMAC Field. In 2003, 2013, and 2014, it advanced to the first round of the NCAA West Regional. In 2013, they were the CCAA tournament runners-up. The best season in team history occurred in 2016, when the team advanced to the NCAA Division II Semifinals after claiming the CCAA league championship, CCAA tournament championship, and the NCAA West Region title. Women's soccer The UC San Diego women's soccer team plays its home matches at the Triton Soccer Stadium at RIMAC Field. In its first two seasons of Division II play, 2000 and 2001, the team was crowned CCAA Champions and NCAA National Champions. The Tritons again won the CCAA in 2002, 2003, 2005, 2006, 2008, 2011, 2012, 2015, 2016, and 2017, reaching the NCAA Final Four in 2003 and 2017 and being named NCAA Runners-Up in 2010 and 2012. They reached the NCAA West Regional 2nd Round in 2005, 2008, and 2009 and were named the regional runners-up in 2016, but were eliminated in the first round in 2002, 2007, 2011, and 2015. Since its promotion to Division II in 2000, the team has failed to reach the NCAA playoffs only three times, in 2004, 2013, and 2014, and has posted an undefeated CCAA record once, going 12–0 in league play and winning the tournament and division in 2016. Softball The UC San Diego softball team plays its home games at Triton Softball Stadium, adjacent to RIMAC Arena. The Tritons advanced to the NCAA West Regionals in 2001, 2002, 2007, 2008, 2009. 2011, 2012, 2013, and 2014. In 2011, they were the NCAA National Champions, having won the NCAA West Region and the CCAA. In 2012, they won the CCAA tournament and repeated as NCAA West Region Champions, and were eventually crowned the NCAA National Runners-Up. They won their second CCAA tournament in 2016. Swimming Men's Swimming The UC San Diego men's swim team competes in the Mountain Pacific Sports Federation, practicing and competing at the Canyonview Aquatic Center. Since joining Division I prior to the 2021-22 season, the Tritons have finished 4th and 5th in the 2022 and 2023 MPSF Championships, respectively. In 2022, Senior Ivan Kurakin won the 200 yard freestyle, while Freshman Aidan Simpson won the 200 yard breaststroke. Women's Swimming The UC San Diego women's swim team competes in the Mountain Pacific Sports Federation, practicing and competing at the Canyonview Aquatic Center. In 2022, their first year as a Division I program, the Triton women upset the then 5-time defending champions Hawaii to win the MPSF Championships, their first Conference Championship in any program since joining Division I. Fueled by 2 wins from Junior Katja Pavicevic (200 IM, 200 Breaststroke), as well as individual wins from Julissa Arzave (1650 Freestyle), Ciara Franke (200 Freestyle), and Tina Reuter (400 IM), and multiple relay victories, the Tritons edged out Hawaii by a meager 12.5 points.In 2023, the Tritons were unable to repeat as champions, finishing second behind Hawaii. Tennis Men's tennis The UC San Diego men's tennis team competes in the Intercollegiate Tennis Association and plays its home games at the Northview Tennis Courts. The team advanced to the NCAA Division II National Championships each year between 2001 and 2007, and returned there in 2010, 2011, 2013, and 2014. The team's best finish at the NCAA tournament came in 2007, when it was eliminated in the Final Four. Women's tennis The UC San Diego women's tennis team competes in the Intercollegiate Tennis Association and plays its home matches at the Northview Tennis Courts. They were undefeated CCAA champions every season between 2004 and 2009, advancing to the NCAA West Regional each year. They again won the CCAA in 2010, advancing to the regional championship with a 9–1 conference record. Volleyball Men's volleyball (Division I) The UC San Diego men's volleyball team competes in the Big West Conference, having joined from the Mountain Pacific Sports Federation for the 2018 season (2017–18 school year). The team's home matches against its Division I opponents are played at RIMAC Arena. The program's best finish in the new millennium came in 2009, when the team ended the season ranked ninth in the MPSF. Women's volleyball The UC San Diego women's volleyball team plays its home matches at RIMAC Arena. The program has made the postseason every year except 2005 and 2014 as well as the NCAA West Regional every year except 2005, 2014, 2015, and 2017. In 2001, the Tritons reached the NCAA Division II Final Four. The team won the CCAA regular season in 2004 with an undefeated league record. Water Polo Men's water polo The UC San Diego men's water polo team competes in the Western Water Polo Association against Division I opponents. They host their opponents at Canyonview Aquatic Center in Warren College. The Tritons have reached the NCAA Final Four in 1995, 1998, 1999, 2000, 2006, 2011, 2014, and 2015. They were the NCAA National Runners-Up in 2000. Women's water polo The UC San Diego women's water polo team competes in the Big West Conference against Division I opponents. They host their opponents at Canyonview Aquatic Center in Warren College. Esports UC San Diego has fielded multiple esports teams in a variety of games, both for team play and individual competition. Most notably the Splatoon team, Triton Splatoon, competed in the playoffs of two of the Twitch streamed Proton Splat Leagues for Splatoon 2, taking 4th place in season 4 after being defeated in the first round and going on an impressive run through the losers bracket, and 1st in season 6 after a close 11 game match across two best of 7 sets against team New Horizon in a rematch from their semifinals match. Former varsity sports Football UC San Diego has not fielded a football team except in Fall 1968 when a newly formed pigskin organization turned in a winless season and then folded for lack of interest. Since then, the subject of bringing NCAA football back to UC San Diego has been a recurring topic. Tom Ham, a local restaurateur and a supporter of UC San Diego football since the 1960s, has said that UC San Diego would have no future in San Diego without "big-time" football. Proponents of a major football team have projected benefits that include greater school spirit and a more well-rounded school experience for students as well as enhancing the school's national profile. Opposition to "big-time" football comes from a wide range of school faculty and administrators such Daniel Wulbert, Revelle College provost, who says that any boost to school spirit wouldn't be worth the sacrifice, and that he wants UC San Diego to "have a life for reasons other than watching hired athletes come and play." Both sides acknowledge that adding an 80- to 100-man football team would not only cost some US$1–1.5M annually, but that the initial outlay in equipment and facilities would be in the tens of millions. Furthermore, in order to comply with Title IX's requirement for equal sports opportunities for both sexes, some three women's teams (80–100 athletes) would have to be added, or three existing men's teams disbanded. Without the expense of football, UC San Diego has been characterized as having "the best all-around program, with the most success by the most student-athletes" in San Diego. Championships Appearances The UC San Diego Tritons competed in the NCAA Tournament across 20 active sports (1 co-ed, 9 men's, and 10 women's) 222 times at the Division II level. Baseball (11): 2007, 2008, 2009, 2010, 2011, 2012, 2014, 2015, 2017, 2018, 2019 Men's basketball (5): 2008, 2016, 2017, 2018, 2019 Women's basketball (12): 2004, 2006, 2007, 2008, 2009, 2010, 2012, 2013, 2016, 2017, 2018, 2019 Men's cross country (4): 2001, 2003, 2007, 2019 Women's cross country (7): 2002, 2003, 2004, 2005, 2006, 2007, 2014 Fencing (24): 1994, 1995, 1997, 1998, 1999, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019 Men's golf (2): 2004, 2019 Men's soccer (5): 2003, 2013, 2014, 2016, 2019 Women's Rowing (5): 2006, 2007, 2008, 2017, 2019 Women's soccer (17): 2000, 2001, 2002, 2003, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2015, 2016, 2017, 2018, 2019 Softball (11): 2002, 2007, 2008, 2009, 2011, 2012, 2013, 2014, 2016, 2018, 2019 Men's swimming and diving (19): 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019 Women's swimming and diving (19): 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019 Men's tennis (16): 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2013, 2014, 2016, 2017, 2018 Women's tennis (12): 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2016, 2018 Men's outdoor track and field (13): 2001, 2002, 2005, 2006, 2008, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2018 Women's outdoor track and field (14): 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2014, 2017 Women's volleyball (15): 2000, 2001, 2002, 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2015, 2019 Men's water polo (16): 1989, 1991, 1992, 1993, 1995, 1998, 1999, 2000, 2002, 2006, 2011, 2013, 2014, 2015, 2018, 2019 Women's water polo (8): 2011, 2013, 2014, 2015, 2016, 2017, 2018, 2019Men's Rowing is not governed by the NCAA but instead by the Intercollegiate Rowing Association (IRA). The Tritons have represented the University at the IRA National Championships six times. Men's Rowing (6): 2009, 2011, 2013, 2017, 2018, 2019 Team The Tritons of UC San Diego earned 3 NCAA championships at the Division II level. Women's (3) Soccer (2): 2000, 2001 Softball (1): 2011Results UC San Diego won 20 national championships at the NCAA Division III level. Men's golf: 1993 Men's soccer: 1988, 1991, 1993 Women's soccer: 1989, 1995, 1996, 1997, 1999 Women's tennis: 1985, 1987, 1989 Women's volleyball: 1981, 1984, 1986, 1987, 1988, 1990, 1997Below are twenty-four national club team championships: Co-ed badminton (4): 2001, 2003, 2005, 2006 (ABA) Men's badminton (3): 2003, 2005, 2006 (ABA) Women's badminton (4): 2001, 2003, 2005, 2006 (ABA) Men's rugby – Division II (2): 1998, 1999 (USA Rugby) Co-ed surfing (7): 1970, 1983, 1990, 1993, 1995, 1997, 2003 (NCSA) Women's triathlon (2): 2008, 2009 (USA Triathlon) Women's ultimate (2): 2002, 2019 (USA Ultimate) Co-ed water skiing – Division II (1): 2004 (NCWSA)Note: Those with no denoted division is assumed that the institution earned a national championship at the highest level. Individual UC San Diego had 47 Tritons win NCAA individual championships at the Division II level. At the NCAA Division III level, UC San Diego won 84 individual championships. Traditions Boosters UC San Diego recognizes two external organizations of athletic boosters: the Triton Athletic Associates is a booster group of parents, alumni, and friends who have each donated between US$50 and $2,500; and the UC San Diego Athletic Board is made up of donors who have given US$10,000 or more to athletic programs. On campus, spirit and support groups consist of the UC San Diego Pep Band, Triton Tide (a student engagement group), the UC San Diego Cheerleaders, and the UC San Diego Dance Team. Further opportunities for athletic involvement are available to students interested in team staffing and management. Mascot King Triton appears as a costumed character mascot. References External links Official website	league	{ "answer_start": [ 294 ], "text": [ "NCAA Division I" ] }
The UC San Diego Tritons are the athletic teams that represent the University of California, San Diego. UC San Diego has 23 varsity sports teams, as well as esports teams, and offers student participation in a wide range of sports. As of July 1, 2020, all UC San Diego teams participate at the NCAA Division I (DI) level in the Big West Conference. During their time in NCAA Division II and the California Collegiate Athletic Association starting in the 2000–01 season, UC San Diego placed in the top 5 in the Division II NACDA Directors' Cup standings nine times, including three 2nd-place finishes. NCSA Athletic Recruiting ranked the Tritons as the nation's top Division II program for eight consecutive years.In May 2016, UC San Diego students voted to transition all sports teams to the NCAA Division I level. On November 27, 2017, it was announced that UC San Diego would begin the transition to NCAA Division I and join the Big West Conference on July 1, 2020. History Move to Division I In 2010, UC San Diego considered elevating its athletics to NCAA Division I for all sports. They were looking to join the Big West Conference. However, there were several problems. After the Big West added the University of Hawaii in 2010, they would have 10 teams, meaning any extra member would require more conference games in basketball, upsetting the current schedule balance. In addition, in order to meet the minimum Division I scholarship requirements, the student body would need to vote for a fee increase sometime during the 2011–2012 academic year. After the Big West elected not to invite UC San Diego in May 2011, plans were put on hold and UC San Diego remained a Division II team. However, a student-led movement resulted in a vote on a fee increase for UC San Diego students in the hopes to enhance the school's chances of becoming a Division I school. In March 2012, the UC San Diego student body rejected an increase in activity fees to support the move to Division I. The vote fell 11,407 to 6,470 (51% of the student body voted). In January 2016, Associated Students UC San Diego unanimously approved the wording of a new Division I referendum. In May, UC San Diego undergraduates voted to increase athletic fees by $480 per year and transition UC San Diego athletics to Division I. The fee increase will fund the athletic scholarships required for NCAA Division I schools. The move was approved by the UC San Diego Academic Senate in December 2016. UC San Diego's move remains contingent upon an invitation to join the Big West Conference.In a separate move by the Big West Conference to sponsor men's volleyball, Big West teams from the MPSF split to join their own conference that includes UC San Diego as an affiliate member starting in the 2017–18 school year (2018 season). The Tritons' joining the Big West as an affiliate for men's volleyball was not an indicator that the Tritons would be accepted as a full member yet since UC San Diego had long played the sport in the MPSF at a Division I level and was part of the original coalition talks with the Big West to split from MPSF men's volleyball. Early in April 2017, the San Diego Tribune reported that the Big West had rejected UC San Diego's application to join the conference. The Big West commission overseeing new members into the conference consists of the Presidents and Chancellors of every member school. There has not been a formal public confirmation of the rejection, but UC San Diego may still attempt to make moves to join the Big West or another conference (such as the Western Athletic Conference) until its 2018 deadline set by the referendum. However, on November 27, 2017, UC San Diego was accepted and officially started the journey towards the Big West conference along with Cal State Bakersfield. UC San Diego's women's water polo team joined the Big West in 2019, and UC San Diego began the required four year transition period on July 1, 2020 to be a full member on July 1, 2024. Sports sponsored A member of the Big West Conference, UC San Diego sponsors teams in ten men's, eleven women's, and one coed NCAA sanctioned sports. The school also sponsors a varsity men's rowing team, but men's rowing is not sanctioned by the NCAA. The rowing teams are members of the Western Intercollegiate Rowing Association. The men's water polo team is a member of the Western Water Polo Association. The fencing team is a member of the Intercollegiate Fencing Conference of Southern California. Men's volleyball and women's water polo both compete in the Big West Conference, with the former joining that league in 2017 and the latter in 2019, ahead of the school becoming a full member of the Big West on July 1, 2020 and beginning the transition to Division I. From Fall 2000 to Spring 2017, UC San Diego teams competed primarily in the California Collegiate Athletic Association. The school was awarded the Hiegert Commissioner's Trophy (awarded to the CCAA school with the highest aggregate ranking in eight sports) seven times—five consecutive years from 2006–2010 and again in 2016 and 2017. National champions are highlighted in bold and italicized. Baseball The UC San Diego Tritons baseball team is the varsity intercollegiate baseball team of the University of California, San Diego. The team plays its home games at Triton Ballpark. Basketball Men's basketball The UC San Diego Tritons men's basketball team represents the University of California, San Diego. The team plays its home games at RIMAC Arena. Women's basketball The UC San Diego women's basketball team plays its home games at RIMAC Arena. It has won the CCAA five times, during the 2006–07, 2008–09, 2009–10, 2012–13, and 2016–17 seasons. The Tritons advanced to the NCAA West Regional 1st Round in 2003–04, 2005–06, and 2009–10, and reached the 2nd Round in 2007–08 and 2008–09. They were the NCAA West Region runners-up in 2011–12 and 2015–16. In 2006–07, they reached the NCAA Final Four. Fencing The UC San Diego men's and women's fencing squads compete at Main Gym and RIMAC Arena. They competed in the Intercollegiate Fencing Conference of Southern California at the NCAA Division I level. The Tritons won this league's championship every year between 2005 and 2016. Under former Head Coach, Heidi Runyan, at least one Triton has qualified for the NCAA Division I Championships annually since 2005. The highest NCAA finish the Tritons have garnered was 13th in 2008 when six qualified to compete. In 2018, the men's and women's squads finished 14th in the NCAA circuit after sending five fencers to Penn State in State College, Pennsylvania where the competition was held. The team hosts the Annual BladeRunner Regional Open Circuit tournament as part of the United States Fencing Association. Rowing The UC San Diego rowing team was established in 1966 and practices on Mission Bay, roughly 10 miles from the main university campus. The rowing team is centered out of the Coggeshall Rowing Center on El Carmel Point in Mission Bay which houses the San Diego Rowing Club, the University of San Diego collegiate rowing program, and the UC San Diego collegiate rowing program. Men's rowing The Tritons are members of the Western Sprints Conference within the Intercollegiate Rowing Association. The Western Sprints conference has two automatic qualification positions for the IRA National Championship Regatta. The Tritons also have historic association with the Western Intercollegiate Rowing Association (WIRA) conference prior to the establishment of the Western Sprints Regatta. The Tritons have made six appearances at the National Championship, having first qualified in 2009. The next appearances were in 2011, 2013, 2017, 2018, and 2019 with the 2017–2019 seasons having been the only consecutive appearances in program history. Having never been nationally ranked prior to the 2007 season, UC San Diego has now spent time ranked in the top 25 of the U.S. Rowing Collegiate Poll in six of the last 11 seasons going into the 2020 season.The Western Sprints conference includes UC San Diego, University of San Diego, Santa Clara University, and Gonzaga University. The Tritons secured a conference championship with a sweep of the event in both 2018 and 2019 with the Varsity 8, Junior Varsity 8, and Third Varsity 8 enjoying a first place finish. UC San Diego has also enjoyed success at the WIRA Championship: a regional championship that takes places on Lake Natoma in Folsom, California. At WIRA's, the Triton's have always secured a position on the podium. The Tritons won the overall team championship in 2006, 2011, and 2019, including a monumental sweep of the Varsity 8, Second Varsity 8, and Third Varsity 8 races in 2019. Following the sweep, Zach Johnson, the head coach at the time, was named WIRA Coach of the Year. Women's rowing The Triton Women's team is a part of the NCAA Division I. On March 26, 2021, UC San Diego and the Colonial Athletic Association jointly announced that the Triton's women's rowing team had joined the conference effective immediately. Soccer Men's soccer The UC San Diego men's soccer team hosts its opponents at the Triton Soccer Stadium at RIMAC Field. In 2003, 2013, and 2014, it advanced to the first round of the NCAA West Regional. In 2013, they were the CCAA tournament runners-up. The best season in team history occurred in 2016, when the team advanced to the NCAA Division II Semifinals after claiming the CCAA league championship, CCAA tournament championship, and the NCAA West Region title. Women's soccer The UC San Diego women's soccer team plays its home matches at the Triton Soccer Stadium at RIMAC Field. In its first two seasons of Division II play, 2000 and 2001, the team was crowned CCAA Champions and NCAA National Champions. The Tritons again won the CCAA in 2002, 2003, 2005, 2006, 2008, 2011, 2012, 2015, 2016, and 2017, reaching the NCAA Final Four in 2003 and 2017 and being named NCAA Runners-Up in 2010 and 2012. They reached the NCAA West Regional 2nd Round in 2005, 2008, and 2009 and were named the regional runners-up in 2016, but were eliminated in the first round in 2002, 2007, 2011, and 2015. Since its promotion to Division II in 2000, the team has failed to reach the NCAA playoffs only three times, in 2004, 2013, and 2014, and has posted an undefeated CCAA record once, going 12–0 in league play and winning the tournament and division in 2016. Softball The UC San Diego softball team plays its home games at Triton Softball Stadium, adjacent to RIMAC Arena. The Tritons advanced to the NCAA West Regionals in 2001, 2002, 2007, 2008, 2009. 2011, 2012, 2013, and 2014. In 2011, they were the NCAA National Champions, having won the NCAA West Region and the CCAA. In 2012, they won the CCAA tournament and repeated as NCAA West Region Champions, and were eventually crowned the NCAA National Runners-Up. They won their second CCAA tournament in 2016. Swimming Men's Swimming The UC San Diego men's swim team competes in the Mountain Pacific Sports Federation, practicing and competing at the Canyonview Aquatic Center. Since joining Division I prior to the 2021-22 season, the Tritons have finished 4th and 5th in the 2022 and 2023 MPSF Championships, respectively. In 2022, Senior Ivan Kurakin won the 200 yard freestyle, while Freshman Aidan Simpson won the 200 yard breaststroke. Women's Swimming The UC San Diego women's swim team competes in the Mountain Pacific Sports Federation, practicing and competing at the Canyonview Aquatic Center. In 2022, their first year as a Division I program, the Triton women upset the then 5-time defending champions Hawaii to win the MPSF Championships, their first Conference Championship in any program since joining Division I. Fueled by 2 wins from Junior Katja Pavicevic (200 IM, 200 Breaststroke), as well as individual wins from Julissa Arzave (1650 Freestyle), Ciara Franke (200 Freestyle), and Tina Reuter (400 IM), and multiple relay victories, the Tritons edged out Hawaii by a meager 12.5 points.In 2023, the Tritons were unable to repeat as champions, finishing second behind Hawaii. Tennis Men's tennis The UC San Diego men's tennis team competes in the Intercollegiate Tennis Association and plays its home games at the Northview Tennis Courts. The team advanced to the NCAA Division II National Championships each year between 2001 and 2007, and returned there in 2010, 2011, 2013, and 2014. The team's best finish at the NCAA tournament came in 2007, when it was eliminated in the Final Four. Women's tennis The UC San Diego women's tennis team competes in the Intercollegiate Tennis Association and plays its home matches at the Northview Tennis Courts. They were undefeated CCAA champions every season between 2004 and 2009, advancing to the NCAA West Regional each year. They again won the CCAA in 2010, advancing to the regional championship with a 9–1 conference record. Volleyball Men's volleyball (Division I) The UC San Diego men's volleyball team competes in the Big West Conference, having joined from the Mountain Pacific Sports Federation for the 2018 season (2017–18 school year). The team's home matches against its Division I opponents are played at RIMAC Arena. The program's best finish in the new millennium came in 2009, when the team ended the season ranked ninth in the MPSF. Women's volleyball The UC San Diego women's volleyball team plays its home matches at RIMAC Arena. The program has made the postseason every year except 2005 and 2014 as well as the NCAA West Regional every year except 2005, 2014, 2015, and 2017. In 2001, the Tritons reached the NCAA Division II Final Four. The team won the CCAA regular season in 2004 with an undefeated league record. Water Polo Men's water polo The UC San Diego men's water polo team competes in the Western Water Polo Association against Division I opponents. They host their opponents at Canyonview Aquatic Center in Warren College. The Tritons have reached the NCAA Final Four in 1995, 1998, 1999, 2000, 2006, 2011, 2014, and 2015. They were the NCAA National Runners-Up in 2000. Women's water polo The UC San Diego women's water polo team competes in the Big West Conference against Division I opponents. They host their opponents at Canyonview Aquatic Center in Warren College. Esports UC San Diego has fielded multiple esports teams in a variety of games, both for team play and individual competition. Most notably the Splatoon team, Triton Splatoon, competed in the playoffs of two of the Twitch streamed Proton Splat Leagues for Splatoon 2, taking 4th place in season 4 after being defeated in the first round and going on an impressive run through the losers bracket, and 1st in season 6 after a close 11 game match across two best of 7 sets against team New Horizon in a rematch from their semifinals match. Former varsity sports Football UC San Diego has not fielded a football team except in Fall 1968 when a newly formed pigskin organization turned in a winless season and then folded for lack of interest. Since then, the subject of bringing NCAA football back to UC San Diego has been a recurring topic. Tom Ham, a local restaurateur and a supporter of UC San Diego football since the 1960s, has said that UC San Diego would have no future in San Diego without "big-time" football. Proponents of a major football team have projected benefits that include greater school spirit and a more well-rounded school experience for students as well as enhancing the school's national profile. Opposition to "big-time" football comes from a wide range of school faculty and administrators such Daniel Wulbert, Revelle College provost, who says that any boost to school spirit wouldn't be worth the sacrifice, and that he wants UC San Diego to "have a life for reasons other than watching hired athletes come and play." Both sides acknowledge that adding an 80- to 100-man football team would not only cost some US$1–1.5M annually, but that the initial outlay in equipment and facilities would be in the tens of millions. Furthermore, in order to comply with Title IX's requirement for equal sports opportunities for both sexes, some three women's teams (80–100 athletes) would have to be added, or three existing men's teams disbanded. Without the expense of football, UC San Diego has been characterized as having "the best all-around program, with the most success by the most student-athletes" in San Diego. Championships Appearances The UC San Diego Tritons competed in the NCAA Tournament across 20 active sports (1 co-ed, 9 men's, and 10 women's) 222 times at the Division II level. Baseball (11): 2007, 2008, 2009, 2010, 2011, 2012, 2014, 2015, 2017, 2018, 2019 Men's basketball (5): 2008, 2016, 2017, 2018, 2019 Women's basketball (12): 2004, 2006, 2007, 2008, 2009, 2010, 2012, 2013, 2016, 2017, 2018, 2019 Men's cross country (4): 2001, 2003, 2007, 2019 Women's cross country (7): 2002, 2003, 2004, 2005, 2006, 2007, 2014 Fencing (24): 1994, 1995, 1997, 1998, 1999, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019 Men's golf (2): 2004, 2019 Men's soccer (5): 2003, 2013, 2014, 2016, 2019 Women's Rowing (5): 2006, 2007, 2008, 2017, 2019 Women's soccer (17): 2000, 2001, 2002, 2003, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2015, 2016, 2017, 2018, 2019 Softball (11): 2002, 2007, 2008, 2009, 2011, 2012, 2013, 2014, 2016, 2018, 2019 Men's swimming and diving (19): 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019 Women's swimming and diving (19): 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019 Men's tennis (16): 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2013, 2014, 2016, 2017, 2018 Women's tennis (12): 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2016, 2018 Men's outdoor track and field (13): 2001, 2002, 2005, 2006, 2008, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2018 Women's outdoor track and field (14): 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2014, 2017 Women's volleyball (15): 2000, 2001, 2002, 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2015, 2019 Men's water polo (16): 1989, 1991, 1992, 1993, 1995, 1998, 1999, 2000, 2002, 2006, 2011, 2013, 2014, 2015, 2018, 2019 Women's water polo (8): 2011, 2013, 2014, 2015, 2016, 2017, 2018, 2019Men's Rowing is not governed by the NCAA but instead by the Intercollegiate Rowing Association (IRA). The Tritons have represented the University at the IRA National Championships six times. Men's Rowing (6): 2009, 2011, 2013, 2017, 2018, 2019 Team The Tritons of UC San Diego earned 3 NCAA championships at the Division II level. Women's (3) Soccer (2): 2000, 2001 Softball (1): 2011Results UC San Diego won 20 national championships at the NCAA Division III level. Men's golf: 1993 Men's soccer: 1988, 1991, 1993 Women's soccer: 1989, 1995, 1996, 1997, 1999 Women's tennis: 1985, 1987, 1989 Women's volleyball: 1981, 1984, 1986, 1987, 1988, 1990, 1997Below are twenty-four national club team championships: Co-ed badminton (4): 2001, 2003, 2005, 2006 (ABA) Men's badminton (3): 2003, 2005, 2006 (ABA) Women's badminton (4): 2001, 2003, 2005, 2006 (ABA) Men's rugby – Division II (2): 1998, 1999 (USA Rugby) Co-ed surfing (7): 1970, 1983, 1990, 1993, 1995, 1997, 2003 (NCSA) Women's triathlon (2): 2008, 2009 (USA Triathlon) Women's ultimate (2): 2002, 2019 (USA Ultimate) Co-ed water skiing – Division II (1): 2004 (NCWSA)Note: Those with no denoted division is assumed that the institution earned a national championship at the highest level. Individual UC San Diego had 47 Tritons win NCAA individual championships at the Division II level. At the NCAA Division III level, UC San Diego won 84 individual championships. Traditions Boosters UC San Diego recognizes two external organizations of athletic boosters: the Triton Athletic Associates is a booster group of parents, alumni, and friends who have each donated between US$50 and $2,500; and the UC San Diego Athletic Board is made up of donors who have given US$10,000 or more to athletic programs. On campus, spirit and support groups consist of the UC San Diego Pep Band, Triton Tide (a student engagement group), the UC San Diego Cheerleaders, and the UC San Diego Dance Team. Further opportunities for athletic involvement are available to students interested in team staffing and management. Mascot King Triton appears as a costumed character mascot. References External links Official website	has part(s)	{ "answer_start": [ 5162 ], "text": [ "UC San Diego Tritons baseball" ] }
The UC San Diego Tritons are the athletic teams that represent the University of California, San Diego. UC San Diego has 23 varsity sports teams, as well as esports teams, and offers student participation in a wide range of sports. As of July 1, 2020, all UC San Diego teams participate at the NCAA Division I (DI) level in the Big West Conference. During their time in NCAA Division II and the California Collegiate Athletic Association starting in the 2000–01 season, UC San Diego placed in the top 5 in the Division II NACDA Directors' Cup standings nine times, including three 2nd-place finishes. NCSA Athletic Recruiting ranked the Tritons as the nation's top Division II program for eight consecutive years.In May 2016, UC San Diego students voted to transition all sports teams to the NCAA Division I level. On November 27, 2017, it was announced that UC San Diego would begin the transition to NCAA Division I and join the Big West Conference on July 1, 2020. History Move to Division I In 2010, UC San Diego considered elevating its athletics to NCAA Division I for all sports. They were looking to join the Big West Conference. However, there were several problems. After the Big West added the University of Hawaii in 2010, they would have 10 teams, meaning any extra member would require more conference games in basketball, upsetting the current schedule balance. In addition, in order to meet the minimum Division I scholarship requirements, the student body would need to vote for a fee increase sometime during the 2011–2012 academic year. After the Big West elected not to invite UC San Diego in May 2011, plans were put on hold and UC San Diego remained a Division II team. However, a student-led movement resulted in a vote on a fee increase for UC San Diego students in the hopes to enhance the school's chances of becoming a Division I school. In March 2012, the UC San Diego student body rejected an increase in activity fees to support the move to Division I. The vote fell 11,407 to 6,470 (51% of the student body voted). In January 2016, Associated Students UC San Diego unanimously approved the wording of a new Division I referendum. In May, UC San Diego undergraduates voted to increase athletic fees by $480 per year and transition UC San Diego athletics to Division I. The fee increase will fund the athletic scholarships required for NCAA Division I schools. The move was approved by the UC San Diego Academic Senate in December 2016. UC San Diego's move remains contingent upon an invitation to join the Big West Conference.In a separate move by the Big West Conference to sponsor men's volleyball, Big West teams from the MPSF split to join their own conference that includes UC San Diego as an affiliate member starting in the 2017–18 school year (2018 season). The Tritons' joining the Big West as an affiliate for men's volleyball was not an indicator that the Tritons would be accepted as a full member yet since UC San Diego had long played the sport in the MPSF at a Division I level and was part of the original coalition talks with the Big West to split from MPSF men's volleyball. Early in April 2017, the San Diego Tribune reported that the Big West had rejected UC San Diego's application to join the conference. The Big West commission overseeing new members into the conference consists of the Presidents and Chancellors of every member school. There has not been a formal public confirmation of the rejection, but UC San Diego may still attempt to make moves to join the Big West or another conference (such as the Western Athletic Conference) until its 2018 deadline set by the referendum. However, on November 27, 2017, UC San Diego was accepted and officially started the journey towards the Big West conference along with Cal State Bakersfield. UC San Diego's women's water polo team joined the Big West in 2019, and UC San Diego began the required four year transition period on July 1, 2020 to be a full member on July 1, 2024. Sports sponsored A member of the Big West Conference, UC San Diego sponsors teams in ten men's, eleven women's, and one coed NCAA sanctioned sports. The school also sponsors a varsity men's rowing team, but men's rowing is not sanctioned by the NCAA. The rowing teams are members of the Western Intercollegiate Rowing Association. The men's water polo team is a member of the Western Water Polo Association. The fencing team is a member of the Intercollegiate Fencing Conference of Southern California. Men's volleyball and women's water polo both compete in the Big West Conference, with the former joining that league in 2017 and the latter in 2019, ahead of the school becoming a full member of the Big West on July 1, 2020 and beginning the transition to Division I. From Fall 2000 to Spring 2017, UC San Diego teams competed primarily in the California Collegiate Athletic Association. The school was awarded the Hiegert Commissioner's Trophy (awarded to the CCAA school with the highest aggregate ranking in eight sports) seven times—five consecutive years from 2006–2010 and again in 2016 and 2017. National champions are highlighted in bold and italicized. Baseball The UC San Diego Tritons baseball team is the varsity intercollegiate baseball team of the University of California, San Diego. The team plays its home games at Triton Ballpark. Basketball Men's basketball The UC San Diego Tritons men's basketball team represents the University of California, San Diego. The team plays its home games at RIMAC Arena. Women's basketball The UC San Diego women's basketball team plays its home games at RIMAC Arena. It has won the CCAA five times, during the 2006–07, 2008–09, 2009–10, 2012–13, and 2016–17 seasons. The Tritons advanced to the NCAA West Regional 1st Round in 2003–04, 2005–06, and 2009–10, and reached the 2nd Round in 2007–08 and 2008–09. They were the NCAA West Region runners-up in 2011–12 and 2015–16. In 2006–07, they reached the NCAA Final Four. Fencing The UC San Diego men's and women's fencing squads compete at Main Gym and RIMAC Arena. They competed in the Intercollegiate Fencing Conference of Southern California at the NCAA Division I level. The Tritons won this league's championship every year between 2005 and 2016. Under former Head Coach, Heidi Runyan, at least one Triton has qualified for the NCAA Division I Championships annually since 2005. The highest NCAA finish the Tritons have garnered was 13th in 2008 when six qualified to compete. In 2018, the men's and women's squads finished 14th in the NCAA circuit after sending five fencers to Penn State in State College, Pennsylvania where the competition was held. The team hosts the Annual BladeRunner Regional Open Circuit tournament as part of the United States Fencing Association. Rowing The UC San Diego rowing team was established in 1966 and practices on Mission Bay, roughly 10 miles from the main university campus. The rowing team is centered out of the Coggeshall Rowing Center on El Carmel Point in Mission Bay which houses the San Diego Rowing Club, the University of San Diego collegiate rowing program, and the UC San Diego collegiate rowing program. Men's rowing The Tritons are members of the Western Sprints Conference within the Intercollegiate Rowing Association. The Western Sprints conference has two automatic qualification positions for the IRA National Championship Regatta. The Tritons also have historic association with the Western Intercollegiate Rowing Association (WIRA) conference prior to the establishment of the Western Sprints Regatta. The Tritons have made six appearances at the National Championship, having first qualified in 2009. The next appearances were in 2011, 2013, 2017, 2018, and 2019 with the 2017–2019 seasons having been the only consecutive appearances in program history. Having never been nationally ranked prior to the 2007 season, UC San Diego has now spent time ranked in the top 25 of the U.S. Rowing Collegiate Poll in six of the last 11 seasons going into the 2020 season.The Western Sprints conference includes UC San Diego, University of San Diego, Santa Clara University, and Gonzaga University. The Tritons secured a conference championship with a sweep of the event in both 2018 and 2019 with the Varsity 8, Junior Varsity 8, and Third Varsity 8 enjoying a first place finish. UC San Diego has also enjoyed success at the WIRA Championship: a regional championship that takes places on Lake Natoma in Folsom, California. At WIRA's, the Triton's have always secured a position on the podium. The Tritons won the overall team championship in 2006, 2011, and 2019, including a monumental sweep of the Varsity 8, Second Varsity 8, and Third Varsity 8 races in 2019. Following the sweep, Zach Johnson, the head coach at the time, was named WIRA Coach of the Year. Women's rowing The Triton Women's team is a part of the NCAA Division I. On March 26, 2021, UC San Diego and the Colonial Athletic Association jointly announced that the Triton's women's rowing team had joined the conference effective immediately. Soccer Men's soccer The UC San Diego men's soccer team hosts its opponents at the Triton Soccer Stadium at RIMAC Field. In 2003, 2013, and 2014, it advanced to the first round of the NCAA West Regional. In 2013, they were the CCAA tournament runners-up. The best season in team history occurred in 2016, when the team advanced to the NCAA Division II Semifinals after claiming the CCAA league championship, CCAA tournament championship, and the NCAA West Region title. Women's soccer The UC San Diego women's soccer team plays its home matches at the Triton Soccer Stadium at RIMAC Field. In its first two seasons of Division II play, 2000 and 2001, the team was crowned CCAA Champions and NCAA National Champions. The Tritons again won the CCAA in 2002, 2003, 2005, 2006, 2008, 2011, 2012, 2015, 2016, and 2017, reaching the NCAA Final Four in 2003 and 2017 and being named NCAA Runners-Up in 2010 and 2012. They reached the NCAA West Regional 2nd Round in 2005, 2008, and 2009 and were named the regional runners-up in 2016, but were eliminated in the first round in 2002, 2007, 2011, and 2015. Since its promotion to Division II in 2000, the team has failed to reach the NCAA playoffs only three times, in 2004, 2013, and 2014, and has posted an undefeated CCAA record once, going 12–0 in league play and winning the tournament and division in 2016. Softball The UC San Diego softball team plays its home games at Triton Softball Stadium, adjacent to RIMAC Arena. The Tritons advanced to the NCAA West Regionals in 2001, 2002, 2007, 2008, 2009. 2011, 2012, 2013, and 2014. In 2011, they were the NCAA National Champions, having won the NCAA West Region and the CCAA. In 2012, they won the CCAA tournament and repeated as NCAA West Region Champions, and were eventually crowned the NCAA National Runners-Up. They won their second CCAA tournament in 2016. Swimming Men's Swimming The UC San Diego men's swim team competes in the Mountain Pacific Sports Federation, practicing and competing at the Canyonview Aquatic Center. Since joining Division I prior to the 2021-22 season, the Tritons have finished 4th and 5th in the 2022 and 2023 MPSF Championships, respectively. In 2022, Senior Ivan Kurakin won the 200 yard freestyle, while Freshman Aidan Simpson won the 200 yard breaststroke. Women's Swimming The UC San Diego women's swim team competes in the Mountain Pacific Sports Federation, practicing and competing at the Canyonview Aquatic Center. In 2022, their first year as a Division I program, the Triton women upset the then 5-time defending champions Hawaii to win the MPSF Championships, their first Conference Championship in any program since joining Division I. Fueled by 2 wins from Junior Katja Pavicevic (200 IM, 200 Breaststroke), as well as individual wins from Julissa Arzave (1650 Freestyle), Ciara Franke (200 Freestyle), and Tina Reuter (400 IM), and multiple relay victories, the Tritons edged out Hawaii by a meager 12.5 points.In 2023, the Tritons were unable to repeat as champions, finishing second behind Hawaii. Tennis Men's tennis The UC San Diego men's tennis team competes in the Intercollegiate Tennis Association and plays its home games at the Northview Tennis Courts. The team advanced to the NCAA Division II National Championships each year between 2001 and 2007, and returned there in 2010, 2011, 2013, and 2014. The team's best finish at the NCAA tournament came in 2007, when it was eliminated in the Final Four. Women's tennis The UC San Diego women's tennis team competes in the Intercollegiate Tennis Association and plays its home matches at the Northview Tennis Courts. They were undefeated CCAA champions every season between 2004 and 2009, advancing to the NCAA West Regional each year. They again won the CCAA in 2010, advancing to the regional championship with a 9–1 conference record. Volleyball Men's volleyball (Division I) The UC San Diego men's volleyball team competes in the Big West Conference, having joined from the Mountain Pacific Sports Federation for the 2018 season (2017–18 school year). The team's home matches against its Division I opponents are played at RIMAC Arena. The program's best finish in the new millennium came in 2009, when the team ended the season ranked ninth in the MPSF. Women's volleyball The UC San Diego women's volleyball team plays its home matches at RIMAC Arena. The program has made the postseason every year except 2005 and 2014 as well as the NCAA West Regional every year except 2005, 2014, 2015, and 2017. In 2001, the Tritons reached the NCAA Division II Final Four. The team won the CCAA regular season in 2004 with an undefeated league record. Water Polo Men's water polo The UC San Diego men's water polo team competes in the Western Water Polo Association against Division I opponents. They host their opponents at Canyonview Aquatic Center in Warren College. The Tritons have reached the NCAA Final Four in 1995, 1998, 1999, 2000, 2006, 2011, 2014, and 2015. They were the NCAA National Runners-Up in 2000. Women's water polo The UC San Diego women's water polo team competes in the Big West Conference against Division I opponents. They host their opponents at Canyonview Aquatic Center in Warren College. Esports UC San Diego has fielded multiple esports teams in a variety of games, both for team play and individual competition. Most notably the Splatoon team, Triton Splatoon, competed in the playoffs of two of the Twitch streamed Proton Splat Leagues for Splatoon 2, taking 4th place in season 4 after being defeated in the first round and going on an impressive run through the losers bracket, and 1st in season 6 after a close 11 game match across two best of 7 sets against team New Horizon in a rematch from their semifinals match. Former varsity sports Football UC San Diego has not fielded a football team except in Fall 1968 when a newly formed pigskin organization turned in a winless season and then folded for lack of interest. Since then, the subject of bringing NCAA football back to UC San Diego has been a recurring topic. Tom Ham, a local restaurateur and a supporter of UC San Diego football since the 1960s, has said that UC San Diego would have no future in San Diego without "big-time" football. Proponents of a major football team have projected benefits that include greater school spirit and a more well-rounded school experience for students as well as enhancing the school's national profile. Opposition to "big-time" football comes from a wide range of school faculty and administrators such Daniel Wulbert, Revelle College provost, who says that any boost to school spirit wouldn't be worth the sacrifice, and that he wants UC San Diego to "have a life for reasons other than watching hired athletes come and play." Both sides acknowledge that adding an 80- to 100-man football team would not only cost some US$1–1.5M annually, but that the initial outlay in equipment and facilities would be in the tens of millions. Furthermore, in order to comply with Title IX's requirement for equal sports opportunities for both sexes, some three women's teams (80–100 athletes) would have to be added, or three existing men's teams disbanded. Without the expense of football, UC San Diego has been characterized as having "the best all-around program, with the most success by the most student-athletes" in San Diego. Championships Appearances The UC San Diego Tritons competed in the NCAA Tournament across 20 active sports (1 co-ed, 9 men's, and 10 women's) 222 times at the Division II level. Baseball (11): 2007, 2008, 2009, 2010, 2011, 2012, 2014, 2015, 2017, 2018, 2019 Men's basketball (5): 2008, 2016, 2017, 2018, 2019 Women's basketball (12): 2004, 2006, 2007, 2008, 2009, 2010, 2012, 2013, 2016, 2017, 2018, 2019 Men's cross country (4): 2001, 2003, 2007, 2019 Women's cross country (7): 2002, 2003, 2004, 2005, 2006, 2007, 2014 Fencing (24): 1994, 1995, 1997, 1998, 1999, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019 Men's golf (2): 2004, 2019 Men's soccer (5): 2003, 2013, 2014, 2016, 2019 Women's Rowing (5): 2006, 2007, 2008, 2017, 2019 Women's soccer (17): 2000, 2001, 2002, 2003, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2015, 2016, 2017, 2018, 2019 Softball (11): 2002, 2007, 2008, 2009, 2011, 2012, 2013, 2014, 2016, 2018, 2019 Men's swimming and diving (19): 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019 Women's swimming and diving (19): 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019 Men's tennis (16): 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2013, 2014, 2016, 2017, 2018 Women's tennis (12): 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2016, 2018 Men's outdoor track and field (13): 2001, 2002, 2005, 2006, 2008, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2018 Women's outdoor track and field (14): 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2014, 2017 Women's volleyball (15): 2000, 2001, 2002, 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2015, 2019 Men's water polo (16): 1989, 1991, 1992, 1993, 1995, 1998, 1999, 2000, 2002, 2006, 2011, 2013, 2014, 2015, 2018, 2019 Women's water polo (8): 2011, 2013, 2014, 2015, 2016, 2017, 2018, 2019Men's Rowing is not governed by the NCAA but instead by the Intercollegiate Rowing Association (IRA). The Tritons have represented the University at the IRA National Championships six times. Men's Rowing (6): 2009, 2011, 2013, 2017, 2018, 2019 Team The Tritons of UC San Diego earned 3 NCAA championships at the Division II level. Women's (3) Soccer (2): 2000, 2001 Softball (1): 2011Results UC San Diego won 20 national championships at the NCAA Division III level. Men's golf: 1993 Men's soccer: 1988, 1991, 1993 Women's soccer: 1989, 1995, 1996, 1997, 1999 Women's tennis: 1985, 1987, 1989 Women's volleyball: 1981, 1984, 1986, 1987, 1988, 1990, 1997Below are twenty-four national club team championships: Co-ed badminton (4): 2001, 2003, 2005, 2006 (ABA) Men's badminton (3): 2003, 2005, 2006 (ABA) Women's badminton (4): 2001, 2003, 2005, 2006 (ABA) Men's rugby – Division II (2): 1998, 1999 (USA Rugby) Co-ed surfing (7): 1970, 1983, 1990, 1993, 1995, 1997, 2003 (NCSA) Women's triathlon (2): 2008, 2009 (USA Triathlon) Women's ultimate (2): 2002, 2019 (USA Ultimate) Co-ed water skiing – Division II (1): 2004 (NCWSA)Note: Those with no denoted division is assumed that the institution earned a national championship at the highest level. Individual UC San Diego had 47 Tritons win NCAA individual championships at the Division II level. At the NCAA Division III level, UC San Diego won 84 individual championships. Traditions Boosters UC San Diego recognizes two external organizations of athletic boosters: the Triton Athletic Associates is a booster group of parents, alumni, and friends who have each donated between US$50 and $2,500; and the UC San Diego Athletic Board is made up of donors who have given US$10,000 or more to athletic programs. On campus, spirit and support groups consist of the UC San Diego Pep Band, Triton Tide (a student engagement group), the UC San Diego Cheerleaders, and the UC San Diego Dance Team. Further opportunities for athletic involvement are available to students interested in team staffing and management. Mascot King Triton appears as a costumed character mascot. References External links Official website	represents	{ "answer_start": [ 67 ], "text": [ "University of California, San Diego" ] }
Hoda Muthana (born October 28, 1994) is a U.S.-born Yemeni woman who emigrated from the United States to Syria to join ISIS in November 2014. She surrendered in January 2019 to coalition forces fighting ISIS in Syria and has been denied access back to the United States after a U.S. court ruling annulled her American citizenship. When she was born, her father was a Yemeni diplomat, making her ineligible for American citizenship by birth. Early life Muthana was born in Hackensack, New Jersey on October 28, 1994. Her father was a Yemeni diplomat, although it is disputed whether he was a diplomat at the time of her birth or whether he resigned months before. Muthana was raised in Hoover, Alabama and attended Hoover High School before leaving the United States to join ISIS in November 2014 using funds that her parents had provided for her college tuition. Time in ISIS In December 2014, Muthana married Suhan Rahman, an Australian jihadist who went by the name Abu Jihad Al-Australi. On Twitter, she advocated for terror attacks against civilians in the United States and encouraged more residents to travel to ISIS-controlled territory and support the caliphate. The Guardian reported that Muthana claimed that her Twitter account was hacked by others. In an interview with ABC News on February 19, 2019, when she was asked about a tweet in which she called for the murder of Americans at Veterans and Memorial Day parades, Muthana replied "I can't even believe I thought of that."Muthana's husband, Rahman, was killed in Syria in March 2015. She then married a Tunisian fighter and gave birth to a son. Muthana stated that she began to question her allegiance to the caliphate around this time. Her second husband was killed fighting in Mosul in 2017, and she fled from Raqqa to Mayadin to Hajin and finally to Shafa in eastern Syria. She married and divorced a third man around this time. Muthana befriended Kimberly Gwen Polman, a dual Canadian-U.S. citizen, when the jihadi enclave had shrunk to just a few square miles. Food was so scarce that they were reduced to boiling grass for nourishment. They agreed to try to escape the enclave, although Polman said that her first attempt to defect had led to her being imprisoned, tortured and raped. Muthana escaped from Shafa and surrendered to American troops on January 10, 2019. Both Muthana and Polman were placed in the Al-Hawl refugee camp in Syria. Muthana expressed their desire to return to the United States.BuzzFeed conducted an interview with Muthana, her father, and a friend in 2015. They reported that after her father gave her a cell phone, she created a Twitter account her parents were not aware of, which eventually gained thousands of followers. The friend they interviewed said she may have been one of the only people who knew her in both real life and through Twitter. Buzzfeed respected her friend's desire to remain anonymous. She said that there was a gulf between Muthana's real world self and the more radical persona she adopted on Twitter, offering as an example that Muthana claimed she had worn modest jilbābs and abayas since eighth grade, when she had only adopted modest dress recently.In an interview with The New York Times, Muthana described how newly arrived female sympathizers like her were made to surrender their cell phones, and confined to a locked barracks, where they were held available as potential brides for jihadi fighters. Citizenship In January 2016, the Obama Administration revoked Muthana's passport, and stated in a letter that she was not a birthright citizen because her father's termination of diplomatic status had not been officially documented until February 1995.President Trump instructed Secretary of State Mike Pompeo to not allow her back into the country. Pompeo released a press statement that read: "Ms. Hoda Muthana is not a U.S. citizen and will not be admitted into the United States. She does not have any legal basis, no valid U.S. passport, no right to a passport, nor any visa to travel to the United States. We continue to strongly advise all U.S. citizens not to travel to Syria." Her lawyer, Charles Swift disputes the government's argument regarding birthright citizenship, asserting her father was discharged from his diplomatic position a month before she was born. On February 21, 2019, Muthana's father, Ahmed Ali Muthana, filed an emergency lawsuit, asking the federal government to affirm Muthana's citizenship and allow her to return to the United States.In November 2019, a federal judge ruled that she did not have American citizenship.In 2021, the DC Circuit Court of Appeals upheld the decision of the District Court, ruling that Muthana is not a US citizen. In 2022, the United States Supreme Court declined to hear her appeal. Later developments In April 2021, her sister was arrested while allegedly attempting to join ISIS. == References ==	place of birth	{ "answer_start": [ 473 ], "text": [ "Hackensack" ] }
Hoda Muthana (born October 28, 1994) is a U.S.-born Yemeni woman who emigrated from the United States to Syria to join ISIS in November 2014. She surrendered in January 2019 to coalition forces fighting ISIS in Syria and has been denied access back to the United States after a U.S. court ruling annulled her American citizenship. When she was born, her father was a Yemeni diplomat, making her ineligible for American citizenship by birth. Early life Muthana was born in Hackensack, New Jersey on October 28, 1994. Her father was a Yemeni diplomat, although it is disputed whether he was a diplomat at the time of her birth or whether he resigned months before. Muthana was raised in Hoover, Alabama and attended Hoover High School before leaving the United States to join ISIS in November 2014 using funds that her parents had provided for her college tuition. Time in ISIS In December 2014, Muthana married Suhan Rahman, an Australian jihadist who went by the name Abu Jihad Al-Australi. On Twitter, she advocated for terror attacks against civilians in the United States and encouraged more residents to travel to ISIS-controlled territory and support the caliphate. The Guardian reported that Muthana claimed that her Twitter account was hacked by others. In an interview with ABC News on February 19, 2019, when she was asked about a tweet in which she called for the murder of Americans at Veterans and Memorial Day parades, Muthana replied "I can't even believe I thought of that."Muthana's husband, Rahman, was killed in Syria in March 2015. She then married a Tunisian fighter and gave birth to a son. Muthana stated that she began to question her allegiance to the caliphate around this time. Her second husband was killed fighting in Mosul in 2017, and she fled from Raqqa to Mayadin to Hajin and finally to Shafa in eastern Syria. She married and divorced a third man around this time. Muthana befriended Kimberly Gwen Polman, a dual Canadian-U.S. citizen, when the jihadi enclave had shrunk to just a few square miles. Food was so scarce that they were reduced to boiling grass for nourishment. They agreed to try to escape the enclave, although Polman said that her first attempt to defect had led to her being imprisoned, tortured and raped. Muthana escaped from Shafa and surrendered to American troops on January 10, 2019. Both Muthana and Polman were placed in the Al-Hawl refugee camp in Syria. Muthana expressed their desire to return to the United States.BuzzFeed conducted an interview with Muthana, her father, and a friend in 2015. They reported that after her father gave her a cell phone, she created a Twitter account her parents were not aware of, which eventually gained thousands of followers. The friend they interviewed said she may have been one of the only people who knew her in both real life and through Twitter. Buzzfeed respected her friend's desire to remain anonymous. She said that there was a gulf between Muthana's real world self and the more radical persona she adopted on Twitter, offering as an example that Muthana claimed she had worn modest jilbābs and abayas since eighth grade, when she had only adopted modest dress recently.In an interview with The New York Times, Muthana described how newly arrived female sympathizers like her were made to surrender their cell phones, and confined to a locked barracks, where they were held available as potential brides for jihadi fighters. Citizenship In January 2016, the Obama Administration revoked Muthana's passport, and stated in a letter that she was not a birthright citizen because her father's termination of diplomatic status had not been officially documented until February 1995.President Trump instructed Secretary of State Mike Pompeo to not allow her back into the country. Pompeo released a press statement that read: "Ms. Hoda Muthana is not a U.S. citizen and will not be admitted into the United States. She does not have any legal basis, no valid U.S. passport, no right to a passport, nor any visa to travel to the United States. We continue to strongly advise all U.S. citizens not to travel to Syria." Her lawyer, Charles Swift disputes the government's argument regarding birthright citizenship, asserting her father was discharged from his diplomatic position a month before she was born. On February 21, 2019, Muthana's father, Ahmed Ali Muthana, filed an emergency lawsuit, asking the federal government to affirm Muthana's citizenship and allow her to return to the United States.In November 2019, a federal judge ruled that she did not have American citizenship.In 2021, the DC Circuit Court of Appeals upheld the decision of the District Court, ruling that Muthana is not a US citizen. In 2022, the United States Supreme Court declined to hear her appeal. Later developments In April 2021, her sister was arrested while allegedly attempting to join ISIS. == References ==	sex or gender	{ "answer_start": [ 3259 ], "text": [ "female" ] }
Hoda Muthana (born October 28, 1994) is a U.S.-born Yemeni woman who emigrated from the United States to Syria to join ISIS in November 2014. She surrendered in January 2019 to coalition forces fighting ISIS in Syria and has been denied access back to the United States after a U.S. court ruling annulled her American citizenship. When she was born, her father was a Yemeni diplomat, making her ineligible for American citizenship by birth. Early life Muthana was born in Hackensack, New Jersey on October 28, 1994. Her father was a Yemeni diplomat, although it is disputed whether he was a diplomat at the time of her birth or whether he resigned months before. Muthana was raised in Hoover, Alabama and attended Hoover High School before leaving the United States to join ISIS in November 2014 using funds that her parents had provided for her college tuition. Time in ISIS In December 2014, Muthana married Suhan Rahman, an Australian jihadist who went by the name Abu Jihad Al-Australi. On Twitter, she advocated for terror attacks against civilians in the United States and encouraged more residents to travel to ISIS-controlled territory and support the caliphate. The Guardian reported that Muthana claimed that her Twitter account was hacked by others. In an interview with ABC News on February 19, 2019, when she was asked about a tweet in which she called for the murder of Americans at Veterans and Memorial Day parades, Muthana replied "I can't even believe I thought of that."Muthana's husband, Rahman, was killed in Syria in March 2015. She then married a Tunisian fighter and gave birth to a son. Muthana stated that she began to question her allegiance to the caliphate around this time. Her second husband was killed fighting in Mosul in 2017, and she fled from Raqqa to Mayadin to Hajin and finally to Shafa in eastern Syria. She married and divorced a third man around this time. Muthana befriended Kimberly Gwen Polman, a dual Canadian-U.S. citizen, when the jihadi enclave had shrunk to just a few square miles. Food was so scarce that they were reduced to boiling grass for nourishment. They agreed to try to escape the enclave, although Polman said that her first attempt to defect had led to her being imprisoned, tortured and raped. Muthana escaped from Shafa and surrendered to American troops on January 10, 2019. Both Muthana and Polman were placed in the Al-Hawl refugee camp in Syria. Muthana expressed their desire to return to the United States.BuzzFeed conducted an interview with Muthana, her father, and a friend in 2015. They reported that after her father gave her a cell phone, she created a Twitter account her parents were not aware of, which eventually gained thousands of followers. The friend they interviewed said she may have been one of the only people who knew her in both real life and through Twitter. Buzzfeed respected her friend's desire to remain anonymous. She said that there was a gulf between Muthana's real world self and the more radical persona she adopted on Twitter, offering as an example that Muthana claimed she had worn modest jilbābs and abayas since eighth grade, when she had only adopted modest dress recently.In an interview with The New York Times, Muthana described how newly arrived female sympathizers like her were made to surrender their cell phones, and confined to a locked barracks, where they were held available as potential brides for jihadi fighters. Citizenship In January 2016, the Obama Administration revoked Muthana's passport, and stated in a letter that she was not a birthright citizen because her father's termination of diplomatic status had not been officially documented until February 1995.President Trump instructed Secretary of State Mike Pompeo to not allow her back into the country. Pompeo released a press statement that read: "Ms. Hoda Muthana is not a U.S. citizen and will not be admitted into the United States. She does not have any legal basis, no valid U.S. passport, no right to a passport, nor any visa to travel to the United States. We continue to strongly advise all U.S. citizens not to travel to Syria." Her lawyer, Charles Swift disputes the government's argument regarding birthright citizenship, asserting her father was discharged from his diplomatic position a month before she was born. On February 21, 2019, Muthana's father, Ahmed Ali Muthana, filed an emergency lawsuit, asking the federal government to affirm Muthana's citizenship and allow her to return to the United States.In November 2019, a federal judge ruled that she did not have American citizenship.In 2021, the DC Circuit Court of Appeals upheld the decision of the District Court, ruling that Muthana is not a US citizen. In 2022, the United States Supreme Court declined to hear her appeal. Later developments In April 2021, her sister was arrested while allegedly attempting to join ISIS. == References ==	educated at	{ "answer_start": [ 715 ], "text": [ "Hoover High School" ] }
Hoda Muthana (born October 28, 1994) is a U.S.-born Yemeni woman who emigrated from the United States to Syria to join ISIS in November 2014. She surrendered in January 2019 to coalition forces fighting ISIS in Syria and has been denied access back to the United States after a U.S. court ruling annulled her American citizenship. When she was born, her father was a Yemeni diplomat, making her ineligible for American citizenship by birth. Early life Muthana was born in Hackensack, New Jersey on October 28, 1994. Her father was a Yemeni diplomat, although it is disputed whether he was a diplomat at the time of her birth or whether he resigned months before. Muthana was raised in Hoover, Alabama and attended Hoover High School before leaving the United States to join ISIS in November 2014 using funds that her parents had provided for her college tuition. Time in ISIS In December 2014, Muthana married Suhan Rahman, an Australian jihadist who went by the name Abu Jihad Al-Australi. On Twitter, she advocated for terror attacks against civilians in the United States and encouraged more residents to travel to ISIS-controlled territory and support the caliphate. The Guardian reported that Muthana claimed that her Twitter account was hacked by others. In an interview with ABC News on February 19, 2019, when she was asked about a tweet in which she called for the murder of Americans at Veterans and Memorial Day parades, Muthana replied "I can't even believe I thought of that."Muthana's husband, Rahman, was killed in Syria in March 2015. She then married a Tunisian fighter and gave birth to a son. Muthana stated that she began to question her allegiance to the caliphate around this time. Her second husband was killed fighting in Mosul in 2017, and she fled from Raqqa to Mayadin to Hajin and finally to Shafa in eastern Syria. She married and divorced a third man around this time. Muthana befriended Kimberly Gwen Polman, a dual Canadian-U.S. citizen, when the jihadi enclave had shrunk to just a few square miles. Food was so scarce that they were reduced to boiling grass for nourishment. They agreed to try to escape the enclave, although Polman said that her first attempt to defect had led to her being imprisoned, tortured and raped. Muthana escaped from Shafa and surrendered to American troops on January 10, 2019. Both Muthana and Polman were placed in the Al-Hawl refugee camp in Syria. Muthana expressed their desire to return to the United States.BuzzFeed conducted an interview with Muthana, her father, and a friend in 2015. They reported that after her father gave her a cell phone, she created a Twitter account her parents were not aware of, which eventually gained thousands of followers. The friend they interviewed said she may have been one of the only people who knew her in both real life and through Twitter. Buzzfeed respected her friend's desire to remain anonymous. She said that there was a gulf between Muthana's real world self and the more radical persona she adopted on Twitter, offering as an example that Muthana claimed she had worn modest jilbābs and abayas since eighth grade, when she had only adopted modest dress recently.In an interview with The New York Times, Muthana described how newly arrived female sympathizers like her were made to surrender their cell phones, and confined to a locked barracks, where they were held available as potential brides for jihadi fighters. Citizenship In January 2016, the Obama Administration revoked Muthana's passport, and stated in a letter that she was not a birthright citizen because her father's termination of diplomatic status had not been officially documented until February 1995.President Trump instructed Secretary of State Mike Pompeo to not allow her back into the country. Pompeo released a press statement that read: "Ms. Hoda Muthana is not a U.S. citizen and will not be admitted into the United States. She does not have any legal basis, no valid U.S. passport, no right to a passport, nor any visa to travel to the United States. We continue to strongly advise all U.S. citizens not to travel to Syria." Her lawyer, Charles Swift disputes the government's argument regarding birthright citizenship, asserting her father was discharged from his diplomatic position a month before she was born. On February 21, 2019, Muthana's father, Ahmed Ali Muthana, filed an emergency lawsuit, asking the federal government to affirm Muthana's citizenship and allow her to return to the United States.In November 2019, a federal judge ruled that she did not have American citizenship.In 2021, the DC Circuit Court of Appeals upheld the decision of the District Court, ruling that Muthana is not a US citizen. In 2022, the United States Supreme Court declined to hear her appeal. Later developments In April 2021, her sister was arrested while allegedly attempting to join ISIS. == References ==	given name	{ "answer_start": [ 0 ], "text": [ "Hoda" ] }
Oroville may refer to: Oroville, California, United States Oroville, Washington, United StatesOther usesLake Oroville, in Butte County, California, USA Oroville Dam, in Butte County, California, USA Oroville Municipal Airport, in Butte County, California, USA See also Oraville (disambiguation) Orville (disambiguation) Auroville, experimental community in India	located in the administrative territorial entity	{ "answer_start": [ 123 ], "text": [ "Butte County" ] }
Oroville may refer to: Oroville, California, United States Oroville, Washington, United StatesOther usesLake Oroville, in Butte County, California, USA Oroville Dam, in Butte County, California, USA Oroville Municipal Airport, in Butte County, California, USA See also Oraville (disambiguation) Orville (disambiguation) Auroville, experimental community in India	Commons category	{ "answer_start": [ 24 ], "text": [ "Oroville, California" ] }
Oroville may refer to: Oroville, California, United States Oroville, Washington, United StatesOther usesLake Oroville, in Butte County, California, USA Oroville Dam, in Butte County, California, USA Oroville Municipal Airport, in Butte County, California, USA See also Oraville (disambiguation) Orville (disambiguation) Auroville, experimental community in India	capital of	{ "answer_start": [ 123 ], "text": [ "Butte County" ] }
Ruditapes largillierti is a saltwater clam, a marine bivalve mollusc in the family Veneridae, the Venus clams. They are moderately large for their genus (45–65 mm long), elongate and subrectangular, thick and solid, with smooth ventral margin.The species has limited use to people and the seafood industry because it resides in very deep ocean water and contains a very common pearl. References CSIRO GNS Science	taxon rank	{ "answer_start": [ 247 ], "text": [ "species" ] }
Ruditapes largillierti is a saltwater clam, a marine bivalve mollusc in the family Veneridae, the Venus clams. They are moderately large for their genus (45–65 mm long), elongate and subrectangular, thick and solid, with smooth ventral margin.The species has limited use to people and the seafood industry because it resides in very deep ocean water and contains a very common pearl. References CSIRO GNS Science	parent taxon	{ "answer_start": [ 0 ], "text": [ "Ruditapes" ] }
Ruditapes largillierti is a saltwater clam, a marine bivalve mollusc in the family Veneridae, the Venus clams. They are moderately large for their genus (45–65 mm long), elongate and subrectangular, thick and solid, with smooth ventral margin.The species has limited use to people and the seafood industry because it resides in very deep ocean water and contains a very common pearl. References CSIRO GNS Science	taxon name	{ "answer_start": [ 0 ], "text": [ "Ruditapes largillierti" ] }
European was a brand of Formula One engines. European sponsored Minardi in the 2001 season and acted as the engine supplier to the team. The engines were Ford-built engines, branded as European. History European Aviation was a regular sponsor across Formula One and Formula 3000 during the late 1990s and early 2000s, initially with the Tyrrell team, and later with Jordan Grand Prix and Arrows Grand Prix.In 2001, European Aviation owner Paul Stoddart acquired the Minardi team. It became known as European Minardi, and ran with European branding on the cars alongside the engines being branded as "European". Complete Formula One results (key) (results in bold indicate pole position) == References ==	sport	{ "answer_start": [ 24 ], "text": [ "Formula One" ] }
Pescadero Creek is a major stream in Santa Cruz and San Mateo counties in California, United States. At 26.6 miles (42.8 km), it is the longest stream in San Mateo County and flows all year from springs in the Santa Cruz Mountains. Its source is at 1,880 feet (570 m) above sea level on the western edge of Castle Rock State Park, with additional headwaters in Portola Redwoods State Park, and its course traverses Pescadero Creek County Park and San Mateo County Memorial Park before entering Pescadero Marsh Natural Preserve at Pescadero State Beach and thence to the Pacific Ocean 14.4 miles (23 km) south of Half Moon Bay. History Pescadero is Spanish for "fishing place". In early Mexican land grants or disueños, John Gilroy stated "The Castros, I and an Indian gave it that name in 1814, being a place where we used to catch salmon."Arroyo del Pescadero appears on the disueños of the 1830s. The 1860s' Coast Survey called it the Pescador River. Spanish-speaking people founded the town of Pescadero, California in 1856.The pre-European Pescadero watershed was occupied by the Ohlone. The Quirostes controlled the area from Bean Hollow Creek southward to Año Nuevo Creek and inland to Butano Ridge. The Oljon controlled from the lower San Gregorio Creek drainage southward to Bean Hollow Creek, including the lower Pescadero and Butano drainages. The Cotogen held the land in and around Purisima Creek. When the Portolà Expedition traveled on horseback along the immediate coast on October 24, 1769, Padre Juan Crespí wrote, "Only in the watercourses are any trees to be seen; elsewhere we saw nothing but grass, and that was burned." The Ohlone managed the land with the most effective tool they had, fire.The Santa Cruz Lumber Company built a sawmill at Saratoga Gap in 1923. The company formed a log pond by building a wooden dam in the creek, and the sawmill was built over the creek downstream of the log pond. The sawmill employed fifty to eighty men manufacturing sixty-thousand board foot of redwood and Douglas fir lumber daily. A forest railway was extended more than 7 miles (11 km) up Pescadero Creek to bring logs down to the sawmill after loggers had felled all trees close enough to be winched to the mill with cables. Railway operations began when the company purchased a 2-truck Shay locomotive (Lima Locomotive Works number 2461) from the San Joaquin and Eastern Railroad in 1930 and continued until the railroad grade was converted to a truck road in 1950. The sawmill ceased operations in 1972.Farmers began building levees and drained small areas of the marsh by the late 1920s. Substantial levee building and conversion of marshlands to agriculture occurred during the 1930s, and continued through the early 1960s. The State began acquiring land in the 1960s. In the early 1960s local farmers used a dragline to remove sediment from Butano Creek channel below Pescadero Bridge for several thousand feet down stream. The sediment removed was used to build a 6,000 foot levee on the west side of Butano Creek. Other levees were built to keep salt water out of agricultural fields. California Department of Fish and Game (DFG) required the dragline practice to stop following the introduction of new fish protection laws in 1963.The Highway One bridge was rebuilt (1989–90) with fewer supports and closer to the ocean to minimize effects on the stream and lagoon; the original bridge had been built in the early 1940s. Ecology Intensive logging and watershed development, also beginning in the late 1920s or early 1930s, has dramatically increased sedimentation in Butano and Pescadero creeks. Both streams are listed under the federal Clean Water Act as impaired water bodies for sediment. Concerns about agricultural pesticide runoff into the marsh prompted a report prepared by DFG. Jong confirmed eutrophic (high nutrient) conditions in the marsh and found that algae blooms raise dissolve oxygen (DO) levels to saturation during the day and deplete levels during night respiration. Jong speculated that the low night DO could result in fish kills. The DFG study found levels of pesticides potentially toxic to fish in the sediment. In the mid-1980s the west bank levee of Butano Creek was breached about 50 feet downstream of Pescadero Road Bridge in order to reduce flood flows down the Butano Creek channel in the marsh. Breaches in other levees of the North Butano Marsh were also made to improve circulation.Historically, both Pescadero Creek and Butano Creek, as well as several tributary streams, supported runs of steelhead trout (Oncorhynchus mykiss) and coho salmon (Oncorhynchus kisutch). Steelhead are still present, but there have been only sparse reports of coho in the watershed in recent years. Before logging removed much of the dense forest cover of this area in the middle of the 20th century, these streams were shaded, with frequent, stable pools created by fallen trees, bedrock outcrops, and boulders, and an abundant, if not steady, supply of gravel. With cool stream temperatures and reliable flows through the summer, they provided excellent habitat for salmon and trout, and both Pescadero Creek and Butano Creek were renowned sports fishing streams for vacationing San Franciscans in the late 19th century. According to a study by Professor Jerry Smith of San Jose State University, estimates in 1985 showed that 10,000 steelhead trout were rearing in the lagoon. As of 2008, 750 steelhead were counted in the same area. With the exception of a few juvenile coho observed in Peters Creek in 1999, salmon have been absent from the watershed until a 2003 release of 17,000 hatchery-raised coho smolts in Pescadero Creek. Very few of these coho have returned to the creek. In spring 2015, biologists discovered three coho salmon (with tags from the nearby Scott Creek hatchery) spawning in Pescadero Creek.California Golden Beaver (Castor canadensis subauratus) were re-introduced to Pescadero Creek around 1937-1938 by the DFG after near extinction in California in the early twentieth century. The beavers continue to thrive and although concerns about flooding related to beaver dams occurs, there is evidence that beaver in the lower channel in the 1950s reduced sediment movement through the system, especially since the late 1980s. Beaver improve salmonid abundance and size as their beaver ponds recharge the water table which, in turn, replenishes stream flows in the dry season and by providing ideal over-summering habitat. Contrary to popular myth, most beaver dams do not pose barriers to trout and salmon migration, although they may be restricted seasonally during periods of low stream flows. An extensive review recently proved that beaver were historically native to all of California except the most arid deserts, including coastal California. Beaver sign (Castor canadensis) was recently documented in the newly restored Butano Creek channel just above the Pescadero lagoon in September, 2022 (See photo). Pescadero Marsh Located at the confluence of Pescadero and Butano Creeks, the area known as Pescadero Marsh has for decades been a thriving habitat for both migratory and native wildlife. Besides being a refuge and nesting ground for wintering waterfowl, the marsh is a critical spawning area and nursery for coho salmon, steelhead trout, tidewater goby, and many other threatened or endangered fish, amphibian, and reptile species. Since 1995, annual fish "die-offs" of hundreds of juvenile fish, crabs, and other species occur in the late fall when the sandbar barrier between the lagoon and the ocean is breached. As water levels fluctuate, many species are cut off from supportive habitat, and the entire eco-system degrades. Since 1998 concerned citizens and other wildlife agencies have repeatedly asked California State Parks to take immediate corrective action. The Parks Department has failed to respond, and has instead moved to request further studies. Meanwhile, native species populations in the marsh have reached critically low levels. The Pescadero Lagoon Science Panel was established in 2013 to provide independent scientific expertise in support of management decisions and possible restoration actions for Pescadero marsh and lagoon. Steelhead restoration A federal project to revive the steelhead trout population showed success in 2012, and may be continued in 2013. Watershed The Pescadero-Butano watershed is the largest coastal watershed between the Golden Gate and the San Lorenzo River. The watershed's two principal streams, Pescadero Creek and Butano Creek, which have their confluence in Pescadero Marsh, drain 81 square miles (210 km2) of the Santa Cruz Mountains. Peters Creek in Portola Redwoods State Park, Oil Creek, Slate Creek and Butano Creek are the largest of many tributaries of Pescadero Creek. Tributaries Butano Creek Bradley Creek Chandler Gulch Honsinger Creek Windmill Gulch Big Chicken Hollow Little Chicken Hollow Newell Gulch Roy Gulch Blomquist Creek Peterson Creek Hoffman Creek McCormick Creek Harwood Creek Dark Gulch Keyston Creek Carriger Creek Rhododendron Creek Tarwater Creek Peters Creek Evans Creek Bear Creek Lambert Creek Fall Creek Iverson Creek Slate Creek Oil Creek Little Boulder Creek Waterman Creek References External links U.S. Geological Survey Geographic Names Information System: Pescadero Creek Pescadero-Butano Watershed Sediment and Habitat Management Plan Pescadero Marsh Annotated Bibliography at UC Berkeley San Mateo County Resource Conservation District Reports and Maps See also List of watercourses in the San Francisco Bay Area	located in the administrative territorial entity	{ "answer_start": [ 74 ], "text": [ "California" ] }
Pescadero Creek is a major stream in Santa Cruz and San Mateo counties in California, United States. At 26.6 miles (42.8 km), it is the longest stream in San Mateo County and flows all year from springs in the Santa Cruz Mountains. Its source is at 1,880 feet (570 m) above sea level on the western edge of Castle Rock State Park, with additional headwaters in Portola Redwoods State Park, and its course traverses Pescadero Creek County Park and San Mateo County Memorial Park before entering Pescadero Marsh Natural Preserve at Pescadero State Beach and thence to the Pacific Ocean 14.4 miles (23 km) south of Half Moon Bay. History Pescadero is Spanish for "fishing place". In early Mexican land grants or disueños, John Gilroy stated "The Castros, I and an Indian gave it that name in 1814, being a place where we used to catch salmon."Arroyo del Pescadero appears on the disueños of the 1830s. The 1860s' Coast Survey called it the Pescador River. Spanish-speaking people founded the town of Pescadero, California in 1856.The pre-European Pescadero watershed was occupied by the Ohlone. The Quirostes controlled the area from Bean Hollow Creek southward to Año Nuevo Creek and inland to Butano Ridge. The Oljon controlled from the lower San Gregorio Creek drainage southward to Bean Hollow Creek, including the lower Pescadero and Butano drainages. The Cotogen held the land in and around Purisima Creek. When the Portolà Expedition traveled on horseback along the immediate coast on October 24, 1769, Padre Juan Crespí wrote, "Only in the watercourses are any trees to be seen; elsewhere we saw nothing but grass, and that was burned." The Ohlone managed the land with the most effective tool they had, fire.The Santa Cruz Lumber Company built a sawmill at Saratoga Gap in 1923. The company formed a log pond by building a wooden dam in the creek, and the sawmill was built over the creek downstream of the log pond. The sawmill employed fifty to eighty men manufacturing sixty-thousand board foot of redwood and Douglas fir lumber daily. A forest railway was extended more than 7 miles (11 km) up Pescadero Creek to bring logs down to the sawmill after loggers had felled all trees close enough to be winched to the mill with cables. Railway operations began when the company purchased a 2-truck Shay locomotive (Lima Locomotive Works number 2461) from the San Joaquin and Eastern Railroad in 1930 and continued until the railroad grade was converted to a truck road in 1950. The sawmill ceased operations in 1972.Farmers began building levees and drained small areas of the marsh by the late 1920s. Substantial levee building and conversion of marshlands to agriculture occurred during the 1930s, and continued through the early 1960s. The State began acquiring land in the 1960s. In the early 1960s local farmers used a dragline to remove sediment from Butano Creek channel below Pescadero Bridge for several thousand feet down stream. The sediment removed was used to build a 6,000 foot levee on the west side of Butano Creek. Other levees were built to keep salt water out of agricultural fields. California Department of Fish and Game (DFG) required the dragline practice to stop following the introduction of new fish protection laws in 1963.The Highway One bridge was rebuilt (1989–90) with fewer supports and closer to the ocean to minimize effects on the stream and lagoon; the original bridge had been built in the early 1940s. Ecology Intensive logging and watershed development, also beginning in the late 1920s or early 1930s, has dramatically increased sedimentation in Butano and Pescadero creeks. Both streams are listed under the federal Clean Water Act as impaired water bodies for sediment. Concerns about agricultural pesticide runoff into the marsh prompted a report prepared by DFG. Jong confirmed eutrophic (high nutrient) conditions in the marsh and found that algae blooms raise dissolve oxygen (DO) levels to saturation during the day and deplete levels during night respiration. Jong speculated that the low night DO could result in fish kills. The DFG study found levels of pesticides potentially toxic to fish in the sediment. In the mid-1980s the west bank levee of Butano Creek was breached about 50 feet downstream of Pescadero Road Bridge in order to reduce flood flows down the Butano Creek channel in the marsh. Breaches in other levees of the North Butano Marsh were also made to improve circulation.Historically, both Pescadero Creek and Butano Creek, as well as several tributary streams, supported runs of steelhead trout (Oncorhynchus mykiss) and coho salmon (Oncorhynchus kisutch). Steelhead are still present, but there have been only sparse reports of coho in the watershed in recent years. Before logging removed much of the dense forest cover of this area in the middle of the 20th century, these streams were shaded, with frequent, stable pools created by fallen trees, bedrock outcrops, and boulders, and an abundant, if not steady, supply of gravel. With cool stream temperatures and reliable flows through the summer, they provided excellent habitat for salmon and trout, and both Pescadero Creek and Butano Creek were renowned sports fishing streams for vacationing San Franciscans in the late 19th century. According to a study by Professor Jerry Smith of San Jose State University, estimates in 1985 showed that 10,000 steelhead trout were rearing in the lagoon. As of 2008, 750 steelhead were counted in the same area. With the exception of a few juvenile coho observed in Peters Creek in 1999, salmon have been absent from the watershed until a 2003 release of 17,000 hatchery-raised coho smolts in Pescadero Creek. Very few of these coho have returned to the creek. In spring 2015, biologists discovered three coho salmon (with tags from the nearby Scott Creek hatchery) spawning in Pescadero Creek.California Golden Beaver (Castor canadensis subauratus) were re-introduced to Pescadero Creek around 1937-1938 by the DFG after near extinction in California in the early twentieth century. The beavers continue to thrive and although concerns about flooding related to beaver dams occurs, there is evidence that beaver in the lower channel in the 1950s reduced sediment movement through the system, especially since the late 1980s. Beaver improve salmonid abundance and size as their beaver ponds recharge the water table which, in turn, replenishes stream flows in the dry season and by providing ideal over-summering habitat. Contrary to popular myth, most beaver dams do not pose barriers to trout and salmon migration, although they may be restricted seasonally during periods of low stream flows. An extensive review recently proved that beaver were historically native to all of California except the most arid deserts, including coastal California. Beaver sign (Castor canadensis) was recently documented in the newly restored Butano Creek channel just above the Pescadero lagoon in September, 2022 (See photo). Pescadero Marsh Located at the confluence of Pescadero and Butano Creeks, the area known as Pescadero Marsh has for decades been a thriving habitat for both migratory and native wildlife. Besides being a refuge and nesting ground for wintering waterfowl, the marsh is a critical spawning area and nursery for coho salmon, steelhead trout, tidewater goby, and many other threatened or endangered fish, amphibian, and reptile species. Since 1995, annual fish "die-offs" of hundreds of juvenile fish, crabs, and other species occur in the late fall when the sandbar barrier between the lagoon and the ocean is breached. As water levels fluctuate, many species are cut off from supportive habitat, and the entire eco-system degrades. Since 1998 concerned citizens and other wildlife agencies have repeatedly asked California State Parks to take immediate corrective action. The Parks Department has failed to respond, and has instead moved to request further studies. Meanwhile, native species populations in the marsh have reached critically low levels. The Pescadero Lagoon Science Panel was established in 2013 to provide independent scientific expertise in support of management decisions and possible restoration actions for Pescadero marsh and lagoon. Steelhead restoration A federal project to revive the steelhead trout population showed success in 2012, and may be continued in 2013. Watershed The Pescadero-Butano watershed is the largest coastal watershed between the Golden Gate and the San Lorenzo River. The watershed's two principal streams, Pescadero Creek and Butano Creek, which have their confluence in Pescadero Marsh, drain 81 square miles (210 km2) of the Santa Cruz Mountains. Peters Creek in Portola Redwoods State Park, Oil Creek, Slate Creek and Butano Creek are the largest of many tributaries of Pescadero Creek. Tributaries Butano Creek Bradley Creek Chandler Gulch Honsinger Creek Windmill Gulch Big Chicken Hollow Little Chicken Hollow Newell Gulch Roy Gulch Blomquist Creek Peterson Creek Hoffman Creek McCormick Creek Harwood Creek Dark Gulch Keyston Creek Carriger Creek Rhododendron Creek Tarwater Creek Peters Creek Evans Creek Bear Creek Lambert Creek Fall Creek Iverson Creek Slate Creek Oil Creek Little Boulder Creek Waterman Creek References External links U.S. Geological Survey Geographic Names Information System: Pescadero Creek Pescadero-Butano Watershed Sediment and Habitat Management Plan Pescadero Marsh Annotated Bibliography at UC Berkeley San Mateo County Resource Conservation District Reports and Maps See also List of watercourses in the San Francisco Bay Area	mouth of the watercourse	{ "answer_start": [ 570 ], "text": [ "Pacific Ocean" ] }
Pescadero Creek is a major stream in Santa Cruz and San Mateo counties in California, United States. At 26.6 miles (42.8 km), it is the longest stream in San Mateo County and flows all year from springs in the Santa Cruz Mountains. Its source is at 1,880 feet (570 m) above sea level on the western edge of Castle Rock State Park, with additional headwaters in Portola Redwoods State Park, and its course traverses Pescadero Creek County Park and San Mateo County Memorial Park before entering Pescadero Marsh Natural Preserve at Pescadero State Beach and thence to the Pacific Ocean 14.4 miles (23 km) south of Half Moon Bay. History Pescadero is Spanish for "fishing place". In early Mexican land grants or disueños, John Gilroy stated "The Castros, I and an Indian gave it that name in 1814, being a place where we used to catch salmon."Arroyo del Pescadero appears on the disueños of the 1830s. The 1860s' Coast Survey called it the Pescador River. Spanish-speaking people founded the town of Pescadero, California in 1856.The pre-European Pescadero watershed was occupied by the Ohlone. The Quirostes controlled the area from Bean Hollow Creek southward to Año Nuevo Creek and inland to Butano Ridge. The Oljon controlled from the lower San Gregorio Creek drainage southward to Bean Hollow Creek, including the lower Pescadero and Butano drainages. The Cotogen held the land in and around Purisima Creek. When the Portolà Expedition traveled on horseback along the immediate coast on October 24, 1769, Padre Juan Crespí wrote, "Only in the watercourses are any trees to be seen; elsewhere we saw nothing but grass, and that was burned." The Ohlone managed the land with the most effective tool they had, fire.The Santa Cruz Lumber Company built a sawmill at Saratoga Gap in 1923. The company formed a log pond by building a wooden dam in the creek, and the sawmill was built over the creek downstream of the log pond. The sawmill employed fifty to eighty men manufacturing sixty-thousand board foot of redwood and Douglas fir lumber daily. A forest railway was extended more than 7 miles (11 km) up Pescadero Creek to bring logs down to the sawmill after loggers had felled all trees close enough to be winched to the mill with cables. Railway operations began when the company purchased a 2-truck Shay locomotive (Lima Locomotive Works number 2461) from the San Joaquin and Eastern Railroad in 1930 and continued until the railroad grade was converted to a truck road in 1950. The sawmill ceased operations in 1972.Farmers began building levees and drained small areas of the marsh by the late 1920s. Substantial levee building and conversion of marshlands to agriculture occurred during the 1930s, and continued through the early 1960s. The State began acquiring land in the 1960s. In the early 1960s local farmers used a dragline to remove sediment from Butano Creek channel below Pescadero Bridge for several thousand feet down stream. The sediment removed was used to build a 6,000 foot levee on the west side of Butano Creek. Other levees were built to keep salt water out of agricultural fields. California Department of Fish and Game (DFG) required the dragline practice to stop following the introduction of new fish protection laws in 1963.The Highway One bridge was rebuilt (1989–90) with fewer supports and closer to the ocean to minimize effects on the stream and lagoon; the original bridge had been built in the early 1940s. Ecology Intensive logging and watershed development, also beginning in the late 1920s or early 1930s, has dramatically increased sedimentation in Butano and Pescadero creeks. Both streams are listed under the federal Clean Water Act as impaired water bodies for sediment. Concerns about agricultural pesticide runoff into the marsh prompted a report prepared by DFG. Jong confirmed eutrophic (high nutrient) conditions in the marsh and found that algae blooms raise dissolve oxygen (DO) levels to saturation during the day and deplete levels during night respiration. Jong speculated that the low night DO could result in fish kills. The DFG study found levels of pesticides potentially toxic to fish in the sediment. In the mid-1980s the west bank levee of Butano Creek was breached about 50 feet downstream of Pescadero Road Bridge in order to reduce flood flows down the Butano Creek channel in the marsh. Breaches in other levees of the North Butano Marsh were also made to improve circulation.Historically, both Pescadero Creek and Butano Creek, as well as several tributary streams, supported runs of steelhead trout (Oncorhynchus mykiss) and coho salmon (Oncorhynchus kisutch). Steelhead are still present, but there have been only sparse reports of coho in the watershed in recent years. Before logging removed much of the dense forest cover of this area in the middle of the 20th century, these streams were shaded, with frequent, stable pools created by fallen trees, bedrock outcrops, and boulders, and an abundant, if not steady, supply of gravel. With cool stream temperatures and reliable flows through the summer, they provided excellent habitat for salmon and trout, and both Pescadero Creek and Butano Creek were renowned sports fishing streams for vacationing San Franciscans in the late 19th century. According to a study by Professor Jerry Smith of San Jose State University, estimates in 1985 showed that 10,000 steelhead trout were rearing in the lagoon. As of 2008, 750 steelhead were counted in the same area. With the exception of a few juvenile coho observed in Peters Creek in 1999, salmon have been absent from the watershed until a 2003 release of 17,000 hatchery-raised coho smolts in Pescadero Creek. Very few of these coho have returned to the creek. In spring 2015, biologists discovered three coho salmon (with tags from the nearby Scott Creek hatchery) spawning in Pescadero Creek.California Golden Beaver (Castor canadensis subauratus) were re-introduced to Pescadero Creek around 1937-1938 by the DFG after near extinction in California in the early twentieth century. The beavers continue to thrive and although concerns about flooding related to beaver dams occurs, there is evidence that beaver in the lower channel in the 1950s reduced sediment movement through the system, especially since the late 1980s. Beaver improve salmonid abundance and size as their beaver ponds recharge the water table which, in turn, replenishes stream flows in the dry season and by providing ideal over-summering habitat. Contrary to popular myth, most beaver dams do not pose barriers to trout and salmon migration, although they may be restricted seasonally during periods of low stream flows. An extensive review recently proved that beaver were historically native to all of California except the most arid deserts, including coastal California. Beaver sign (Castor canadensis) was recently documented in the newly restored Butano Creek channel just above the Pescadero lagoon in September, 2022 (See photo). Pescadero Marsh Located at the confluence of Pescadero and Butano Creeks, the area known as Pescadero Marsh has for decades been a thriving habitat for both migratory and native wildlife. Besides being a refuge and nesting ground for wintering waterfowl, the marsh is a critical spawning area and nursery for coho salmon, steelhead trout, tidewater goby, and many other threatened or endangered fish, amphibian, and reptile species. Since 1995, annual fish "die-offs" of hundreds of juvenile fish, crabs, and other species occur in the late fall when the sandbar barrier between the lagoon and the ocean is breached. As water levels fluctuate, many species are cut off from supportive habitat, and the entire eco-system degrades. Since 1998 concerned citizens and other wildlife agencies have repeatedly asked California State Parks to take immediate corrective action. The Parks Department has failed to respond, and has instead moved to request further studies. Meanwhile, native species populations in the marsh have reached critically low levels. The Pescadero Lagoon Science Panel was established in 2013 to provide independent scientific expertise in support of management decisions and possible restoration actions for Pescadero marsh and lagoon. Steelhead restoration A federal project to revive the steelhead trout population showed success in 2012, and may be continued in 2013. Watershed The Pescadero-Butano watershed is the largest coastal watershed between the Golden Gate and the San Lorenzo River. The watershed's two principal streams, Pescadero Creek and Butano Creek, which have their confluence in Pescadero Marsh, drain 81 square miles (210 km2) of the Santa Cruz Mountains. Peters Creek in Portola Redwoods State Park, Oil Creek, Slate Creek and Butano Creek are the largest of many tributaries of Pescadero Creek. Tributaries Butano Creek Bradley Creek Chandler Gulch Honsinger Creek Windmill Gulch Big Chicken Hollow Little Chicken Hollow Newell Gulch Roy Gulch Blomquist Creek Peterson Creek Hoffman Creek McCormick Creek Harwood Creek Dark Gulch Keyston Creek Carriger Creek Rhododendron Creek Tarwater Creek Peters Creek Evans Creek Bear Creek Lambert Creek Fall Creek Iverson Creek Slate Creek Oil Creek Little Boulder Creek Waterman Creek References External links U.S. Geological Survey Geographic Names Information System: Pescadero Creek Pescadero-Butano Watershed Sediment and Habitat Management Plan Pescadero Marsh Annotated Bibliography at UC Berkeley San Mateo County Resource Conservation District Reports and Maps See also List of watercourses in the San Francisco Bay Area	tributary	{ "answer_start": [ 8850 ], "text": [ "Bradley Creek" ] }
Sybra rouyeri is a species of beetle in the family Cerambycidae. It was described by Pic in 1938. It is known from Borneo and Java. == References ==	taxon rank	{ "answer_start": [ 19 ], "text": [ "species" ] }
Sybra rouyeri is a species of beetle in the family Cerambycidae. It was described by Pic in 1938. It is known from Borneo and Java. == References ==	parent taxon	{ "answer_start": [ 0 ], "text": [ "Sybra" ] }
Sybra rouyeri is a species of beetle in the family Cerambycidae. It was described by Pic in 1938. It is known from Borneo and Java. == References ==	taxon name	{ "answer_start": [ 0 ], "text": [ "Sybra rouyeri" ] }
Pavel Kuzmich (born 16 June 1988 in Krasnoyarsk) is a Russian luger who has competed since 2009. His best World Cup finish was 16th in the men's doubles event at Igls on 28 November 2009. External links FIL-Luge profile	place of birth	{ "answer_start": [ 36 ], "text": [ "Krasnoyarsk" ] }
Pavel Kuzmich (born 16 June 1988 in Krasnoyarsk) is a Russian luger who has competed since 2009. His best World Cup finish was 16th in the men's doubles event at Igls on 28 November 2009. External links FIL-Luge profile	country of citizenship	{ "answer_start": [ 54 ], "text": [ "Russia" ] }
Pavel Kuzmich (born 16 June 1988 in Krasnoyarsk) is a Russian luger who has competed since 2009. His best World Cup finish was 16th in the men's doubles event at Igls on 28 November 2009. External links FIL-Luge profile	occupation	{ "answer_start": [ 62 ], "text": [ "luger" ] }
Pavel Kuzmich (born 16 June 1988 in Krasnoyarsk) is a Russian luger who has competed since 2009. His best World Cup finish was 16th in the men's doubles event at Igls on 28 November 2009. External links FIL-Luge profile	sport	{ "answer_start": [ 62 ], "text": [ "luge" ] }
Pavel Kuzmich (born 16 June 1988 in Krasnoyarsk) is a Russian luger who has competed since 2009. His best World Cup finish was 16th in the men's doubles event at Igls on 28 November 2009. External links FIL-Luge profile	family name	{ "answer_start": [ 6 ], "text": [ "Kuzmich" ] }
Pavel Kuzmich (born 16 June 1988 in Krasnoyarsk) is a Russian luger who has competed since 2009. His best World Cup finish was 16th in the men's doubles event at Igls on 28 November 2009. External links FIL-Luge profile	given name	{ "answer_start": [ 0 ], "text": [ "Pavel" ] }
Pavel Kuzmich (born 16 June 1988 in Krasnoyarsk) is a Russian luger who has competed since 2009. His best World Cup finish was 16th in the men's doubles event at Igls on 28 November 2009. External links FIL-Luge profile	languages spoken, written or signed	{ "answer_start": [ 54 ], "text": [ "Russian" ] }
The Eocene (IPA: EE-ə-seen, EE-oh-) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name Eocene comes from the Ancient Greek ἠώς (ēṓs, "dawn") and καινός (kainós, "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the Grande Coupure (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the epoch are well identified, though their exact dates are slightly uncertain. Etymology The term "Eocene" is derived from Ancient Greek ἠώς eos meaning "dawn", and καινός kainos meaning "new" or "recent", as the epoch saw the dawn of recent, or modern, life. Scottish geologist Charles Lyell (ignoring the Quaternary) had divided the Tertiary Epoch into the Eocene, Miocene, Pliocene, and New Pliocene (Holocene) Periods in 1833. British geologist John Phillips had proposed the Cenozoic in 1840 in place of the Tertiary, and Austrian paleontologist Moritz Hörnes had introduced the Paleogene for the Eocene and Neogene for the Miocene and Pliocene in 1853. After decades of inconsistent usage, the newly formed International Commission on Stratigraphy (ICS), in 1969, standardized stratigraphy based on the prevailing opinions in Europe: the Cenozoic Era subdivided into the Tertiary and Quaternary sub-eras, and the Tertiary subdivided into the Paleogene and Neogene periods. In 1978, the Paleogene was officially defined as the Paleocene, Eocene, and Oligocene epochs; and the Neogene as the Miocene and Pliocene epochs. In 1989, Tertiary and Quaternary were removed from the time scale due to the arbitrary nature of their boundary, but Quaternary was reinstated in 2009. Geology Boundaries The beginning of the Eocene is marked by the Paleocene–Eocene Thermal Maximum, a short period of intense warming and ocean acidification brought about by the release of carbon en masse into the atmosphere and ocean systems, which led to a mass extinction of 30–50% of benthic foraminifera–single-celled species which are used as bioindicators of the health of a marine ecosystem—one of the largest in the Cenozoic. This event happened around 55.8 mya, and was one of the most significant periods of global change during the Cenozoic.The end of the Eocene was marked by the Eocene–Oligocene extinction event, also known as the Grande Coupure. Stratigraphy The Eocene is conventionally divided into early (56–47.8 Ma), middle (47.8–38 Ma), and late (38–33.9 Ma) subdivisions. The corresponding rocks are referred to as lower, middle, and upper Eocene. The Ypresian Stage constitutes the lower, the Priabonian Stage the upper; and the Lutetian and Bartonian stages are united as the middle Eocene. Palaeogeography and tectonics During the Eocene, the continents continued to drift toward their present positions. At the beginning of the period, Australia and Antarctica remained connected, and warm equatorial currents may have mixed with colder Antarctic waters, distributing the heat around the planet and keeping global temperatures high. When Australia split from the southern continent around 45 Ma, the warm equatorial currents were routed away from Antarctica. An isolated cold water channel developed between the two continents. However, modeling results call into question the thermal isolation model for late Eocene cooling, and decreasing carbon dioxide levels in the atmosphere may have been more important. Once the Antarctic region began to cool down, the ocean surrounding Antarctica began to freeze, sending cold water and icefloes north and reinforcing the cooling.The northern supercontinent of Laurasia began to fragment, as Europe, Greenland and North America drifted apart.In western North America, the Laramide Orogeny came to an end in the Eocene, and compression was replaced with crustal extension that ultimately gave rise to the Basin and Range Province. Huge lakes formed in the high flat basins among uplifts, resulting in the deposition of the Green River Formation lagerstätte.At about 35 Ma, an asteroid impact on the eastern coast of North America formed the Chesapeake Bay impact crater.In Europe, the Tethys Sea finally disappeared, while the uplift of the Alps isolated its final remnant, the Mediterranean, and created another shallow sea with island archipelagos to the north. Though the North Atlantic was opening, a land connection appears to have remained between North America and Europe since the faunas of the two regions are very similar.Eurasia was separated in three different landmasses 50 Ma; Western Europe, Balkanatolia and Asia. About 40 Ma, Balkanatolia and Asia were connected, while Europe was connected 34 Ma.India collided with Asia, folding to initiate formation of the Himalayas. India collided with the Kohistan–Ladakh Arc around 50.2 Ma and with Karakoram around 40.4 Ma, with the final collision between Asia and India occurring ~40 Ma. Climate The Eocene Epoch contained a wide variety of different climate conditions that includes the warmest climate in the Cenozoic Era, and arguably the warmest time interval since the Permian-Triassic mass extinction and Early Triassic, and ends in an icehouse climate. The evolution of the Eocene climate began with warming after the end of the Paleocene–Eocene Thermal Maximum (PETM) at 56 Ma to a maximum during the Eocene Optimum at around 49 Ma. Recent study show elevation-dependent temperature changes during the Eocene hothouse. During this period of time, little to no ice was present on Earth with a smaller difference in temperature from the equator to the poles. Because of this the maximum sea level was 150 meters higher than current levels. Following the maximum was a descent into an icehouse climate from the Eocene Optimum to the Eocene-Oligocene transition at 34 Ma. During this decrease, ice began to reappear at the poles, and the Eocene-Oligocene transition is the period of time where the Antarctic ice sheet began to rapidly expand. Early Eocene Greenhouse gases, in particular carbon dioxide and methane, played a significant role during the Eocene in controlling the surface temperature. The end of the PETM was met with very large sequestration of carbon dioxide into the forms of methane clathrate, coal, and crude oil at the bottom of the Arctic Ocean, that reduced the atmospheric carbon dioxide. This event was similar in magnitude to the massive release of greenhouse gasses at the beginning of the PETM, and it is hypothesized that the sequestration was mainly due to organic carbon burial and weathering of silicates. For the early Eocene there is much discussion on how much carbon dioxide was in the atmosphere. This is due to numerous proxies representing different atmospheric carbon dioxide content. For example, diverse geochemical and paleontological proxies indicate that at the maximum of global warmth the atmospheric carbon dioxide values were at 700–900 ppm while other proxies such as pedogenic (soil building) carbonate and marine boron isotopes indicate large changes of carbon dioxide of over 2,000 ppm over periods of time of less than 1 million years. Sources for this large influx of carbon dioxide could be attributed to volcanic out-gassing due to North Atlantic rifting or oxidation of methane stored in large reservoirs deposited from the PETM event in the sea floor or wetland environments. For contrast, today the carbon dioxide levels are at 400 ppm or 0.04%. At about the beginning of the Eocene Epoch (55.8–33.9 Ma) the amount of oxygen in the earth's atmosphere more or less doubled.During the early Eocene, methane was another greenhouse gas that had a drastic effect on the climate. The warming effect of one ton of methane dimensions unspecified is approximately 30 times the warming effect of one ton of carbon on a 100-year scale (i.e., methane has a global warming potential of 29.8±11). Most of the methane released to the atmosphere during this period of time would have been from wetlands, swamps, and forests. The atmospheric methane concentration today is 0.000179% or 1.79 ppmv. As a result of the warmer climate and the sea level rise associated with the early Eocene, more wetlands, more forests, and more coal deposits would have been available for methane release. If we compare the early Eocene production of methane to current levels of atmospheric methane, the early Eocene would have produced triple the amount of methane. The warm temperatures during the early Eocene could have increased methane production rates, and methane that is released into the atmosphere would in turn warm the troposphere, cool the stratosphere, and produce water vapor and carbon dioxide through oxidation. Biogenic production of methane produces carbon dioxide and water vapor along with the methane, as well as yielding infrared radiation. The breakdown of methane in an atmosphere containing oxygen produces carbon monoxide, water vapor and infrared radiation. The carbon monoxide is not stable, so it eventually becomes carbon dioxide and in doing so releases yet more infrared radiation. Water vapor traps more infrared than does carbon dioxide. Hyperthermals through the early Eocene During the warming in the early Eocene between 55 and 52 Ma, there were a series of short-term changes of carbon isotope composition in the ocean. These isotope changes occurred due to the release of carbon from the ocean into the atmosphere that led to a temperature increase of 4–8 °C (7.2–14.4 °F) at the surface of the ocean. These hyperthermals led to increased perturbations in planktonic and benthic foraminifera, with a higher rate of sedimentation as a consequence of the warmer temperatures. Recent analysis of and research into these hyperthermals in the early Eocene has led to hypotheses that the hyperthermals are based on orbital parameters, in particular eccentricity and obliquity. The hyperthermals in the early Eocene, notably the Palaeocene–Eocene Thermal Maximum (PETM), the Eocene Thermal Maximum 2 (ETM2), and the Eocene Thermal Maximum 3 (ETM3), were analyzed and found that orbital control may have had a role in triggering the ETM2 and ETM3. Equable climate problem One of the unique features of the Eocene's climate as mentioned before was the equable and homogeneous climate that existed in the early parts of the Eocene. A multitude of proxies support the presence of a warmer equable climate being present during this period of time. A few of these proxies include the presence of fossils native to warm climates, such as crocodiles, located in the higher latitudes, the presence in the high latitudes of frost-intolerant flora such as palm trees which cannot survive during sustained freezes, and fossils of snakes found in the tropics that would require much higher average temperatures to sustain them. TEX86 BAYSPAR measurements indicate extremely high sea surface temperatures of 40 °C (104 °F) to 45 °C (113 °F) at low latitudes, although clumped isotope analyses point to a maximum low latitude sea surface temperature of 36.3 °C (97.3 °F) ± 1.9 °C (35.4 °F) during the Early Eocene Climatic Optimum. Relative to present-day values, bottom water temperatures are 10 °C (18 °F) higher according to isotope proxies. With these bottom water temperatures, temperatures in areas where deep water forms near the poles are unable to be much cooler than the bottom water temperatures.An issue arises, however, when trying to model the Eocene and reproduce the results that are found with the proxy data. Using all different ranges of greenhouse gasses that occurred during the early Eocene, models were unable to produce the warming that was found at the poles and the reduced seasonality that occurs with winters at the poles being substantially warmer. The models, while accurately predicting the tropics, tend to produce significantly cooler temperatures of up to 20 °C (36 °F) colder than the actual determined temperature at the poles. This error has been classified as the "equable climate problem". To solve this problem, the solution would involve finding a process to warm the poles without warming the tropics. Some hypotheses and tests which attempt to find the process are listed below. Large lakes Due to the nature of water as opposed to land, less temperature variability would be present if a large body of water is also present. In an attempt to try to mitigate the cooling polar temperatures, large lakes were proposed to mitigate seasonal climate changes. To replicate this case, a lake was inserted into North America and a climate model was run using varying carbon dioxide levels. The model runs concluded that while the lake did reduce the seasonality of the region greater than just an increase in carbon dioxide, the addition of a large lake was unable to reduce the seasonality to the levels shown by the floral and faunal data. Ocean heat transport The transport of heat from the tropics to the poles, much like how ocean heat transport functions in modern times, was considered a possibility for the increased temperature and reduced seasonality for the poles. With the increased sea surface temperatures and the increased temperature of the deep ocean water during the early Eocene, one common hypothesis was that due to these increases there would be a greater transport of heat from the tropics to the poles. Simulating these differences, the models produced lower heat transport due to the lower temperature gradients and were unsuccessful in producing an equable climate from only ocean heat transport. Orbital parameters While typically seen as a control on ice growth and seasonality, the orbital parameters were theorized as a possible control on continental temperatures and seasonality. Simulating the Eocene by using an ice free planet, eccentricity, obliquity, and precession were modified in different model runs to determine all the possible different scenarios that could occur and their effects on temperature. One particular case led to warmer winters and cooler summer by up to 30% in the North American continent, and it reduced the seasonal variation of temperature by up to 75%. While orbital parameters did not produce the warming at the poles, the parameters did show a great effect on seasonality and needed to be considered. Polar stratospheric clouds Another method considered for producing the warm polar temperatures were polar stratospheric clouds. Polar stratospheric clouds are clouds that occur in the lower stratosphere at very low temperatures. Polar stratospheric clouds have a great impact on radiative forcing. Due to their minimal albedo properties and their optical thickness, polar stratospheric clouds act similar to a greenhouse gas and traps outgoing longwave radiation. Different types of polar stratospheric clouds occur in the atmosphere: polar stratospheric clouds that are created due to interactions with nitric or sulfuric acid and water (Type I) or polar stratospheric clouds that are created with only water ice (Type II).Methane is an important factor in the creation of the primary Type II polar stratospheric clouds that were created in the early Eocene. Since water vapor is the only supporting substance used in Type II polar stratospheric clouds, the presence of water vapor in the lower stratosphere is necessary where in most situations the presence of water vapor in the lower stratosphere is rare. When methane is oxidized, a significant amount of water vapor is released. Another requirement for polar stratospheric clouds is cold temperatures to ensure condensation and cloud production. Polar stratospheric cloud production, since it requires the cold temperatures, is usually limited to nighttime and winter conditions. With this combination of wetter and colder conditions in the lower stratosphere, polar stratospheric clouds could have formed over wide areas in Polar Regions.To test the polar stratospheric clouds effects on the Eocene climate, models were run comparing the effects of polar stratospheric clouds at the poles to an increase in atmospheric carbon dioxide. The polar stratospheric clouds had a warming effect on the poles, increasing temperatures by up to 20 °C in the winter months. A multitude of feedbacks also occurred in the models due to the polar stratospheric clouds' presence. Any ice growth was slowed immensely and would lead to any present ice melting. Only the poles were affected with the change in temperature and the tropics were unaffected, which with an increase in atmospheric carbon dioxide would also cause the tropics to increase in temperature. Due to the warming of the troposphere from the increased greenhouse effect of the polar stratospheric clouds, the stratosphere would cool and would potentially increase the amount of polar stratospheric clouds. While the polar stratospheric clouds could explain the reduction of the equator to pole temperature gradient and the increased temperatures at the poles during the early Eocene, there are a few drawbacks to maintaining polar stratospheric clouds for an extended period of time. Separate model runs were used to determine the sustainability of the polar stratospheric clouds. It was determined that in order to maintain the lower stratospheric water vapor, methane would need to be continually released and sustained. In addition, the amounts of ice and condensation nuclei would need to be high in order for the polar stratospheric cloud to sustain itself and eventually expand. Middle Eocene The Eocene is not only known for containing the warmest period during the Cenozoic; it also marked the decline into an icehouse climate and the rapid expansion of the Antarctic ice sheet. The transition from a warming climate into a cooling climate began at around 49 Ma. Isotopes of carbon and oxygen indicate a shift to a global cooling climate. The cause of the cooling has been attributed to a significant decrease of >2,000 ppm in atmospheric carbon dioxide concentrations. One proposed cause of the reduction in carbon dioxide during the warming to cooling transition was the azolla event. With the equable climate during the early Eocene, warm temperatures in the arctic allowed for the growth of azolla, which is a floating aquatic fern, on the Arctic Ocean. The significantly high amounts of carbon dioxide also acted to facilitate azolla blooms across the Arctic Ocean. Compared to current carbon dioxide levels, these azolla grew rapidly in the enhanced carbon dioxide levels found in the early Eocene. The isolation of the Arctic Ocean, evidenced by euxinia that occurred at this time, led to stagnant waters and as the azolla sank to the sea floor, they became part of the sediments on the seabed and effectively sequestered the carbon by locking it out of the atmosphere for good. The ability for the azolla to sequester carbon is exceptional, and the enhanced burial of azolla could have had a significant effect on the world atmospheric carbon content and may have been the event to begin the transition into an ice house climate. The azolla event could have led to a draw down of atmospheric carbon dioxide of up to 470 ppm. Assuming the carbon dioxide concentrations were at 900 ppmv prior to the Azolla Event they would have dropped to 430 ppmv, or 30 ppmv more than they are today, after the Azolla Event. This cooling trend at the end of the Early Eocene Climatic Optimum has also been proposed to have been caused by increased siliceous plankton productivity and marine carbon burial, which also helped draw carbon dioxide out of the atmosphere. Cooling after this event continued due to continual decrease in atmospheric carbon dioxide from organic productivity and weathering from mountain building.Global cooling continued until there was a major reversal from cooling to warming in the Bartonian. This warming event, signifying a sudden and temporary reversal of the cooling conditions, is known as the Middle Eocene Climatic Optimum (MECO). At around 41.5 Ma, stable isotopic analysis of samples from Southern Ocean drilling sites indicated a warming event for 600,000 years. A similar shift in carbon isotopes is known from the Northern Hemisphere in the Scaglia Limestones of Italy. Oxygen isotope analysis showed a large negative change in the proportion of heavier oxygen isotopes to lighter oxygen isotopes, which indicates an increase in global temperatures. The warming is considered to be primarily due to carbon dioxide increases, because carbon isotope signatures rule out major methane release during this short-term warming. A sharp increase in atmospheric carbon dioxide was observed with a maximum of 4,000 ppm: the highest amount of atmospheric carbon dioxide detected during the Eocene. Other studies suggest a more modest rise in carbon dioxide levels. The increase in atmospheric carbon dioxide has also been hypothesised to have been driven by increased seafloor spreading rates and metamorphic decarbonation reactions between Australia and Antarctica and increased amounts of volcanism in the region. One possible cause of atmospheric carbon dioxide increase could have been a sudden increase due to metamorphic release due to continental drift and collision of India with Asia and the resulting formation of the Himalayas; however, data on the exact timing of metamorphic release of atmospheric carbon dioxide is not well resolved in the data. Recent studies have mentioned, however, that the removal of the ocean between Asia and India could have released significant amounts of carbon dioxide. Another hypothesis still implicates a diminished negative feedback of silicate weathering as a result of continental rocks having become less weatherable during the warm Early and Middle Eocene, allowing volcanically released carbon dioxide to persist in the atmosphere for longer. Yet another explanation hypothesises that MECO warming was caused by the simultaneous occurrence of minima in both the 400 kyr and 2.4 Myr eccentricity cycles. During the MECO, sea surface temperatures in the Tethys Ocean jumped to 32-36 °C, and Tethyan seawater became more dysoxic. A decline in carbonate accumulation at ocean depths of greater than three kilometres took place synchronously with the peak of the MECO, signifying ocean acidification took place in the deep ocean. An abrupt decrease in lakewater salinity in western North America occurred during this warming interval. This warming is short lived, as benthic oxygen isotope records indicate a return to cooling at ~40 Ma. Late Eocene At the end of the Middle Eocene Climatic Optimum, cooling and the carbon dioxide drawdown continued through the late Eocene and into the Eocene–Oligocene transition around 34 Ma. The post-MECO cooling brought with it a major aridification trend in Asia. The cooling during the initial stages of the opening of the Drake Passage ~38.5 Ma was not global, as evidenced by an absence of cooling in the North Atlantic. During the cooling period, benthic oxygen isotopes show the possibility of ice creation and ice increase during this later cooling. The end of the Eocene and beginning of the Oligocene is marked with the massive expansion of area of the Antarctic ice sheet that was a major step into the icehouse climate. Multiple proxies, such as oxygen isotopes and alkenones, indicate that at the Eocene–Oligocene transition, the atmospheric carbon dioxide concentration had decreased to around 750–800 ppm, approximately twice that of present levels. Along with the decrease of atmospheric carbon dioxide reducing the global temperature, orbital factors in ice creation can be seen with 100,000-year and 400,000-year fluctuations in benthic oxygen isotope records. Another major contribution to the expansion of the ice sheet was the creation of the Antarctic Circumpolar Current. The creation of the Antarctic circumpolar current would isolate the cold water around the Antarctic, which would reduce heat transport to the Antarctic along with creating ocean gyres that result in the upwelling of colder bottom waters. The issue with this hypothesis of the consideration of this being a factor for the Eocene-Oligocene transition is the timing of the creation of the circulation is uncertain. For Drake Passage, sediments indicate the opening occurred ~41 Ma while tectonics indicate that this occurred ~32 Ma. Flora During the early-middle Eocene, forests covered most of the Earth including the poles. Tropical forests extended across much of modern Africa, South America, Central America, India, South-east Asia and China. Paratropical forests grew over North America, Europe and Russia, with broad-leafed evergreen and broad-leafed deciduous forests at higher latitudes.Polar forests were quite extensive. Fossils and even preserved remains of trees such as swamp cypress and dawn redwood from the Eocene have been found on Ellesmere Island in the Arctic. Even at that time, Ellesmere Island was only a few degrees in latitude further south than it is today. Fossils of subtropical and even tropical trees and plants from the Eocene also have been found in Greenland and Alaska. Tropical rainforests grew as far north as northern North America and Europe.Palm trees were growing as far north as Alaska and northern Europe during the early Eocene, although they became less abundant as the climate cooled. Dawn redwoods were far more extensive as well.The earliest definitive Eucalyptus fossils were dated from 51.9 Mya, and were found in the Laguna del Hunco deposit in Chubut province in Argentina.Cooling began mid-period, and by the end of the Eocene continental interiors had begun to dry, with forests thinning considerably in some areas. The newly evolved grasses were still confined to river banks and lake shores, and had not yet expanded into plains and savannas.The cooling also brought seasonal changes. Deciduous trees, better able to cope with large temperature changes, began to overtake evergreen tropical species. By the end of the period, deciduous forests covered large parts of the northern continents, including North America, Eurasia and the Arctic, and rainforests held on only in equatorial South America, Africa, India and Australia.Antarctica began the Eocene fringed with a warm temperate to sub-tropical rainforest. Pollen found in Prydz Bay from the Eocene suggest taiga forest existed there. It became much colder as the period progressed; the heat-loving tropical flora was wiped out, and by the beginning of the Oligocene, the continent hosted deciduous forests and vast stretches of tundra. Fauna During the Eocene, plants and marine faunas became quite modern. Many modern bird orders first appeared in the Eocene. The Eocene oceans were warm and teeming with fish and other sea life. Mammals The oldest known fossils of most of the modern mammal orders appear within a brief period during the early Eocene. At the beginning of the Eocene, several new mammal groups arrived in North America. These modern mammals, like artiodactyls, perissodactyls, and primates, had features like long, thin legs, feet, and hands capable of grasping, as well as differentiated teeth adapted for chewing. Dwarf forms reigned. All the members of the new mammal orders were small, under 10 kg; based on comparisons of tooth size, Eocene mammals were only 60% of the size of the primitive Palaeocene mammals that preceded them. They were also smaller than the mammals that followed them. It is assumed that the hot Eocene temperatures favored smaller animals that were better able to manage the heat.Both groups of modern ungulates (hoofed animals) became prevalent because of a major radiation between Europe and North America, along with carnivorous ungulates like Mesonyx. Early forms of many other modern mammalian orders appeared, including horses (most notably the Eohippus), bats, proboscidians (elephants), primates, rodents, and marsupials. Older primitive forms of mammals declined in variety and importance. Important Eocene land fauna fossil remains have been found in western North America, Europe, Patagonia, Egypt, and southeast Asia. Marine fauna are best known from South Asia and the southeast United States.Established megafauna of the Eocene include the Uintatherium, Arsinoitherium, and brontotheres, in which the former two, unlike the latter, did not belong to ungulates but groups that became extinct shortly after their establishments. Large terrestrial mammalian predators began to take form as the terrestrial carnivores like the Hyaenodon and Daphoenus (the earliest lineage of a once-successful predatory family known as bear dogs). Entelodonts meanwhile established themselves as some of the largest omnivores. The first nimravids, including Dinictis, established themselves as amongst the first feliforms to appear. Their groups became highly successful and continued to live past the Eocene. Basilosaurus is a very well-known Eocene whale, but whales as a group had become very diverse during the Eocene, which is when the major transitions from being terrestrial to fully aquatic in cetaceans occurred. The first sirenians were evolving at this time, and would eventually evolve into the extant manatees and dugongs. It is thought that millions of years after the Cretaceous-Paleogene extinction event, brain sizes of mammals now started to increase, "likely driven by a need for greater cognition in increasingly complex environments". Birds Eocene birds include some enigmatic groups with resemblances to modern forms, some of which continued from the Paleocene. Bird taxa of the Eocene include carnivorous psittaciforms, such as Messelasturidae, Halcyornithidae, large flightless forms such as Gastornis and Eleutherornis, long legged falcon Masillaraptor, ancient galliforms such as Gallinuloides, putative rail relatives of the family Songziidae, various pseudotooth birds such as Gigantornis, the ibis relative Rhynchaeites, primitive swifts of the genus Aegialornis, and primitive penguins such as Archaeospheniscus and Inkayacu. Reptiles Reptile fossils from this time, such as fossils of pythons and turtles, are abundant. Insects and arachnids Several rich fossil insect faunas are known from the Eocene, notably the Baltic amber found mainly along the south coast of the Baltic Sea, amber from the Paris Basin, France, the Fur Formation, Denmark, and the Bembridge Marls from the Isle of Wight, England. Insects found in Eocene deposits mostly belong to genera that exist today, though their range has often shifted since the Eocene. For instance the bibionid genus Plecia is common in fossil faunas from presently temperate areas, but only lives in the tropics and subtropics today. Gallery See also Bolca in Italy List of fossil sites (with link directory) London Clay Messel pit in Germany Wadi El Hitan in Egypt Notes References Further reading Ogg, Jim; June, 2004, Overview of Global Boundary Stratotype Sections and Points (GSSP's) Global Stratotype Sections and Points Accessed April 30, 2006. Stanley, Steven M. Earth System History. New York: W.H. Freeman and Company, 1999. ISBN 0-7167-2882-6 External links PaleoMap Project Paleos Eocene page PBS Deep Time: Eocene Eocene and Oligocene Fossils The UPenn Fossil Forest Project, focusing on the Eocene polar forests in Ellesmere Island, Canada Basilosaurus Primitive Eocene Whales Basilosaurus - The plesiosaur that wasn't.... Detailed maps of Tertiary Western North America Map of Eocene Earth Eocene Microfossils: 60+ images of Foraminifera Eocene Epoch. (2011). In Encyclopædia Britannica. Retrieved from Eocene Epoch \| geochronology	title	{ "answer_start": [ 4 ], "text": [ "Eocene" ] }
The Eocene (IPA: EE-ə-seen, EE-oh-) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name Eocene comes from the Ancient Greek ἠώς (ēṓs, "dawn") and καινός (kainós, "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the Grande Coupure (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the epoch are well identified, though their exact dates are slightly uncertain. Etymology The term "Eocene" is derived from Ancient Greek ἠώς eos meaning "dawn", and καινός kainos meaning "new" or "recent", as the epoch saw the dawn of recent, or modern, life. Scottish geologist Charles Lyell (ignoring the Quaternary) had divided the Tertiary Epoch into the Eocene, Miocene, Pliocene, and New Pliocene (Holocene) Periods in 1833. British geologist John Phillips had proposed the Cenozoic in 1840 in place of the Tertiary, and Austrian paleontologist Moritz Hörnes had introduced the Paleogene for the Eocene and Neogene for the Miocene and Pliocene in 1853. After decades of inconsistent usage, the newly formed International Commission on Stratigraphy (ICS), in 1969, standardized stratigraphy based on the prevailing opinions in Europe: the Cenozoic Era subdivided into the Tertiary and Quaternary sub-eras, and the Tertiary subdivided into the Paleogene and Neogene periods. In 1978, the Paleogene was officially defined as the Paleocene, Eocene, and Oligocene epochs; and the Neogene as the Miocene and Pliocene epochs. In 1989, Tertiary and Quaternary were removed from the time scale due to the arbitrary nature of their boundary, but Quaternary was reinstated in 2009. Geology Boundaries The beginning of the Eocene is marked by the Paleocene–Eocene Thermal Maximum, a short period of intense warming and ocean acidification brought about by the release of carbon en masse into the atmosphere and ocean systems, which led to a mass extinction of 30–50% of benthic foraminifera–single-celled species which are used as bioindicators of the health of a marine ecosystem—one of the largest in the Cenozoic. This event happened around 55.8 mya, and was one of the most significant periods of global change during the Cenozoic.The end of the Eocene was marked by the Eocene–Oligocene extinction event, also known as the Grande Coupure. Stratigraphy The Eocene is conventionally divided into early (56–47.8 Ma), middle (47.8–38 Ma), and late (38–33.9 Ma) subdivisions. The corresponding rocks are referred to as lower, middle, and upper Eocene. The Ypresian Stage constitutes the lower, the Priabonian Stage the upper; and the Lutetian and Bartonian stages are united as the middle Eocene. Palaeogeography and tectonics During the Eocene, the continents continued to drift toward their present positions. At the beginning of the period, Australia and Antarctica remained connected, and warm equatorial currents may have mixed with colder Antarctic waters, distributing the heat around the planet and keeping global temperatures high. When Australia split from the southern continent around 45 Ma, the warm equatorial currents were routed away from Antarctica. An isolated cold water channel developed between the two continents. However, modeling results call into question the thermal isolation model for late Eocene cooling, and decreasing carbon dioxide levels in the atmosphere may have been more important. Once the Antarctic region began to cool down, the ocean surrounding Antarctica began to freeze, sending cold water and icefloes north and reinforcing the cooling.The northern supercontinent of Laurasia began to fragment, as Europe, Greenland and North America drifted apart.In western North America, the Laramide Orogeny came to an end in the Eocene, and compression was replaced with crustal extension that ultimately gave rise to the Basin and Range Province. Huge lakes formed in the high flat basins among uplifts, resulting in the deposition of the Green River Formation lagerstätte.At about 35 Ma, an asteroid impact on the eastern coast of North America formed the Chesapeake Bay impact crater.In Europe, the Tethys Sea finally disappeared, while the uplift of the Alps isolated its final remnant, the Mediterranean, and created another shallow sea with island archipelagos to the north. Though the North Atlantic was opening, a land connection appears to have remained between North America and Europe since the faunas of the two regions are very similar.Eurasia was separated in three different landmasses 50 Ma; Western Europe, Balkanatolia and Asia. About 40 Ma, Balkanatolia and Asia were connected, while Europe was connected 34 Ma.India collided with Asia, folding to initiate formation of the Himalayas. India collided with the Kohistan–Ladakh Arc around 50.2 Ma and with Karakoram around 40.4 Ma, with the final collision between Asia and India occurring ~40 Ma. Climate The Eocene Epoch contained a wide variety of different climate conditions that includes the warmest climate in the Cenozoic Era, and arguably the warmest time interval since the Permian-Triassic mass extinction and Early Triassic, and ends in an icehouse climate. The evolution of the Eocene climate began with warming after the end of the Paleocene–Eocene Thermal Maximum (PETM) at 56 Ma to a maximum during the Eocene Optimum at around 49 Ma. Recent study show elevation-dependent temperature changes during the Eocene hothouse. During this period of time, little to no ice was present on Earth with a smaller difference in temperature from the equator to the poles. Because of this the maximum sea level was 150 meters higher than current levels. Following the maximum was a descent into an icehouse climate from the Eocene Optimum to the Eocene-Oligocene transition at 34 Ma. During this decrease, ice began to reappear at the poles, and the Eocene-Oligocene transition is the period of time where the Antarctic ice sheet began to rapidly expand. Early Eocene Greenhouse gases, in particular carbon dioxide and methane, played a significant role during the Eocene in controlling the surface temperature. The end of the PETM was met with very large sequestration of carbon dioxide into the forms of methane clathrate, coal, and crude oil at the bottom of the Arctic Ocean, that reduced the atmospheric carbon dioxide. This event was similar in magnitude to the massive release of greenhouse gasses at the beginning of the PETM, and it is hypothesized that the sequestration was mainly due to organic carbon burial and weathering of silicates. For the early Eocene there is much discussion on how much carbon dioxide was in the atmosphere. This is due to numerous proxies representing different atmospheric carbon dioxide content. For example, diverse geochemical and paleontological proxies indicate that at the maximum of global warmth the atmospheric carbon dioxide values were at 700–900 ppm while other proxies such as pedogenic (soil building) carbonate and marine boron isotopes indicate large changes of carbon dioxide of over 2,000 ppm over periods of time of less than 1 million years. Sources for this large influx of carbon dioxide could be attributed to volcanic out-gassing due to North Atlantic rifting or oxidation of methane stored in large reservoirs deposited from the PETM event in the sea floor or wetland environments. For contrast, today the carbon dioxide levels are at 400 ppm or 0.04%. At about the beginning of the Eocene Epoch (55.8–33.9 Ma) the amount of oxygen in the earth's atmosphere more or less doubled.During the early Eocene, methane was another greenhouse gas that had a drastic effect on the climate. The warming effect of one ton of methane dimensions unspecified is approximately 30 times the warming effect of one ton of carbon on a 100-year scale (i.e., methane has a global warming potential of 29.8±11). Most of the methane released to the atmosphere during this period of time would have been from wetlands, swamps, and forests. The atmospheric methane concentration today is 0.000179% or 1.79 ppmv. As a result of the warmer climate and the sea level rise associated with the early Eocene, more wetlands, more forests, and more coal deposits would have been available for methane release. If we compare the early Eocene production of methane to current levels of atmospheric methane, the early Eocene would have produced triple the amount of methane. The warm temperatures during the early Eocene could have increased methane production rates, and methane that is released into the atmosphere would in turn warm the troposphere, cool the stratosphere, and produce water vapor and carbon dioxide through oxidation. Biogenic production of methane produces carbon dioxide and water vapor along with the methane, as well as yielding infrared radiation. The breakdown of methane in an atmosphere containing oxygen produces carbon monoxide, water vapor and infrared radiation. The carbon monoxide is not stable, so it eventually becomes carbon dioxide and in doing so releases yet more infrared radiation. Water vapor traps more infrared than does carbon dioxide. Hyperthermals through the early Eocene During the warming in the early Eocene between 55 and 52 Ma, there were a series of short-term changes of carbon isotope composition in the ocean. These isotope changes occurred due to the release of carbon from the ocean into the atmosphere that led to a temperature increase of 4–8 °C (7.2–14.4 °F) at the surface of the ocean. These hyperthermals led to increased perturbations in planktonic and benthic foraminifera, with a higher rate of sedimentation as a consequence of the warmer temperatures. Recent analysis of and research into these hyperthermals in the early Eocene has led to hypotheses that the hyperthermals are based on orbital parameters, in particular eccentricity and obliquity. The hyperthermals in the early Eocene, notably the Palaeocene–Eocene Thermal Maximum (PETM), the Eocene Thermal Maximum 2 (ETM2), and the Eocene Thermal Maximum 3 (ETM3), were analyzed and found that orbital control may have had a role in triggering the ETM2 and ETM3. Equable climate problem One of the unique features of the Eocene's climate as mentioned before was the equable and homogeneous climate that existed in the early parts of the Eocene. A multitude of proxies support the presence of a warmer equable climate being present during this period of time. A few of these proxies include the presence of fossils native to warm climates, such as crocodiles, located in the higher latitudes, the presence in the high latitudes of frost-intolerant flora such as palm trees which cannot survive during sustained freezes, and fossils of snakes found in the tropics that would require much higher average temperatures to sustain them. TEX86 BAYSPAR measurements indicate extremely high sea surface temperatures of 40 °C (104 °F) to 45 °C (113 °F) at low latitudes, although clumped isotope analyses point to a maximum low latitude sea surface temperature of 36.3 °C (97.3 °F) ± 1.9 °C (35.4 °F) during the Early Eocene Climatic Optimum. Relative to present-day values, bottom water temperatures are 10 °C (18 °F) higher according to isotope proxies. With these bottom water temperatures, temperatures in areas where deep water forms near the poles are unable to be much cooler than the bottom water temperatures.An issue arises, however, when trying to model the Eocene and reproduce the results that are found with the proxy data. Using all different ranges of greenhouse gasses that occurred during the early Eocene, models were unable to produce the warming that was found at the poles and the reduced seasonality that occurs with winters at the poles being substantially warmer. The models, while accurately predicting the tropics, tend to produce significantly cooler temperatures of up to 20 °C (36 °F) colder than the actual determined temperature at the poles. This error has been classified as the "equable climate problem". To solve this problem, the solution would involve finding a process to warm the poles without warming the tropics. Some hypotheses and tests which attempt to find the process are listed below. Large lakes Due to the nature of water as opposed to land, less temperature variability would be present if a large body of water is also present. In an attempt to try to mitigate the cooling polar temperatures, large lakes were proposed to mitigate seasonal climate changes. To replicate this case, a lake was inserted into North America and a climate model was run using varying carbon dioxide levels. The model runs concluded that while the lake did reduce the seasonality of the region greater than just an increase in carbon dioxide, the addition of a large lake was unable to reduce the seasonality to the levels shown by the floral and faunal data. Ocean heat transport The transport of heat from the tropics to the poles, much like how ocean heat transport functions in modern times, was considered a possibility for the increased temperature and reduced seasonality for the poles. With the increased sea surface temperatures and the increased temperature of the deep ocean water during the early Eocene, one common hypothesis was that due to these increases there would be a greater transport of heat from the tropics to the poles. Simulating these differences, the models produced lower heat transport due to the lower temperature gradients and were unsuccessful in producing an equable climate from only ocean heat transport. Orbital parameters While typically seen as a control on ice growth and seasonality, the orbital parameters were theorized as a possible control on continental temperatures and seasonality. Simulating the Eocene by using an ice free planet, eccentricity, obliquity, and precession were modified in different model runs to determine all the possible different scenarios that could occur and their effects on temperature. One particular case led to warmer winters and cooler summer by up to 30% in the North American continent, and it reduced the seasonal variation of temperature by up to 75%. While orbital parameters did not produce the warming at the poles, the parameters did show a great effect on seasonality and needed to be considered. Polar stratospheric clouds Another method considered for producing the warm polar temperatures were polar stratospheric clouds. Polar stratospheric clouds are clouds that occur in the lower stratosphere at very low temperatures. Polar stratospheric clouds have a great impact on radiative forcing. Due to their minimal albedo properties and their optical thickness, polar stratospheric clouds act similar to a greenhouse gas and traps outgoing longwave radiation. Different types of polar stratospheric clouds occur in the atmosphere: polar stratospheric clouds that are created due to interactions with nitric or sulfuric acid and water (Type I) or polar stratospheric clouds that are created with only water ice (Type II).Methane is an important factor in the creation of the primary Type II polar stratospheric clouds that were created in the early Eocene. Since water vapor is the only supporting substance used in Type II polar stratospheric clouds, the presence of water vapor in the lower stratosphere is necessary where in most situations the presence of water vapor in the lower stratosphere is rare. When methane is oxidized, a significant amount of water vapor is released. Another requirement for polar stratospheric clouds is cold temperatures to ensure condensation and cloud production. Polar stratospheric cloud production, since it requires the cold temperatures, is usually limited to nighttime and winter conditions. With this combination of wetter and colder conditions in the lower stratosphere, polar stratospheric clouds could have formed over wide areas in Polar Regions.To test the polar stratospheric clouds effects on the Eocene climate, models were run comparing the effects of polar stratospheric clouds at the poles to an increase in atmospheric carbon dioxide. The polar stratospheric clouds had a warming effect on the poles, increasing temperatures by up to 20 °C in the winter months. A multitude of feedbacks also occurred in the models due to the polar stratospheric clouds' presence. Any ice growth was slowed immensely and would lead to any present ice melting. Only the poles were affected with the change in temperature and the tropics were unaffected, which with an increase in atmospheric carbon dioxide would also cause the tropics to increase in temperature. Due to the warming of the troposphere from the increased greenhouse effect of the polar stratospheric clouds, the stratosphere would cool and would potentially increase the amount of polar stratospheric clouds. While the polar stratospheric clouds could explain the reduction of the equator to pole temperature gradient and the increased temperatures at the poles during the early Eocene, there are a few drawbacks to maintaining polar stratospheric clouds for an extended period of time. Separate model runs were used to determine the sustainability of the polar stratospheric clouds. It was determined that in order to maintain the lower stratospheric water vapor, methane would need to be continually released and sustained. In addition, the amounts of ice and condensation nuclei would need to be high in order for the polar stratospheric cloud to sustain itself and eventually expand. Middle Eocene The Eocene is not only known for containing the warmest period during the Cenozoic; it also marked the decline into an icehouse climate and the rapid expansion of the Antarctic ice sheet. The transition from a warming climate into a cooling climate began at around 49 Ma. Isotopes of carbon and oxygen indicate a shift to a global cooling climate. The cause of the cooling has been attributed to a significant decrease of >2,000 ppm in atmospheric carbon dioxide concentrations. One proposed cause of the reduction in carbon dioxide during the warming to cooling transition was the azolla event. With the equable climate during the early Eocene, warm temperatures in the arctic allowed for the growth of azolla, which is a floating aquatic fern, on the Arctic Ocean. The significantly high amounts of carbon dioxide also acted to facilitate azolla blooms across the Arctic Ocean. Compared to current carbon dioxide levels, these azolla grew rapidly in the enhanced carbon dioxide levels found in the early Eocene. The isolation of the Arctic Ocean, evidenced by euxinia that occurred at this time, led to stagnant waters and as the azolla sank to the sea floor, they became part of the sediments on the seabed and effectively sequestered the carbon by locking it out of the atmosphere for good. The ability for the azolla to sequester carbon is exceptional, and the enhanced burial of azolla could have had a significant effect on the world atmospheric carbon content and may have been the event to begin the transition into an ice house climate. The azolla event could have led to a draw down of atmospheric carbon dioxide of up to 470 ppm. Assuming the carbon dioxide concentrations were at 900 ppmv prior to the Azolla Event they would have dropped to 430 ppmv, or 30 ppmv more than they are today, after the Azolla Event. This cooling trend at the end of the Early Eocene Climatic Optimum has also been proposed to have been caused by increased siliceous plankton productivity and marine carbon burial, which also helped draw carbon dioxide out of the atmosphere. Cooling after this event continued due to continual decrease in atmospheric carbon dioxide from organic productivity and weathering from mountain building.Global cooling continued until there was a major reversal from cooling to warming in the Bartonian. This warming event, signifying a sudden and temporary reversal of the cooling conditions, is known as the Middle Eocene Climatic Optimum (MECO). At around 41.5 Ma, stable isotopic analysis of samples from Southern Ocean drilling sites indicated a warming event for 600,000 years. A similar shift in carbon isotopes is known from the Northern Hemisphere in the Scaglia Limestones of Italy. Oxygen isotope analysis showed a large negative change in the proportion of heavier oxygen isotopes to lighter oxygen isotopes, which indicates an increase in global temperatures. The warming is considered to be primarily due to carbon dioxide increases, because carbon isotope signatures rule out major methane release during this short-term warming. A sharp increase in atmospheric carbon dioxide was observed with a maximum of 4,000 ppm: the highest amount of atmospheric carbon dioxide detected during the Eocene. Other studies suggest a more modest rise in carbon dioxide levels. The increase in atmospheric carbon dioxide has also been hypothesised to have been driven by increased seafloor spreading rates and metamorphic decarbonation reactions between Australia and Antarctica and increased amounts of volcanism in the region. One possible cause of atmospheric carbon dioxide increase could have been a sudden increase due to metamorphic release due to continental drift and collision of India with Asia and the resulting formation of the Himalayas; however, data on the exact timing of metamorphic release of atmospheric carbon dioxide is not well resolved in the data. Recent studies have mentioned, however, that the removal of the ocean between Asia and India could have released significant amounts of carbon dioxide. Another hypothesis still implicates a diminished negative feedback of silicate weathering as a result of continental rocks having become less weatherable during the warm Early and Middle Eocene, allowing volcanically released carbon dioxide to persist in the atmosphere for longer. Yet another explanation hypothesises that MECO warming was caused by the simultaneous occurrence of minima in both the 400 kyr and 2.4 Myr eccentricity cycles. During the MECO, sea surface temperatures in the Tethys Ocean jumped to 32-36 °C, and Tethyan seawater became more dysoxic. A decline in carbonate accumulation at ocean depths of greater than three kilometres took place synchronously with the peak of the MECO, signifying ocean acidification took place in the deep ocean. An abrupt decrease in lakewater salinity in western North America occurred during this warming interval. This warming is short lived, as benthic oxygen isotope records indicate a return to cooling at ~40 Ma. Late Eocene At the end of the Middle Eocene Climatic Optimum, cooling and the carbon dioxide drawdown continued through the late Eocene and into the Eocene–Oligocene transition around 34 Ma. The post-MECO cooling brought with it a major aridification trend in Asia. The cooling during the initial stages of the opening of the Drake Passage ~38.5 Ma was not global, as evidenced by an absence of cooling in the North Atlantic. During the cooling period, benthic oxygen isotopes show the possibility of ice creation and ice increase during this later cooling. The end of the Eocene and beginning of the Oligocene is marked with the massive expansion of area of the Antarctic ice sheet that was a major step into the icehouse climate. Multiple proxies, such as oxygen isotopes and alkenones, indicate that at the Eocene–Oligocene transition, the atmospheric carbon dioxide concentration had decreased to around 750–800 ppm, approximately twice that of present levels. Along with the decrease of atmospheric carbon dioxide reducing the global temperature, orbital factors in ice creation can be seen with 100,000-year and 400,000-year fluctuations in benthic oxygen isotope records. Another major contribution to the expansion of the ice sheet was the creation of the Antarctic Circumpolar Current. The creation of the Antarctic circumpolar current would isolate the cold water around the Antarctic, which would reduce heat transport to the Antarctic along with creating ocean gyres that result in the upwelling of colder bottom waters. The issue with this hypothesis of the consideration of this being a factor for the Eocene-Oligocene transition is the timing of the creation of the circulation is uncertain. For Drake Passage, sediments indicate the opening occurred ~41 Ma while tectonics indicate that this occurred ~32 Ma. Flora During the early-middle Eocene, forests covered most of the Earth including the poles. Tropical forests extended across much of modern Africa, South America, Central America, India, South-east Asia and China. Paratropical forests grew over North America, Europe and Russia, with broad-leafed evergreen and broad-leafed deciduous forests at higher latitudes.Polar forests were quite extensive. Fossils and even preserved remains of trees such as swamp cypress and dawn redwood from the Eocene have been found on Ellesmere Island in the Arctic. Even at that time, Ellesmere Island was only a few degrees in latitude further south than it is today. Fossils of subtropical and even tropical trees and plants from the Eocene also have been found in Greenland and Alaska. Tropical rainforests grew as far north as northern North America and Europe.Palm trees were growing as far north as Alaska and northern Europe during the early Eocene, although they became less abundant as the climate cooled. Dawn redwoods were far more extensive as well.The earliest definitive Eucalyptus fossils were dated from 51.9 Mya, and were found in the Laguna del Hunco deposit in Chubut province in Argentina.Cooling began mid-period, and by the end of the Eocene continental interiors had begun to dry, with forests thinning considerably in some areas. The newly evolved grasses were still confined to river banks and lake shores, and had not yet expanded into plains and savannas.The cooling also brought seasonal changes. Deciduous trees, better able to cope with large temperature changes, began to overtake evergreen tropical species. By the end of the period, deciduous forests covered large parts of the northern continents, including North America, Eurasia and the Arctic, and rainforests held on only in equatorial South America, Africa, India and Australia.Antarctica began the Eocene fringed with a warm temperate to sub-tropical rainforest. Pollen found in Prydz Bay from the Eocene suggest taiga forest existed there. It became much colder as the period progressed; the heat-loving tropical flora was wiped out, and by the beginning of the Oligocene, the continent hosted deciduous forests and vast stretches of tundra. Fauna During the Eocene, plants and marine faunas became quite modern. Many modern bird orders first appeared in the Eocene. The Eocene oceans were warm and teeming with fish and other sea life. Mammals The oldest known fossils of most of the modern mammal orders appear within a brief period during the early Eocene. At the beginning of the Eocene, several new mammal groups arrived in North America. These modern mammals, like artiodactyls, perissodactyls, and primates, had features like long, thin legs, feet, and hands capable of grasping, as well as differentiated teeth adapted for chewing. Dwarf forms reigned. All the members of the new mammal orders were small, under 10 kg; based on comparisons of tooth size, Eocene mammals were only 60% of the size of the primitive Palaeocene mammals that preceded them. They were also smaller than the mammals that followed them. It is assumed that the hot Eocene temperatures favored smaller animals that were better able to manage the heat.Both groups of modern ungulates (hoofed animals) became prevalent because of a major radiation between Europe and North America, along with carnivorous ungulates like Mesonyx. Early forms of many other modern mammalian orders appeared, including horses (most notably the Eohippus), bats, proboscidians (elephants), primates, rodents, and marsupials. Older primitive forms of mammals declined in variety and importance. Important Eocene land fauna fossil remains have been found in western North America, Europe, Patagonia, Egypt, and southeast Asia. Marine fauna are best known from South Asia and the southeast United States.Established megafauna of the Eocene include the Uintatherium, Arsinoitherium, and brontotheres, in which the former two, unlike the latter, did not belong to ungulates but groups that became extinct shortly after their establishments. Large terrestrial mammalian predators began to take form as the terrestrial carnivores like the Hyaenodon and Daphoenus (the earliest lineage of a once-successful predatory family known as bear dogs). Entelodonts meanwhile established themselves as some of the largest omnivores. The first nimravids, including Dinictis, established themselves as amongst the first feliforms to appear. Their groups became highly successful and continued to live past the Eocene. Basilosaurus is a very well-known Eocene whale, but whales as a group had become very diverse during the Eocene, which is when the major transitions from being terrestrial to fully aquatic in cetaceans occurred. The first sirenians were evolving at this time, and would eventually evolve into the extant manatees and dugongs. It is thought that millions of years after the Cretaceous-Paleogene extinction event, brain sizes of mammals now started to increase, "likely driven by a need for greater cognition in increasingly complex environments". Birds Eocene birds include some enigmatic groups with resemblances to modern forms, some of which continued from the Paleocene. Bird taxa of the Eocene include carnivorous psittaciforms, such as Messelasturidae, Halcyornithidae, large flightless forms such as Gastornis and Eleutherornis, long legged falcon Masillaraptor, ancient galliforms such as Gallinuloides, putative rail relatives of the family Songziidae, various pseudotooth birds such as Gigantornis, the ibis relative Rhynchaeites, primitive swifts of the genus Aegialornis, and primitive penguins such as Archaeospheniscus and Inkayacu. Reptiles Reptile fossils from this time, such as fossils of pythons and turtles, are abundant. Insects and arachnids Several rich fossil insect faunas are known from the Eocene, notably the Baltic amber found mainly along the south coast of the Baltic Sea, amber from the Paris Basin, France, the Fur Formation, Denmark, and the Bembridge Marls from the Isle of Wight, England. Insects found in Eocene deposits mostly belong to genera that exist today, though their range has often shifted since the Eocene. For instance the bibionid genus Plecia is common in fossil faunas from presently temperate areas, but only lives in the tropics and subtropics today. Gallery See also Bolca in Italy List of fossil sites (with link directory) London Clay Messel pit in Germany Wadi El Hitan in Egypt Notes References Further reading Ogg, Jim; June, 2004, Overview of Global Boundary Stratotype Sections and Points (GSSP's) Global Stratotype Sections and Points Accessed April 30, 2006. Stanley, Steven M. Earth System History. New York: W.H. Freeman and Company, 1999. ISBN 0-7167-2882-6 External links PaleoMap Project Paleos Eocene page PBS Deep Time: Eocene Eocene and Oligocene Fossils The UPenn Fossil Forest Project, focusing on the Eocene polar forests in Ellesmere Island, Canada Basilosaurus Primitive Eocene Whales Basilosaurus - The plesiosaur that wasn't.... Detailed maps of Tertiary Western North America Map of Eocene Earth Eocene Microfossils: 60+ images of Foraminifera Eocene Epoch. (2011). In Encyclopædia Britannica. Retrieved from Eocene Epoch \| geochronology	instance of	{ "answer_start": [ 9824 ], "text": [ "series" ] }
The Eocene (IPA: EE-ə-seen, EE-oh-) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name Eocene comes from the Ancient Greek ἠώς (ēṓs, "dawn") and καινός (kainós, "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the Grande Coupure (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the epoch are well identified, though their exact dates are slightly uncertain. Etymology The term "Eocene" is derived from Ancient Greek ἠώς eos meaning "dawn", and καινός kainos meaning "new" or "recent", as the epoch saw the dawn of recent, or modern, life. Scottish geologist Charles Lyell (ignoring the Quaternary) had divided the Tertiary Epoch into the Eocene, Miocene, Pliocene, and New Pliocene (Holocene) Periods in 1833. British geologist John Phillips had proposed the Cenozoic in 1840 in place of the Tertiary, and Austrian paleontologist Moritz Hörnes had introduced the Paleogene for the Eocene and Neogene for the Miocene and Pliocene in 1853. After decades of inconsistent usage, the newly formed International Commission on Stratigraphy (ICS), in 1969, standardized stratigraphy based on the prevailing opinions in Europe: the Cenozoic Era subdivided into the Tertiary and Quaternary sub-eras, and the Tertiary subdivided into the Paleogene and Neogene periods. In 1978, the Paleogene was officially defined as the Paleocene, Eocene, and Oligocene epochs; and the Neogene as the Miocene and Pliocene epochs. In 1989, Tertiary and Quaternary were removed from the time scale due to the arbitrary nature of their boundary, but Quaternary was reinstated in 2009. Geology Boundaries The beginning of the Eocene is marked by the Paleocene–Eocene Thermal Maximum, a short period of intense warming and ocean acidification brought about by the release of carbon en masse into the atmosphere and ocean systems, which led to a mass extinction of 30–50% of benthic foraminifera–single-celled species which are used as bioindicators of the health of a marine ecosystem—one of the largest in the Cenozoic. This event happened around 55.8 mya, and was one of the most significant periods of global change during the Cenozoic.The end of the Eocene was marked by the Eocene–Oligocene extinction event, also known as the Grande Coupure. Stratigraphy The Eocene is conventionally divided into early (56–47.8 Ma), middle (47.8–38 Ma), and late (38–33.9 Ma) subdivisions. The corresponding rocks are referred to as lower, middle, and upper Eocene. The Ypresian Stage constitutes the lower, the Priabonian Stage the upper; and the Lutetian and Bartonian stages are united as the middle Eocene. Palaeogeography and tectonics During the Eocene, the continents continued to drift toward their present positions. At the beginning of the period, Australia and Antarctica remained connected, and warm equatorial currents may have mixed with colder Antarctic waters, distributing the heat around the planet and keeping global temperatures high. When Australia split from the southern continent around 45 Ma, the warm equatorial currents were routed away from Antarctica. An isolated cold water channel developed between the two continents. However, modeling results call into question the thermal isolation model for late Eocene cooling, and decreasing carbon dioxide levels in the atmosphere may have been more important. Once the Antarctic region began to cool down, the ocean surrounding Antarctica began to freeze, sending cold water and icefloes north and reinforcing the cooling.The northern supercontinent of Laurasia began to fragment, as Europe, Greenland and North America drifted apart.In western North America, the Laramide Orogeny came to an end in the Eocene, and compression was replaced with crustal extension that ultimately gave rise to the Basin and Range Province. Huge lakes formed in the high flat basins among uplifts, resulting in the deposition of the Green River Formation lagerstätte.At about 35 Ma, an asteroid impact on the eastern coast of North America formed the Chesapeake Bay impact crater.In Europe, the Tethys Sea finally disappeared, while the uplift of the Alps isolated its final remnant, the Mediterranean, and created another shallow sea with island archipelagos to the north. Though the North Atlantic was opening, a land connection appears to have remained between North America and Europe since the faunas of the two regions are very similar.Eurasia was separated in three different landmasses 50 Ma; Western Europe, Balkanatolia and Asia. About 40 Ma, Balkanatolia and Asia were connected, while Europe was connected 34 Ma.India collided with Asia, folding to initiate formation of the Himalayas. India collided with the Kohistan–Ladakh Arc around 50.2 Ma and with Karakoram around 40.4 Ma, with the final collision between Asia and India occurring ~40 Ma. Climate The Eocene Epoch contained a wide variety of different climate conditions that includes the warmest climate in the Cenozoic Era, and arguably the warmest time interval since the Permian-Triassic mass extinction and Early Triassic, and ends in an icehouse climate. The evolution of the Eocene climate began with warming after the end of the Paleocene–Eocene Thermal Maximum (PETM) at 56 Ma to a maximum during the Eocene Optimum at around 49 Ma. Recent study show elevation-dependent temperature changes during the Eocene hothouse. During this period of time, little to no ice was present on Earth with a smaller difference in temperature from the equator to the poles. Because of this the maximum sea level was 150 meters higher than current levels. Following the maximum was a descent into an icehouse climate from the Eocene Optimum to the Eocene-Oligocene transition at 34 Ma. During this decrease, ice began to reappear at the poles, and the Eocene-Oligocene transition is the period of time where the Antarctic ice sheet began to rapidly expand. Early Eocene Greenhouse gases, in particular carbon dioxide and methane, played a significant role during the Eocene in controlling the surface temperature. The end of the PETM was met with very large sequestration of carbon dioxide into the forms of methane clathrate, coal, and crude oil at the bottom of the Arctic Ocean, that reduced the atmospheric carbon dioxide. This event was similar in magnitude to the massive release of greenhouse gasses at the beginning of the PETM, and it is hypothesized that the sequestration was mainly due to organic carbon burial and weathering of silicates. For the early Eocene there is much discussion on how much carbon dioxide was in the atmosphere. This is due to numerous proxies representing different atmospheric carbon dioxide content. For example, diverse geochemical and paleontological proxies indicate that at the maximum of global warmth the atmospheric carbon dioxide values were at 700–900 ppm while other proxies such as pedogenic (soil building) carbonate and marine boron isotopes indicate large changes of carbon dioxide of over 2,000 ppm over periods of time of less than 1 million years. Sources for this large influx of carbon dioxide could be attributed to volcanic out-gassing due to North Atlantic rifting or oxidation of methane stored in large reservoirs deposited from the PETM event in the sea floor or wetland environments. For contrast, today the carbon dioxide levels are at 400 ppm or 0.04%. At about the beginning of the Eocene Epoch (55.8–33.9 Ma) the amount of oxygen in the earth's atmosphere more or less doubled.During the early Eocene, methane was another greenhouse gas that had a drastic effect on the climate. The warming effect of one ton of methane dimensions unspecified is approximately 30 times the warming effect of one ton of carbon on a 100-year scale (i.e., methane has a global warming potential of 29.8±11). Most of the methane released to the atmosphere during this period of time would have been from wetlands, swamps, and forests. The atmospheric methane concentration today is 0.000179% or 1.79 ppmv. As a result of the warmer climate and the sea level rise associated with the early Eocene, more wetlands, more forests, and more coal deposits would have been available for methane release. If we compare the early Eocene production of methane to current levels of atmospheric methane, the early Eocene would have produced triple the amount of methane. The warm temperatures during the early Eocene could have increased methane production rates, and methane that is released into the atmosphere would in turn warm the troposphere, cool the stratosphere, and produce water vapor and carbon dioxide through oxidation. Biogenic production of methane produces carbon dioxide and water vapor along with the methane, as well as yielding infrared radiation. The breakdown of methane in an atmosphere containing oxygen produces carbon monoxide, water vapor and infrared radiation. The carbon monoxide is not stable, so it eventually becomes carbon dioxide and in doing so releases yet more infrared radiation. Water vapor traps more infrared than does carbon dioxide. Hyperthermals through the early Eocene During the warming in the early Eocene between 55 and 52 Ma, there were a series of short-term changes of carbon isotope composition in the ocean. These isotope changes occurred due to the release of carbon from the ocean into the atmosphere that led to a temperature increase of 4–8 °C (7.2–14.4 °F) at the surface of the ocean. These hyperthermals led to increased perturbations in planktonic and benthic foraminifera, with a higher rate of sedimentation as a consequence of the warmer temperatures. Recent analysis of and research into these hyperthermals in the early Eocene has led to hypotheses that the hyperthermals are based on orbital parameters, in particular eccentricity and obliquity. The hyperthermals in the early Eocene, notably the Palaeocene–Eocene Thermal Maximum (PETM), the Eocene Thermal Maximum 2 (ETM2), and the Eocene Thermal Maximum 3 (ETM3), were analyzed and found that orbital control may have had a role in triggering the ETM2 and ETM3. Equable climate problem One of the unique features of the Eocene's climate as mentioned before was the equable and homogeneous climate that existed in the early parts of the Eocene. A multitude of proxies support the presence of a warmer equable climate being present during this period of time. A few of these proxies include the presence of fossils native to warm climates, such as crocodiles, located in the higher latitudes, the presence in the high latitudes of frost-intolerant flora such as palm trees which cannot survive during sustained freezes, and fossils of snakes found in the tropics that would require much higher average temperatures to sustain them. TEX86 BAYSPAR measurements indicate extremely high sea surface temperatures of 40 °C (104 °F) to 45 °C (113 °F) at low latitudes, although clumped isotope analyses point to a maximum low latitude sea surface temperature of 36.3 °C (97.3 °F) ± 1.9 °C (35.4 °F) during the Early Eocene Climatic Optimum. Relative to present-day values, bottom water temperatures are 10 °C (18 °F) higher according to isotope proxies. With these bottom water temperatures, temperatures in areas where deep water forms near the poles are unable to be much cooler than the bottom water temperatures.An issue arises, however, when trying to model the Eocene and reproduce the results that are found with the proxy data. Using all different ranges of greenhouse gasses that occurred during the early Eocene, models were unable to produce the warming that was found at the poles and the reduced seasonality that occurs with winters at the poles being substantially warmer. The models, while accurately predicting the tropics, tend to produce significantly cooler temperatures of up to 20 °C (36 °F) colder than the actual determined temperature at the poles. This error has been classified as the "equable climate problem". To solve this problem, the solution would involve finding a process to warm the poles without warming the tropics. Some hypotheses and tests which attempt to find the process are listed below. Large lakes Due to the nature of water as opposed to land, less temperature variability would be present if a large body of water is also present. In an attempt to try to mitigate the cooling polar temperatures, large lakes were proposed to mitigate seasonal climate changes. To replicate this case, a lake was inserted into North America and a climate model was run using varying carbon dioxide levels. The model runs concluded that while the lake did reduce the seasonality of the region greater than just an increase in carbon dioxide, the addition of a large lake was unable to reduce the seasonality to the levels shown by the floral and faunal data. Ocean heat transport The transport of heat from the tropics to the poles, much like how ocean heat transport functions in modern times, was considered a possibility for the increased temperature and reduced seasonality for the poles. With the increased sea surface temperatures and the increased temperature of the deep ocean water during the early Eocene, one common hypothesis was that due to these increases there would be a greater transport of heat from the tropics to the poles. Simulating these differences, the models produced lower heat transport due to the lower temperature gradients and were unsuccessful in producing an equable climate from only ocean heat transport. Orbital parameters While typically seen as a control on ice growth and seasonality, the orbital parameters were theorized as a possible control on continental temperatures and seasonality. Simulating the Eocene by using an ice free planet, eccentricity, obliquity, and precession were modified in different model runs to determine all the possible different scenarios that could occur and their effects on temperature. One particular case led to warmer winters and cooler summer by up to 30% in the North American continent, and it reduced the seasonal variation of temperature by up to 75%. While orbital parameters did not produce the warming at the poles, the parameters did show a great effect on seasonality and needed to be considered. Polar stratospheric clouds Another method considered for producing the warm polar temperatures were polar stratospheric clouds. Polar stratospheric clouds are clouds that occur in the lower stratosphere at very low temperatures. Polar stratospheric clouds have a great impact on radiative forcing. Due to their minimal albedo properties and their optical thickness, polar stratospheric clouds act similar to a greenhouse gas and traps outgoing longwave radiation. Different types of polar stratospheric clouds occur in the atmosphere: polar stratospheric clouds that are created due to interactions with nitric or sulfuric acid and water (Type I) or polar stratospheric clouds that are created with only water ice (Type II).Methane is an important factor in the creation of the primary Type II polar stratospheric clouds that were created in the early Eocene. Since water vapor is the only supporting substance used in Type II polar stratospheric clouds, the presence of water vapor in the lower stratosphere is necessary where in most situations the presence of water vapor in the lower stratosphere is rare. When methane is oxidized, a significant amount of water vapor is released. Another requirement for polar stratospheric clouds is cold temperatures to ensure condensation and cloud production. Polar stratospheric cloud production, since it requires the cold temperatures, is usually limited to nighttime and winter conditions. With this combination of wetter and colder conditions in the lower stratosphere, polar stratospheric clouds could have formed over wide areas in Polar Regions.To test the polar stratospheric clouds effects on the Eocene climate, models were run comparing the effects of polar stratospheric clouds at the poles to an increase in atmospheric carbon dioxide. The polar stratospheric clouds had a warming effect on the poles, increasing temperatures by up to 20 °C in the winter months. A multitude of feedbacks also occurred in the models due to the polar stratospheric clouds' presence. Any ice growth was slowed immensely and would lead to any present ice melting. Only the poles were affected with the change in temperature and the tropics were unaffected, which with an increase in atmospheric carbon dioxide would also cause the tropics to increase in temperature. Due to the warming of the troposphere from the increased greenhouse effect of the polar stratospheric clouds, the stratosphere would cool and would potentially increase the amount of polar stratospheric clouds. While the polar stratospheric clouds could explain the reduction of the equator to pole temperature gradient and the increased temperatures at the poles during the early Eocene, there are a few drawbacks to maintaining polar stratospheric clouds for an extended period of time. Separate model runs were used to determine the sustainability of the polar stratospheric clouds. It was determined that in order to maintain the lower stratospheric water vapor, methane would need to be continually released and sustained. In addition, the amounts of ice and condensation nuclei would need to be high in order for the polar stratospheric cloud to sustain itself and eventually expand. Middle Eocene The Eocene is not only known for containing the warmest period during the Cenozoic; it also marked the decline into an icehouse climate and the rapid expansion of the Antarctic ice sheet. The transition from a warming climate into a cooling climate began at around 49 Ma. Isotopes of carbon and oxygen indicate a shift to a global cooling climate. The cause of the cooling has been attributed to a significant decrease of >2,000 ppm in atmospheric carbon dioxide concentrations. One proposed cause of the reduction in carbon dioxide during the warming to cooling transition was the azolla event. With the equable climate during the early Eocene, warm temperatures in the arctic allowed for the growth of azolla, which is a floating aquatic fern, on the Arctic Ocean. The significantly high amounts of carbon dioxide also acted to facilitate azolla blooms across the Arctic Ocean. Compared to current carbon dioxide levels, these azolla grew rapidly in the enhanced carbon dioxide levels found in the early Eocene. The isolation of the Arctic Ocean, evidenced by euxinia that occurred at this time, led to stagnant waters and as the azolla sank to the sea floor, they became part of the sediments on the seabed and effectively sequestered the carbon by locking it out of the atmosphere for good. The ability for the azolla to sequester carbon is exceptional, and the enhanced burial of azolla could have had a significant effect on the world atmospheric carbon content and may have been the event to begin the transition into an ice house climate. The azolla event could have led to a draw down of atmospheric carbon dioxide of up to 470 ppm. Assuming the carbon dioxide concentrations were at 900 ppmv prior to the Azolla Event they would have dropped to 430 ppmv, or 30 ppmv more than they are today, after the Azolla Event. This cooling trend at the end of the Early Eocene Climatic Optimum has also been proposed to have been caused by increased siliceous plankton productivity and marine carbon burial, which also helped draw carbon dioxide out of the atmosphere. Cooling after this event continued due to continual decrease in atmospheric carbon dioxide from organic productivity and weathering from mountain building.Global cooling continued until there was a major reversal from cooling to warming in the Bartonian. This warming event, signifying a sudden and temporary reversal of the cooling conditions, is known as the Middle Eocene Climatic Optimum (MECO). At around 41.5 Ma, stable isotopic analysis of samples from Southern Ocean drilling sites indicated a warming event for 600,000 years. A similar shift in carbon isotopes is known from the Northern Hemisphere in the Scaglia Limestones of Italy. Oxygen isotope analysis showed a large negative change in the proportion of heavier oxygen isotopes to lighter oxygen isotopes, which indicates an increase in global temperatures. The warming is considered to be primarily due to carbon dioxide increases, because carbon isotope signatures rule out major methane release during this short-term warming. A sharp increase in atmospheric carbon dioxide was observed with a maximum of 4,000 ppm: the highest amount of atmospheric carbon dioxide detected during the Eocene. Other studies suggest a more modest rise in carbon dioxide levels. The increase in atmospheric carbon dioxide has also been hypothesised to have been driven by increased seafloor spreading rates and metamorphic decarbonation reactions between Australia and Antarctica and increased amounts of volcanism in the region. One possible cause of atmospheric carbon dioxide increase could have been a sudden increase due to metamorphic release due to continental drift and collision of India with Asia and the resulting formation of the Himalayas; however, data on the exact timing of metamorphic release of atmospheric carbon dioxide is not well resolved in the data. Recent studies have mentioned, however, that the removal of the ocean between Asia and India could have released significant amounts of carbon dioxide. Another hypothesis still implicates a diminished negative feedback of silicate weathering as a result of continental rocks having become less weatherable during the warm Early and Middle Eocene, allowing volcanically released carbon dioxide to persist in the atmosphere for longer. Yet another explanation hypothesises that MECO warming was caused by the simultaneous occurrence of minima in both the 400 kyr and 2.4 Myr eccentricity cycles. During the MECO, sea surface temperatures in the Tethys Ocean jumped to 32-36 °C, and Tethyan seawater became more dysoxic. A decline in carbonate accumulation at ocean depths of greater than three kilometres took place synchronously with the peak of the MECO, signifying ocean acidification took place in the deep ocean. An abrupt decrease in lakewater salinity in western North America occurred during this warming interval. This warming is short lived, as benthic oxygen isotope records indicate a return to cooling at ~40 Ma. Late Eocene At the end of the Middle Eocene Climatic Optimum, cooling and the carbon dioxide drawdown continued through the late Eocene and into the Eocene–Oligocene transition around 34 Ma. The post-MECO cooling brought with it a major aridification trend in Asia. The cooling during the initial stages of the opening of the Drake Passage ~38.5 Ma was not global, as evidenced by an absence of cooling in the North Atlantic. During the cooling period, benthic oxygen isotopes show the possibility of ice creation and ice increase during this later cooling. The end of the Eocene and beginning of the Oligocene is marked with the massive expansion of area of the Antarctic ice sheet that was a major step into the icehouse climate. Multiple proxies, such as oxygen isotopes and alkenones, indicate that at the Eocene–Oligocene transition, the atmospheric carbon dioxide concentration had decreased to around 750–800 ppm, approximately twice that of present levels. Along with the decrease of atmospheric carbon dioxide reducing the global temperature, orbital factors in ice creation can be seen with 100,000-year and 400,000-year fluctuations in benthic oxygen isotope records. Another major contribution to the expansion of the ice sheet was the creation of the Antarctic Circumpolar Current. The creation of the Antarctic circumpolar current would isolate the cold water around the Antarctic, which would reduce heat transport to the Antarctic along with creating ocean gyres that result in the upwelling of colder bottom waters. The issue with this hypothesis of the consideration of this being a factor for the Eocene-Oligocene transition is the timing of the creation of the circulation is uncertain. For Drake Passage, sediments indicate the opening occurred ~41 Ma while tectonics indicate that this occurred ~32 Ma. Flora During the early-middle Eocene, forests covered most of the Earth including the poles. Tropical forests extended across much of modern Africa, South America, Central America, India, South-east Asia and China. Paratropical forests grew over North America, Europe and Russia, with broad-leafed evergreen and broad-leafed deciduous forests at higher latitudes.Polar forests were quite extensive. Fossils and even preserved remains of trees such as swamp cypress and dawn redwood from the Eocene have been found on Ellesmere Island in the Arctic. Even at that time, Ellesmere Island was only a few degrees in latitude further south than it is today. Fossils of subtropical and even tropical trees and plants from the Eocene also have been found in Greenland and Alaska. Tropical rainforests grew as far north as northern North America and Europe.Palm trees were growing as far north as Alaska and northern Europe during the early Eocene, although they became less abundant as the climate cooled. Dawn redwoods were far more extensive as well.The earliest definitive Eucalyptus fossils were dated from 51.9 Mya, and were found in the Laguna del Hunco deposit in Chubut province in Argentina.Cooling began mid-period, and by the end of the Eocene continental interiors had begun to dry, with forests thinning considerably in some areas. The newly evolved grasses were still confined to river banks and lake shores, and had not yet expanded into plains and savannas.The cooling also brought seasonal changes. Deciduous trees, better able to cope with large temperature changes, began to overtake evergreen tropical species. By the end of the period, deciduous forests covered large parts of the northern continents, including North America, Eurasia and the Arctic, and rainforests held on only in equatorial South America, Africa, India and Australia.Antarctica began the Eocene fringed with a warm temperate to sub-tropical rainforest. Pollen found in Prydz Bay from the Eocene suggest taiga forest existed there. It became much colder as the period progressed; the heat-loving tropical flora was wiped out, and by the beginning of the Oligocene, the continent hosted deciduous forests and vast stretches of tundra. Fauna During the Eocene, plants and marine faunas became quite modern. Many modern bird orders first appeared in the Eocene. The Eocene oceans were warm and teeming with fish and other sea life. Mammals The oldest known fossils of most of the modern mammal orders appear within a brief period during the early Eocene. At the beginning of the Eocene, several new mammal groups arrived in North America. These modern mammals, like artiodactyls, perissodactyls, and primates, had features like long, thin legs, feet, and hands capable of grasping, as well as differentiated teeth adapted for chewing. Dwarf forms reigned. All the members of the new mammal orders were small, under 10 kg; based on comparisons of tooth size, Eocene mammals were only 60% of the size of the primitive Palaeocene mammals that preceded them. They were also smaller than the mammals that followed them. It is assumed that the hot Eocene temperatures favored smaller animals that were better able to manage the heat.Both groups of modern ungulates (hoofed animals) became prevalent because of a major radiation between Europe and North America, along with carnivorous ungulates like Mesonyx. Early forms of many other modern mammalian orders appeared, including horses (most notably the Eohippus), bats, proboscidians (elephants), primates, rodents, and marsupials. Older primitive forms of mammals declined in variety and importance. Important Eocene land fauna fossil remains have been found in western North America, Europe, Patagonia, Egypt, and southeast Asia. Marine fauna are best known from South Asia and the southeast United States.Established megafauna of the Eocene include the Uintatherium, Arsinoitherium, and brontotheres, in which the former two, unlike the latter, did not belong to ungulates but groups that became extinct shortly after their establishments. Large terrestrial mammalian predators began to take form as the terrestrial carnivores like the Hyaenodon and Daphoenus (the earliest lineage of a once-successful predatory family known as bear dogs). Entelodonts meanwhile established themselves as some of the largest omnivores. The first nimravids, including Dinictis, established themselves as amongst the first feliforms to appear. Their groups became highly successful and continued to live past the Eocene. Basilosaurus is a very well-known Eocene whale, but whales as a group had become very diverse during the Eocene, which is when the major transitions from being terrestrial to fully aquatic in cetaceans occurred. The first sirenians were evolving at this time, and would eventually evolve into the extant manatees and dugongs. It is thought that millions of years after the Cretaceous-Paleogene extinction event, brain sizes of mammals now started to increase, "likely driven by a need for greater cognition in increasingly complex environments". Birds Eocene birds include some enigmatic groups with resemblances to modern forms, some of which continued from the Paleocene. Bird taxa of the Eocene include carnivorous psittaciforms, such as Messelasturidae, Halcyornithidae, large flightless forms such as Gastornis and Eleutherornis, long legged falcon Masillaraptor, ancient galliforms such as Gallinuloides, putative rail relatives of the family Songziidae, various pseudotooth birds such as Gigantornis, the ibis relative Rhynchaeites, primitive swifts of the genus Aegialornis, and primitive penguins such as Archaeospheniscus and Inkayacu. Reptiles Reptile fossils from this time, such as fossils of pythons and turtles, are abundant. Insects and arachnids Several rich fossil insect faunas are known from the Eocene, notably the Baltic amber found mainly along the south coast of the Baltic Sea, amber from the Paris Basin, France, the Fur Formation, Denmark, and the Bembridge Marls from the Isle of Wight, England. Insects found in Eocene deposits mostly belong to genera that exist today, though their range has often shifted since the Eocene. For instance the bibionid genus Plecia is common in fossil faunas from presently temperate areas, but only lives in the tropics and subtropics today. Gallery See also Bolca in Italy List of fossil sites (with link directory) London Clay Messel pit in Germany Wadi El Hitan in Egypt Notes References Further reading Ogg, Jim; June, 2004, Overview of Global Boundary Stratotype Sections and Points (GSSP's) Global Stratotype Sections and Points Accessed April 30, 2006. Stanley, Steven M. Earth System History. New York: W.H. Freeman and Company, 1999. ISBN 0-7167-2882-6 External links PaleoMap Project Paleos Eocene page PBS Deep Time: Eocene Eocene and Oligocene Fossils The UPenn Fossil Forest Project, focusing on the Eocene polar forests in Ellesmere Island, Canada Basilosaurus Primitive Eocene Whales Basilosaurus - The plesiosaur that wasn't.... Detailed maps of Tertiary Western North America Map of Eocene Earth Eocene Microfossils: 60+ images of Foraminifera Eocene Epoch. (2011). In Encyclopædia Britannica. Retrieved from Eocene Epoch \| geochronology	named after	{ "answer_start": [ 254 ], "text": [ "dawn" ] }
The Eocene (IPA: EE-ə-seen, EE-oh-) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name Eocene comes from the Ancient Greek ἠώς (ēṓs, "dawn") and καινός (kainós, "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the Grande Coupure (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the epoch are well identified, though their exact dates are slightly uncertain. Etymology The term "Eocene" is derived from Ancient Greek ἠώς eos meaning "dawn", and καινός kainos meaning "new" or "recent", as the epoch saw the dawn of recent, or modern, life. Scottish geologist Charles Lyell (ignoring the Quaternary) had divided the Tertiary Epoch into the Eocene, Miocene, Pliocene, and New Pliocene (Holocene) Periods in 1833. British geologist John Phillips had proposed the Cenozoic in 1840 in place of the Tertiary, and Austrian paleontologist Moritz Hörnes had introduced the Paleogene for the Eocene and Neogene for the Miocene and Pliocene in 1853. After decades of inconsistent usage, the newly formed International Commission on Stratigraphy (ICS), in 1969, standardized stratigraphy based on the prevailing opinions in Europe: the Cenozoic Era subdivided into the Tertiary and Quaternary sub-eras, and the Tertiary subdivided into the Paleogene and Neogene periods. In 1978, the Paleogene was officially defined as the Paleocene, Eocene, and Oligocene epochs; and the Neogene as the Miocene and Pliocene epochs. In 1989, Tertiary and Quaternary were removed from the time scale due to the arbitrary nature of their boundary, but Quaternary was reinstated in 2009. Geology Boundaries The beginning of the Eocene is marked by the Paleocene–Eocene Thermal Maximum, a short period of intense warming and ocean acidification brought about by the release of carbon en masse into the atmosphere and ocean systems, which led to a mass extinction of 30–50% of benthic foraminifera–single-celled species which are used as bioindicators of the health of a marine ecosystem—one of the largest in the Cenozoic. This event happened around 55.8 mya, and was one of the most significant periods of global change during the Cenozoic.The end of the Eocene was marked by the Eocene–Oligocene extinction event, also known as the Grande Coupure. Stratigraphy The Eocene is conventionally divided into early (56–47.8 Ma), middle (47.8–38 Ma), and late (38–33.9 Ma) subdivisions. The corresponding rocks are referred to as lower, middle, and upper Eocene. The Ypresian Stage constitutes the lower, the Priabonian Stage the upper; and the Lutetian and Bartonian stages are united as the middle Eocene. Palaeogeography and tectonics During the Eocene, the continents continued to drift toward their present positions. At the beginning of the period, Australia and Antarctica remained connected, and warm equatorial currents may have mixed with colder Antarctic waters, distributing the heat around the planet and keeping global temperatures high. When Australia split from the southern continent around 45 Ma, the warm equatorial currents were routed away from Antarctica. An isolated cold water channel developed between the two continents. However, modeling results call into question the thermal isolation model for late Eocene cooling, and decreasing carbon dioxide levels in the atmosphere may have been more important. Once the Antarctic region began to cool down, the ocean surrounding Antarctica began to freeze, sending cold water and icefloes north and reinforcing the cooling.The northern supercontinent of Laurasia began to fragment, as Europe, Greenland and North America drifted apart.In western North America, the Laramide Orogeny came to an end in the Eocene, and compression was replaced with crustal extension that ultimately gave rise to the Basin and Range Province. Huge lakes formed in the high flat basins among uplifts, resulting in the deposition of the Green River Formation lagerstätte.At about 35 Ma, an asteroid impact on the eastern coast of North America formed the Chesapeake Bay impact crater.In Europe, the Tethys Sea finally disappeared, while the uplift of the Alps isolated its final remnant, the Mediterranean, and created another shallow sea with island archipelagos to the north. Though the North Atlantic was opening, a land connection appears to have remained between North America and Europe since the faunas of the two regions are very similar.Eurasia was separated in three different landmasses 50 Ma; Western Europe, Balkanatolia and Asia. About 40 Ma, Balkanatolia and Asia were connected, while Europe was connected 34 Ma.India collided with Asia, folding to initiate formation of the Himalayas. India collided with the Kohistan–Ladakh Arc around 50.2 Ma and with Karakoram around 40.4 Ma, with the final collision between Asia and India occurring ~40 Ma. Climate The Eocene Epoch contained a wide variety of different climate conditions that includes the warmest climate in the Cenozoic Era, and arguably the warmest time interval since the Permian-Triassic mass extinction and Early Triassic, and ends in an icehouse climate. The evolution of the Eocene climate began with warming after the end of the Paleocene–Eocene Thermal Maximum (PETM) at 56 Ma to a maximum during the Eocene Optimum at around 49 Ma. Recent study show elevation-dependent temperature changes during the Eocene hothouse. During this period of time, little to no ice was present on Earth with a smaller difference in temperature from the equator to the poles. Because of this the maximum sea level was 150 meters higher than current levels. Following the maximum was a descent into an icehouse climate from the Eocene Optimum to the Eocene-Oligocene transition at 34 Ma. During this decrease, ice began to reappear at the poles, and the Eocene-Oligocene transition is the period of time where the Antarctic ice sheet began to rapidly expand. Early Eocene Greenhouse gases, in particular carbon dioxide and methane, played a significant role during the Eocene in controlling the surface temperature. The end of the PETM was met with very large sequestration of carbon dioxide into the forms of methane clathrate, coal, and crude oil at the bottom of the Arctic Ocean, that reduced the atmospheric carbon dioxide. This event was similar in magnitude to the massive release of greenhouse gasses at the beginning of the PETM, and it is hypothesized that the sequestration was mainly due to organic carbon burial and weathering of silicates. For the early Eocene there is much discussion on how much carbon dioxide was in the atmosphere. This is due to numerous proxies representing different atmospheric carbon dioxide content. For example, diverse geochemical and paleontological proxies indicate that at the maximum of global warmth the atmospheric carbon dioxide values were at 700–900 ppm while other proxies such as pedogenic (soil building) carbonate and marine boron isotopes indicate large changes of carbon dioxide of over 2,000 ppm over periods of time of less than 1 million years. Sources for this large influx of carbon dioxide could be attributed to volcanic out-gassing due to North Atlantic rifting or oxidation of methane stored in large reservoirs deposited from the PETM event in the sea floor or wetland environments. For contrast, today the carbon dioxide levels are at 400 ppm or 0.04%. At about the beginning of the Eocene Epoch (55.8–33.9 Ma) the amount of oxygen in the earth's atmosphere more or less doubled.During the early Eocene, methane was another greenhouse gas that had a drastic effect on the climate. The warming effect of one ton of methane dimensions unspecified is approximately 30 times the warming effect of one ton of carbon on a 100-year scale (i.e., methane has a global warming potential of 29.8±11). Most of the methane released to the atmosphere during this period of time would have been from wetlands, swamps, and forests. The atmospheric methane concentration today is 0.000179% or 1.79 ppmv. As a result of the warmer climate and the sea level rise associated with the early Eocene, more wetlands, more forests, and more coal deposits would have been available for methane release. If we compare the early Eocene production of methane to current levels of atmospheric methane, the early Eocene would have produced triple the amount of methane. The warm temperatures during the early Eocene could have increased methane production rates, and methane that is released into the atmosphere would in turn warm the troposphere, cool the stratosphere, and produce water vapor and carbon dioxide through oxidation. Biogenic production of methane produces carbon dioxide and water vapor along with the methane, as well as yielding infrared radiation. The breakdown of methane in an atmosphere containing oxygen produces carbon monoxide, water vapor and infrared radiation. The carbon monoxide is not stable, so it eventually becomes carbon dioxide and in doing so releases yet more infrared radiation. Water vapor traps more infrared than does carbon dioxide. Hyperthermals through the early Eocene During the warming in the early Eocene between 55 and 52 Ma, there were a series of short-term changes of carbon isotope composition in the ocean. These isotope changes occurred due to the release of carbon from the ocean into the atmosphere that led to a temperature increase of 4–8 °C (7.2–14.4 °F) at the surface of the ocean. These hyperthermals led to increased perturbations in planktonic and benthic foraminifera, with a higher rate of sedimentation as a consequence of the warmer temperatures. Recent analysis of and research into these hyperthermals in the early Eocene has led to hypotheses that the hyperthermals are based on orbital parameters, in particular eccentricity and obliquity. The hyperthermals in the early Eocene, notably the Palaeocene–Eocene Thermal Maximum (PETM), the Eocene Thermal Maximum 2 (ETM2), and the Eocene Thermal Maximum 3 (ETM3), were analyzed and found that orbital control may have had a role in triggering the ETM2 and ETM3. Equable climate problem One of the unique features of the Eocene's climate as mentioned before was the equable and homogeneous climate that existed in the early parts of the Eocene. A multitude of proxies support the presence of a warmer equable climate being present during this period of time. A few of these proxies include the presence of fossils native to warm climates, such as crocodiles, located in the higher latitudes, the presence in the high latitudes of frost-intolerant flora such as palm trees which cannot survive during sustained freezes, and fossils of snakes found in the tropics that would require much higher average temperatures to sustain them. TEX86 BAYSPAR measurements indicate extremely high sea surface temperatures of 40 °C (104 °F) to 45 °C (113 °F) at low latitudes, although clumped isotope analyses point to a maximum low latitude sea surface temperature of 36.3 °C (97.3 °F) ± 1.9 °C (35.4 °F) during the Early Eocene Climatic Optimum. Relative to present-day values, bottom water temperatures are 10 °C (18 °F) higher according to isotope proxies. With these bottom water temperatures, temperatures in areas where deep water forms near the poles are unable to be much cooler than the bottom water temperatures.An issue arises, however, when trying to model the Eocene and reproduce the results that are found with the proxy data. Using all different ranges of greenhouse gasses that occurred during the early Eocene, models were unable to produce the warming that was found at the poles and the reduced seasonality that occurs with winters at the poles being substantially warmer. The models, while accurately predicting the tropics, tend to produce significantly cooler temperatures of up to 20 °C (36 °F) colder than the actual determined temperature at the poles. This error has been classified as the "equable climate problem". To solve this problem, the solution would involve finding a process to warm the poles without warming the tropics. Some hypotheses and tests which attempt to find the process are listed below. Large lakes Due to the nature of water as opposed to land, less temperature variability would be present if a large body of water is also present. In an attempt to try to mitigate the cooling polar temperatures, large lakes were proposed to mitigate seasonal climate changes. To replicate this case, a lake was inserted into North America and a climate model was run using varying carbon dioxide levels. The model runs concluded that while the lake did reduce the seasonality of the region greater than just an increase in carbon dioxide, the addition of a large lake was unable to reduce the seasonality to the levels shown by the floral and faunal data. Ocean heat transport The transport of heat from the tropics to the poles, much like how ocean heat transport functions in modern times, was considered a possibility for the increased temperature and reduced seasonality for the poles. With the increased sea surface temperatures and the increased temperature of the deep ocean water during the early Eocene, one common hypothesis was that due to these increases there would be a greater transport of heat from the tropics to the poles. Simulating these differences, the models produced lower heat transport due to the lower temperature gradients and were unsuccessful in producing an equable climate from only ocean heat transport. Orbital parameters While typically seen as a control on ice growth and seasonality, the orbital parameters were theorized as a possible control on continental temperatures and seasonality. Simulating the Eocene by using an ice free planet, eccentricity, obliquity, and precession were modified in different model runs to determine all the possible different scenarios that could occur and their effects on temperature. One particular case led to warmer winters and cooler summer by up to 30% in the North American continent, and it reduced the seasonal variation of temperature by up to 75%. While orbital parameters did not produce the warming at the poles, the parameters did show a great effect on seasonality and needed to be considered. Polar stratospheric clouds Another method considered for producing the warm polar temperatures were polar stratospheric clouds. Polar stratospheric clouds are clouds that occur in the lower stratosphere at very low temperatures. Polar stratospheric clouds have a great impact on radiative forcing. Due to their minimal albedo properties and their optical thickness, polar stratospheric clouds act similar to a greenhouse gas and traps outgoing longwave radiation. Different types of polar stratospheric clouds occur in the atmosphere: polar stratospheric clouds that are created due to interactions with nitric or sulfuric acid and water (Type I) or polar stratospheric clouds that are created with only water ice (Type II).Methane is an important factor in the creation of the primary Type II polar stratospheric clouds that were created in the early Eocene. Since water vapor is the only supporting substance used in Type II polar stratospheric clouds, the presence of water vapor in the lower stratosphere is necessary where in most situations the presence of water vapor in the lower stratosphere is rare. When methane is oxidized, a significant amount of water vapor is released. Another requirement for polar stratospheric clouds is cold temperatures to ensure condensation and cloud production. Polar stratospheric cloud production, since it requires the cold temperatures, is usually limited to nighttime and winter conditions. With this combination of wetter and colder conditions in the lower stratosphere, polar stratospheric clouds could have formed over wide areas in Polar Regions.To test the polar stratospheric clouds effects on the Eocene climate, models were run comparing the effects of polar stratospheric clouds at the poles to an increase in atmospheric carbon dioxide. The polar stratospheric clouds had a warming effect on the poles, increasing temperatures by up to 20 °C in the winter months. A multitude of feedbacks also occurred in the models due to the polar stratospheric clouds' presence. Any ice growth was slowed immensely and would lead to any present ice melting. Only the poles were affected with the change in temperature and the tropics were unaffected, which with an increase in atmospheric carbon dioxide would also cause the tropics to increase in temperature. Due to the warming of the troposphere from the increased greenhouse effect of the polar stratospheric clouds, the stratosphere would cool and would potentially increase the amount of polar stratospheric clouds. While the polar stratospheric clouds could explain the reduction of the equator to pole temperature gradient and the increased temperatures at the poles during the early Eocene, there are a few drawbacks to maintaining polar stratospheric clouds for an extended period of time. Separate model runs were used to determine the sustainability of the polar stratospheric clouds. It was determined that in order to maintain the lower stratospheric water vapor, methane would need to be continually released and sustained. In addition, the amounts of ice and condensation nuclei would need to be high in order for the polar stratospheric cloud to sustain itself and eventually expand. Middle Eocene The Eocene is not only known for containing the warmest period during the Cenozoic; it also marked the decline into an icehouse climate and the rapid expansion of the Antarctic ice sheet. The transition from a warming climate into a cooling climate began at around 49 Ma. Isotopes of carbon and oxygen indicate a shift to a global cooling climate. The cause of the cooling has been attributed to a significant decrease of >2,000 ppm in atmospheric carbon dioxide concentrations. One proposed cause of the reduction in carbon dioxide during the warming to cooling transition was the azolla event. With the equable climate during the early Eocene, warm temperatures in the arctic allowed for the growth of azolla, which is a floating aquatic fern, on the Arctic Ocean. The significantly high amounts of carbon dioxide also acted to facilitate azolla blooms across the Arctic Ocean. Compared to current carbon dioxide levels, these azolla grew rapidly in the enhanced carbon dioxide levels found in the early Eocene. The isolation of the Arctic Ocean, evidenced by euxinia that occurred at this time, led to stagnant waters and as the azolla sank to the sea floor, they became part of the sediments on the seabed and effectively sequestered the carbon by locking it out of the atmosphere for good. The ability for the azolla to sequester carbon is exceptional, and the enhanced burial of azolla could have had a significant effect on the world atmospheric carbon content and may have been the event to begin the transition into an ice house climate. The azolla event could have led to a draw down of atmospheric carbon dioxide of up to 470 ppm. Assuming the carbon dioxide concentrations were at 900 ppmv prior to the Azolla Event they would have dropped to 430 ppmv, or 30 ppmv more than they are today, after the Azolla Event. This cooling trend at the end of the Early Eocene Climatic Optimum has also been proposed to have been caused by increased siliceous plankton productivity and marine carbon burial, which also helped draw carbon dioxide out of the atmosphere. Cooling after this event continued due to continual decrease in atmospheric carbon dioxide from organic productivity and weathering from mountain building.Global cooling continued until there was a major reversal from cooling to warming in the Bartonian. This warming event, signifying a sudden and temporary reversal of the cooling conditions, is known as the Middle Eocene Climatic Optimum (MECO). At around 41.5 Ma, stable isotopic analysis of samples from Southern Ocean drilling sites indicated a warming event for 600,000 years. A similar shift in carbon isotopes is known from the Northern Hemisphere in the Scaglia Limestones of Italy. Oxygen isotope analysis showed a large negative change in the proportion of heavier oxygen isotopes to lighter oxygen isotopes, which indicates an increase in global temperatures. The warming is considered to be primarily due to carbon dioxide increases, because carbon isotope signatures rule out major methane release during this short-term warming. A sharp increase in atmospheric carbon dioxide was observed with a maximum of 4,000 ppm: the highest amount of atmospheric carbon dioxide detected during the Eocene. Other studies suggest a more modest rise in carbon dioxide levels. The increase in atmospheric carbon dioxide has also been hypothesised to have been driven by increased seafloor spreading rates and metamorphic decarbonation reactions between Australia and Antarctica and increased amounts of volcanism in the region. One possible cause of atmospheric carbon dioxide increase could have been a sudden increase due to metamorphic release due to continental drift and collision of India with Asia and the resulting formation of the Himalayas; however, data on the exact timing of metamorphic release of atmospheric carbon dioxide is not well resolved in the data. Recent studies have mentioned, however, that the removal of the ocean between Asia and India could have released significant amounts of carbon dioxide. Another hypothesis still implicates a diminished negative feedback of silicate weathering as a result of continental rocks having become less weatherable during the warm Early and Middle Eocene, allowing volcanically released carbon dioxide to persist in the atmosphere for longer. Yet another explanation hypothesises that MECO warming was caused by the simultaneous occurrence of minima in both the 400 kyr and 2.4 Myr eccentricity cycles. During the MECO, sea surface temperatures in the Tethys Ocean jumped to 32-36 °C, and Tethyan seawater became more dysoxic. A decline in carbonate accumulation at ocean depths of greater than three kilometres took place synchronously with the peak of the MECO, signifying ocean acidification took place in the deep ocean. An abrupt decrease in lakewater salinity in western North America occurred during this warming interval. This warming is short lived, as benthic oxygen isotope records indicate a return to cooling at ~40 Ma. Late Eocene At the end of the Middle Eocene Climatic Optimum, cooling and the carbon dioxide drawdown continued through the late Eocene and into the Eocene–Oligocene transition around 34 Ma. The post-MECO cooling brought with it a major aridification trend in Asia. The cooling during the initial stages of the opening of the Drake Passage ~38.5 Ma was not global, as evidenced by an absence of cooling in the North Atlantic. During the cooling period, benthic oxygen isotopes show the possibility of ice creation and ice increase during this later cooling. The end of the Eocene and beginning of the Oligocene is marked with the massive expansion of area of the Antarctic ice sheet that was a major step into the icehouse climate. Multiple proxies, such as oxygen isotopes and alkenones, indicate that at the Eocene–Oligocene transition, the atmospheric carbon dioxide concentration had decreased to around 750–800 ppm, approximately twice that of present levels. Along with the decrease of atmospheric carbon dioxide reducing the global temperature, orbital factors in ice creation can be seen with 100,000-year and 400,000-year fluctuations in benthic oxygen isotope records. Another major contribution to the expansion of the ice sheet was the creation of the Antarctic Circumpolar Current. The creation of the Antarctic circumpolar current would isolate the cold water around the Antarctic, which would reduce heat transport to the Antarctic along with creating ocean gyres that result in the upwelling of colder bottom waters. The issue with this hypothesis of the consideration of this being a factor for the Eocene-Oligocene transition is the timing of the creation of the circulation is uncertain. For Drake Passage, sediments indicate the opening occurred ~41 Ma while tectonics indicate that this occurred ~32 Ma. Flora During the early-middle Eocene, forests covered most of the Earth including the poles. Tropical forests extended across much of modern Africa, South America, Central America, India, South-east Asia and China. Paratropical forests grew over North America, Europe and Russia, with broad-leafed evergreen and broad-leafed deciduous forests at higher latitudes.Polar forests were quite extensive. Fossils and even preserved remains of trees such as swamp cypress and dawn redwood from the Eocene have been found on Ellesmere Island in the Arctic. Even at that time, Ellesmere Island was only a few degrees in latitude further south than it is today. Fossils of subtropical and even tropical trees and plants from the Eocene also have been found in Greenland and Alaska. Tropical rainforests grew as far north as northern North America and Europe.Palm trees were growing as far north as Alaska and northern Europe during the early Eocene, although they became less abundant as the climate cooled. Dawn redwoods were far more extensive as well.The earliest definitive Eucalyptus fossils were dated from 51.9 Mya, and were found in the Laguna del Hunco deposit in Chubut province in Argentina.Cooling began mid-period, and by the end of the Eocene continental interiors had begun to dry, with forests thinning considerably in some areas. The newly evolved grasses were still confined to river banks and lake shores, and had not yet expanded into plains and savannas.The cooling also brought seasonal changes. Deciduous trees, better able to cope with large temperature changes, began to overtake evergreen tropical species. By the end of the period, deciduous forests covered large parts of the northern continents, including North America, Eurasia and the Arctic, and rainforests held on only in equatorial South America, Africa, India and Australia.Antarctica began the Eocene fringed with a warm temperate to sub-tropical rainforest. Pollen found in Prydz Bay from the Eocene suggest taiga forest existed there. It became much colder as the period progressed; the heat-loving tropical flora was wiped out, and by the beginning of the Oligocene, the continent hosted deciduous forests and vast stretches of tundra. Fauna During the Eocene, plants and marine faunas became quite modern. Many modern bird orders first appeared in the Eocene. The Eocene oceans were warm and teeming with fish and other sea life. Mammals The oldest known fossils of most of the modern mammal orders appear within a brief period during the early Eocene. At the beginning of the Eocene, several new mammal groups arrived in North America. These modern mammals, like artiodactyls, perissodactyls, and primates, had features like long, thin legs, feet, and hands capable of grasping, as well as differentiated teeth adapted for chewing. Dwarf forms reigned. All the members of the new mammal orders were small, under 10 kg; based on comparisons of tooth size, Eocene mammals were only 60% of the size of the primitive Palaeocene mammals that preceded them. They were also smaller than the mammals that followed them. It is assumed that the hot Eocene temperatures favored smaller animals that were better able to manage the heat.Both groups of modern ungulates (hoofed animals) became prevalent because of a major radiation between Europe and North America, along with carnivorous ungulates like Mesonyx. Early forms of many other modern mammalian orders appeared, including horses (most notably the Eohippus), bats, proboscidians (elephants), primates, rodents, and marsupials. Older primitive forms of mammals declined in variety and importance. Important Eocene land fauna fossil remains have been found in western North America, Europe, Patagonia, Egypt, and southeast Asia. Marine fauna are best known from South Asia and the southeast United States.Established megafauna of the Eocene include the Uintatherium, Arsinoitherium, and brontotheres, in which the former two, unlike the latter, did not belong to ungulates but groups that became extinct shortly after their establishments. Large terrestrial mammalian predators began to take form as the terrestrial carnivores like the Hyaenodon and Daphoenus (the earliest lineage of a once-successful predatory family known as bear dogs). Entelodonts meanwhile established themselves as some of the largest omnivores. The first nimravids, including Dinictis, established themselves as amongst the first feliforms to appear. Their groups became highly successful and continued to live past the Eocene. Basilosaurus is a very well-known Eocene whale, but whales as a group had become very diverse during the Eocene, which is when the major transitions from being terrestrial to fully aquatic in cetaceans occurred. The first sirenians were evolving at this time, and would eventually evolve into the extant manatees and dugongs. It is thought that millions of years after the Cretaceous-Paleogene extinction event, brain sizes of mammals now started to increase, "likely driven by a need for greater cognition in increasingly complex environments". Birds Eocene birds include some enigmatic groups with resemblances to modern forms, some of which continued from the Paleocene. Bird taxa of the Eocene include carnivorous psittaciforms, such as Messelasturidae, Halcyornithidae, large flightless forms such as Gastornis and Eleutherornis, long legged falcon Masillaraptor, ancient galliforms such as Gallinuloides, putative rail relatives of the family Songziidae, various pseudotooth birds such as Gigantornis, the ibis relative Rhynchaeites, primitive swifts of the genus Aegialornis, and primitive penguins such as Archaeospheniscus and Inkayacu. Reptiles Reptile fossils from this time, such as fossils of pythons and turtles, are abundant. Insects and arachnids Several rich fossil insect faunas are known from the Eocene, notably the Baltic amber found mainly along the south coast of the Baltic Sea, amber from the Paris Basin, France, the Fur Formation, Denmark, and the Bembridge Marls from the Isle of Wight, England. Insects found in Eocene deposits mostly belong to genera that exist today, though their range has often shifted since the Eocene. For instance the bibionid genus Plecia is common in fossil faunas from presently temperate areas, but only lives in the tropics and subtropics today. Gallery See also Bolca in Italy List of fossil sites (with link directory) London Clay Messel pit in Germany Wadi El Hitan in Egypt Notes References Further reading Ogg, Jim; June, 2004, Overview of Global Boundary Stratotype Sections and Points (GSSP's) Global Stratotype Sections and Points Accessed April 30, 2006. Stanley, Steven M. Earth System History. New York: W.H. Freeman and Company, 1999. ISBN 0-7167-2882-6 External links PaleoMap Project Paleos Eocene page PBS Deep Time: Eocene Eocene and Oligocene Fossils The UPenn Fossil Forest Project, focusing on the Eocene polar forests in Ellesmere Island, Canada Basilosaurus Primitive Eocene Whales Basilosaurus - The plesiosaur that wasn't.... Detailed maps of Tertiary Western North America Map of Eocene Earth Eocene Microfossils: 60+ images of Foraminifera Eocene Epoch. (2011). In Encyclopædia Britannica. Retrieved from Eocene Epoch \| geochronology	follows	{ "answer_start": [ 10500 ], "text": [ "Palaeocene" ] }
The Eocene (IPA: EE-ə-seen, EE-oh-) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name Eocene comes from the Ancient Greek ἠώς (ēṓs, "dawn") and καινός (kainós, "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the Grande Coupure (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the epoch are well identified, though their exact dates are slightly uncertain. Etymology The term "Eocene" is derived from Ancient Greek ἠώς eos meaning "dawn", and καινός kainos meaning "new" or "recent", as the epoch saw the dawn of recent, or modern, life. Scottish geologist Charles Lyell (ignoring the Quaternary) had divided the Tertiary Epoch into the Eocene, Miocene, Pliocene, and New Pliocene (Holocene) Periods in 1833. British geologist John Phillips had proposed the Cenozoic in 1840 in place of the Tertiary, and Austrian paleontologist Moritz Hörnes had introduced the Paleogene for the Eocene and Neogene for the Miocene and Pliocene in 1853. After decades of inconsistent usage, the newly formed International Commission on Stratigraphy (ICS), in 1969, standardized stratigraphy based on the prevailing opinions in Europe: the Cenozoic Era subdivided into the Tertiary and Quaternary sub-eras, and the Tertiary subdivided into the Paleogene and Neogene periods. In 1978, the Paleogene was officially defined as the Paleocene, Eocene, and Oligocene epochs; and the Neogene as the Miocene and Pliocene epochs. In 1989, Tertiary and Quaternary were removed from the time scale due to the arbitrary nature of their boundary, but Quaternary was reinstated in 2009. Geology Boundaries The beginning of the Eocene is marked by the Paleocene–Eocene Thermal Maximum, a short period of intense warming and ocean acidification brought about by the release of carbon en masse into the atmosphere and ocean systems, which led to a mass extinction of 30–50% of benthic foraminifera–single-celled species which are used as bioindicators of the health of a marine ecosystem—one of the largest in the Cenozoic. This event happened around 55.8 mya, and was one of the most significant periods of global change during the Cenozoic.The end of the Eocene was marked by the Eocene–Oligocene extinction event, also known as the Grande Coupure. Stratigraphy The Eocene is conventionally divided into early (56–47.8 Ma), middle (47.8–38 Ma), and late (38–33.9 Ma) subdivisions. The corresponding rocks are referred to as lower, middle, and upper Eocene. The Ypresian Stage constitutes the lower, the Priabonian Stage the upper; and the Lutetian and Bartonian stages are united as the middle Eocene. Palaeogeography and tectonics During the Eocene, the continents continued to drift toward their present positions. At the beginning of the period, Australia and Antarctica remained connected, and warm equatorial currents may have mixed with colder Antarctic waters, distributing the heat around the planet and keeping global temperatures high. When Australia split from the southern continent around 45 Ma, the warm equatorial currents were routed away from Antarctica. An isolated cold water channel developed between the two continents. However, modeling results call into question the thermal isolation model for late Eocene cooling, and decreasing carbon dioxide levels in the atmosphere may have been more important. Once the Antarctic region began to cool down, the ocean surrounding Antarctica began to freeze, sending cold water and icefloes north and reinforcing the cooling.The northern supercontinent of Laurasia began to fragment, as Europe, Greenland and North America drifted apart.In western North America, the Laramide Orogeny came to an end in the Eocene, and compression was replaced with crustal extension that ultimately gave rise to the Basin and Range Province. Huge lakes formed in the high flat basins among uplifts, resulting in the deposition of the Green River Formation lagerstätte.At about 35 Ma, an asteroid impact on the eastern coast of North America formed the Chesapeake Bay impact crater.In Europe, the Tethys Sea finally disappeared, while the uplift of the Alps isolated its final remnant, the Mediterranean, and created another shallow sea with island archipelagos to the north. Though the North Atlantic was opening, a land connection appears to have remained between North America and Europe since the faunas of the two regions are very similar.Eurasia was separated in three different landmasses 50 Ma; Western Europe, Balkanatolia and Asia. About 40 Ma, Balkanatolia and Asia were connected, while Europe was connected 34 Ma.India collided with Asia, folding to initiate formation of the Himalayas. India collided with the Kohistan–Ladakh Arc around 50.2 Ma and with Karakoram around 40.4 Ma, with the final collision between Asia and India occurring ~40 Ma. Climate The Eocene Epoch contained a wide variety of different climate conditions that includes the warmest climate in the Cenozoic Era, and arguably the warmest time interval since the Permian-Triassic mass extinction and Early Triassic, and ends in an icehouse climate. The evolution of the Eocene climate began with warming after the end of the Paleocene–Eocene Thermal Maximum (PETM) at 56 Ma to a maximum during the Eocene Optimum at around 49 Ma. Recent study show elevation-dependent temperature changes during the Eocene hothouse. During this period of time, little to no ice was present on Earth with a smaller difference in temperature from the equator to the poles. Because of this the maximum sea level was 150 meters higher than current levels. Following the maximum was a descent into an icehouse climate from the Eocene Optimum to the Eocene-Oligocene transition at 34 Ma. During this decrease, ice began to reappear at the poles, and the Eocene-Oligocene transition is the period of time where the Antarctic ice sheet began to rapidly expand. Early Eocene Greenhouse gases, in particular carbon dioxide and methane, played a significant role during the Eocene in controlling the surface temperature. The end of the PETM was met with very large sequestration of carbon dioxide into the forms of methane clathrate, coal, and crude oil at the bottom of the Arctic Ocean, that reduced the atmospheric carbon dioxide. This event was similar in magnitude to the massive release of greenhouse gasses at the beginning of the PETM, and it is hypothesized that the sequestration was mainly due to organic carbon burial and weathering of silicates. For the early Eocene there is much discussion on how much carbon dioxide was in the atmosphere. This is due to numerous proxies representing different atmospheric carbon dioxide content. For example, diverse geochemical and paleontological proxies indicate that at the maximum of global warmth the atmospheric carbon dioxide values were at 700–900 ppm while other proxies such as pedogenic (soil building) carbonate and marine boron isotopes indicate large changes of carbon dioxide of over 2,000 ppm over periods of time of less than 1 million years. Sources for this large influx of carbon dioxide could be attributed to volcanic out-gassing due to North Atlantic rifting or oxidation of methane stored in large reservoirs deposited from the PETM event in the sea floor or wetland environments. For contrast, today the carbon dioxide levels are at 400 ppm or 0.04%. At about the beginning of the Eocene Epoch (55.8–33.9 Ma) the amount of oxygen in the earth's atmosphere more or less doubled.During the early Eocene, methane was another greenhouse gas that had a drastic effect on the climate. The warming effect of one ton of methane dimensions unspecified is approximately 30 times the warming effect of one ton of carbon on a 100-year scale (i.e., methane has a global warming potential of 29.8±11). Most of the methane released to the atmosphere during this period of time would have been from wetlands, swamps, and forests. The atmospheric methane concentration today is 0.000179% or 1.79 ppmv. As a result of the warmer climate and the sea level rise associated with the early Eocene, more wetlands, more forests, and more coal deposits would have been available for methane release. If we compare the early Eocene production of methane to current levels of atmospheric methane, the early Eocene would have produced triple the amount of methane. The warm temperatures during the early Eocene could have increased methane production rates, and methane that is released into the atmosphere would in turn warm the troposphere, cool the stratosphere, and produce water vapor and carbon dioxide through oxidation. Biogenic production of methane produces carbon dioxide and water vapor along with the methane, as well as yielding infrared radiation. The breakdown of methane in an atmosphere containing oxygen produces carbon monoxide, water vapor and infrared radiation. The carbon monoxide is not stable, so it eventually becomes carbon dioxide and in doing so releases yet more infrared radiation. Water vapor traps more infrared than does carbon dioxide. Hyperthermals through the early Eocene During the warming in the early Eocene between 55 and 52 Ma, there were a series of short-term changes of carbon isotope composition in the ocean. These isotope changes occurred due to the release of carbon from the ocean into the atmosphere that led to a temperature increase of 4–8 °C (7.2–14.4 °F) at the surface of the ocean. These hyperthermals led to increased perturbations in planktonic and benthic foraminifera, with a higher rate of sedimentation as a consequence of the warmer temperatures. Recent analysis of and research into these hyperthermals in the early Eocene has led to hypotheses that the hyperthermals are based on orbital parameters, in particular eccentricity and obliquity. The hyperthermals in the early Eocene, notably the Palaeocene–Eocene Thermal Maximum (PETM), the Eocene Thermal Maximum 2 (ETM2), and the Eocene Thermal Maximum 3 (ETM3), were analyzed and found that orbital control may have had a role in triggering the ETM2 and ETM3. Equable climate problem One of the unique features of the Eocene's climate as mentioned before was the equable and homogeneous climate that existed in the early parts of the Eocene. A multitude of proxies support the presence of a warmer equable climate being present during this period of time. A few of these proxies include the presence of fossils native to warm climates, such as crocodiles, located in the higher latitudes, the presence in the high latitudes of frost-intolerant flora such as palm trees which cannot survive during sustained freezes, and fossils of snakes found in the tropics that would require much higher average temperatures to sustain them. TEX86 BAYSPAR measurements indicate extremely high sea surface temperatures of 40 °C (104 °F) to 45 °C (113 °F) at low latitudes, although clumped isotope analyses point to a maximum low latitude sea surface temperature of 36.3 °C (97.3 °F) ± 1.9 °C (35.4 °F) during the Early Eocene Climatic Optimum. Relative to present-day values, bottom water temperatures are 10 °C (18 °F) higher according to isotope proxies. With these bottom water temperatures, temperatures in areas where deep water forms near the poles are unable to be much cooler than the bottom water temperatures.An issue arises, however, when trying to model the Eocene and reproduce the results that are found with the proxy data. Using all different ranges of greenhouse gasses that occurred during the early Eocene, models were unable to produce the warming that was found at the poles and the reduced seasonality that occurs with winters at the poles being substantially warmer. The models, while accurately predicting the tropics, tend to produce significantly cooler temperatures of up to 20 °C (36 °F) colder than the actual determined temperature at the poles. This error has been classified as the "equable climate problem". To solve this problem, the solution would involve finding a process to warm the poles without warming the tropics. Some hypotheses and tests which attempt to find the process are listed below. Large lakes Due to the nature of water as opposed to land, less temperature variability would be present if a large body of water is also present. In an attempt to try to mitigate the cooling polar temperatures, large lakes were proposed to mitigate seasonal climate changes. To replicate this case, a lake was inserted into North America and a climate model was run using varying carbon dioxide levels. The model runs concluded that while the lake did reduce the seasonality of the region greater than just an increase in carbon dioxide, the addition of a large lake was unable to reduce the seasonality to the levels shown by the floral and faunal data. Ocean heat transport The transport of heat from the tropics to the poles, much like how ocean heat transport functions in modern times, was considered a possibility for the increased temperature and reduced seasonality for the poles. With the increased sea surface temperatures and the increased temperature of the deep ocean water during the early Eocene, one common hypothesis was that due to these increases there would be a greater transport of heat from the tropics to the poles. Simulating these differences, the models produced lower heat transport due to the lower temperature gradients and were unsuccessful in producing an equable climate from only ocean heat transport. Orbital parameters While typically seen as a control on ice growth and seasonality, the orbital parameters were theorized as a possible control on continental temperatures and seasonality. Simulating the Eocene by using an ice free planet, eccentricity, obliquity, and precession were modified in different model runs to determine all the possible different scenarios that could occur and their effects on temperature. One particular case led to warmer winters and cooler summer by up to 30% in the North American continent, and it reduced the seasonal variation of temperature by up to 75%. While orbital parameters did not produce the warming at the poles, the parameters did show a great effect on seasonality and needed to be considered. Polar stratospheric clouds Another method considered for producing the warm polar temperatures were polar stratospheric clouds. Polar stratospheric clouds are clouds that occur in the lower stratosphere at very low temperatures. Polar stratospheric clouds have a great impact on radiative forcing. Due to their minimal albedo properties and their optical thickness, polar stratospheric clouds act similar to a greenhouse gas and traps outgoing longwave radiation. Different types of polar stratospheric clouds occur in the atmosphere: polar stratospheric clouds that are created due to interactions with nitric or sulfuric acid and water (Type I) or polar stratospheric clouds that are created with only water ice (Type II).Methane is an important factor in the creation of the primary Type II polar stratospheric clouds that were created in the early Eocene. Since water vapor is the only supporting substance used in Type II polar stratospheric clouds, the presence of water vapor in the lower stratosphere is necessary where in most situations the presence of water vapor in the lower stratosphere is rare. When methane is oxidized, a significant amount of water vapor is released. Another requirement for polar stratospheric clouds is cold temperatures to ensure condensation and cloud production. Polar stratospheric cloud production, since it requires the cold temperatures, is usually limited to nighttime and winter conditions. With this combination of wetter and colder conditions in the lower stratosphere, polar stratospheric clouds could have formed over wide areas in Polar Regions.To test the polar stratospheric clouds effects on the Eocene climate, models were run comparing the effects of polar stratospheric clouds at the poles to an increase in atmospheric carbon dioxide. The polar stratospheric clouds had a warming effect on the poles, increasing temperatures by up to 20 °C in the winter months. A multitude of feedbacks also occurred in the models due to the polar stratospheric clouds' presence. Any ice growth was slowed immensely and would lead to any present ice melting. Only the poles were affected with the change in temperature and the tropics were unaffected, which with an increase in atmospheric carbon dioxide would also cause the tropics to increase in temperature. Due to the warming of the troposphere from the increased greenhouse effect of the polar stratospheric clouds, the stratosphere would cool and would potentially increase the amount of polar stratospheric clouds. While the polar stratospheric clouds could explain the reduction of the equator to pole temperature gradient and the increased temperatures at the poles during the early Eocene, there are a few drawbacks to maintaining polar stratospheric clouds for an extended period of time. Separate model runs were used to determine the sustainability of the polar stratospheric clouds. It was determined that in order to maintain the lower stratospheric water vapor, methane would need to be continually released and sustained. In addition, the amounts of ice and condensation nuclei would need to be high in order for the polar stratospheric cloud to sustain itself and eventually expand. Middle Eocene The Eocene is not only known for containing the warmest period during the Cenozoic; it also marked the decline into an icehouse climate and the rapid expansion of the Antarctic ice sheet. The transition from a warming climate into a cooling climate began at around 49 Ma. Isotopes of carbon and oxygen indicate a shift to a global cooling climate. The cause of the cooling has been attributed to a significant decrease of >2,000 ppm in atmospheric carbon dioxide concentrations. One proposed cause of the reduction in carbon dioxide during the warming to cooling transition was the azolla event. With the equable climate during the early Eocene, warm temperatures in the arctic allowed for the growth of azolla, which is a floating aquatic fern, on the Arctic Ocean. The significantly high amounts of carbon dioxide also acted to facilitate azolla blooms across the Arctic Ocean. Compared to current carbon dioxide levels, these azolla grew rapidly in the enhanced carbon dioxide levels found in the early Eocene. The isolation of the Arctic Ocean, evidenced by euxinia that occurred at this time, led to stagnant waters and as the azolla sank to the sea floor, they became part of the sediments on the seabed and effectively sequestered the carbon by locking it out of the atmosphere for good. The ability for the azolla to sequester carbon is exceptional, and the enhanced burial of azolla could have had a significant effect on the world atmospheric carbon content and may have been the event to begin the transition into an ice house climate. The azolla event could have led to a draw down of atmospheric carbon dioxide of up to 470 ppm. Assuming the carbon dioxide concentrations were at 900 ppmv prior to the Azolla Event they would have dropped to 430 ppmv, or 30 ppmv more than they are today, after the Azolla Event. This cooling trend at the end of the Early Eocene Climatic Optimum has also been proposed to have been caused by increased siliceous plankton productivity and marine carbon burial, which also helped draw carbon dioxide out of the atmosphere. Cooling after this event continued due to continual decrease in atmospheric carbon dioxide from organic productivity and weathering from mountain building.Global cooling continued until there was a major reversal from cooling to warming in the Bartonian. This warming event, signifying a sudden and temporary reversal of the cooling conditions, is known as the Middle Eocene Climatic Optimum (MECO). At around 41.5 Ma, stable isotopic analysis of samples from Southern Ocean drilling sites indicated a warming event for 600,000 years. A similar shift in carbon isotopes is known from the Northern Hemisphere in the Scaglia Limestones of Italy. Oxygen isotope analysis showed a large negative change in the proportion of heavier oxygen isotopes to lighter oxygen isotopes, which indicates an increase in global temperatures. The warming is considered to be primarily due to carbon dioxide increases, because carbon isotope signatures rule out major methane release during this short-term warming. A sharp increase in atmospheric carbon dioxide was observed with a maximum of 4,000 ppm: the highest amount of atmospheric carbon dioxide detected during the Eocene. Other studies suggest a more modest rise in carbon dioxide levels. The increase in atmospheric carbon dioxide has also been hypothesised to have been driven by increased seafloor spreading rates and metamorphic decarbonation reactions between Australia and Antarctica and increased amounts of volcanism in the region. One possible cause of atmospheric carbon dioxide increase could have been a sudden increase due to metamorphic release due to continental drift and collision of India with Asia and the resulting formation of the Himalayas; however, data on the exact timing of metamorphic release of atmospheric carbon dioxide is not well resolved in the data. Recent studies have mentioned, however, that the removal of the ocean between Asia and India could have released significant amounts of carbon dioxide. Another hypothesis still implicates a diminished negative feedback of silicate weathering as a result of continental rocks having become less weatherable during the warm Early and Middle Eocene, allowing volcanically released carbon dioxide to persist in the atmosphere for longer. Yet another explanation hypothesises that MECO warming was caused by the simultaneous occurrence of minima in both the 400 kyr and 2.4 Myr eccentricity cycles. During the MECO, sea surface temperatures in the Tethys Ocean jumped to 32-36 °C, and Tethyan seawater became more dysoxic. A decline in carbonate accumulation at ocean depths of greater than three kilometres took place synchronously with the peak of the MECO, signifying ocean acidification took place in the deep ocean. An abrupt decrease in lakewater salinity in western North America occurred during this warming interval. This warming is short lived, as benthic oxygen isotope records indicate a return to cooling at ~40 Ma. Late Eocene At the end of the Middle Eocene Climatic Optimum, cooling and the carbon dioxide drawdown continued through the late Eocene and into the Eocene–Oligocene transition around 34 Ma. The post-MECO cooling brought with it a major aridification trend in Asia. The cooling during the initial stages of the opening of the Drake Passage ~38.5 Ma was not global, as evidenced by an absence of cooling in the North Atlantic. During the cooling period, benthic oxygen isotopes show the possibility of ice creation and ice increase during this later cooling. The end of the Eocene and beginning of the Oligocene is marked with the massive expansion of area of the Antarctic ice sheet that was a major step into the icehouse climate. Multiple proxies, such as oxygen isotopes and alkenones, indicate that at the Eocene–Oligocene transition, the atmospheric carbon dioxide concentration had decreased to around 750–800 ppm, approximately twice that of present levels. Along with the decrease of atmospheric carbon dioxide reducing the global temperature, orbital factors in ice creation can be seen with 100,000-year and 400,000-year fluctuations in benthic oxygen isotope records. Another major contribution to the expansion of the ice sheet was the creation of the Antarctic Circumpolar Current. The creation of the Antarctic circumpolar current would isolate the cold water around the Antarctic, which would reduce heat transport to the Antarctic along with creating ocean gyres that result in the upwelling of colder bottom waters. The issue with this hypothesis of the consideration of this being a factor for the Eocene-Oligocene transition is the timing of the creation of the circulation is uncertain. For Drake Passage, sediments indicate the opening occurred ~41 Ma while tectonics indicate that this occurred ~32 Ma. Flora During the early-middle Eocene, forests covered most of the Earth including the poles. Tropical forests extended across much of modern Africa, South America, Central America, India, South-east Asia and China. Paratropical forests grew over North America, Europe and Russia, with broad-leafed evergreen and broad-leafed deciduous forests at higher latitudes.Polar forests were quite extensive. Fossils and even preserved remains of trees such as swamp cypress and dawn redwood from the Eocene have been found on Ellesmere Island in the Arctic. Even at that time, Ellesmere Island was only a few degrees in latitude further south than it is today. Fossils of subtropical and even tropical trees and plants from the Eocene also have been found in Greenland and Alaska. Tropical rainforests grew as far north as northern North America and Europe.Palm trees were growing as far north as Alaska and northern Europe during the early Eocene, although they became less abundant as the climate cooled. Dawn redwoods were far more extensive as well.The earliest definitive Eucalyptus fossils were dated from 51.9 Mya, and were found in the Laguna del Hunco deposit in Chubut province in Argentina.Cooling began mid-period, and by the end of the Eocene continental interiors had begun to dry, with forests thinning considerably in some areas. The newly evolved grasses were still confined to river banks and lake shores, and had not yet expanded into plains and savannas.The cooling also brought seasonal changes. Deciduous trees, better able to cope with large temperature changes, began to overtake evergreen tropical species. By the end of the period, deciduous forests covered large parts of the northern continents, including North America, Eurasia and the Arctic, and rainforests held on only in equatorial South America, Africa, India and Australia.Antarctica began the Eocene fringed with a warm temperate to sub-tropical rainforest. Pollen found in Prydz Bay from the Eocene suggest taiga forest existed there. It became much colder as the period progressed; the heat-loving tropical flora was wiped out, and by the beginning of the Oligocene, the continent hosted deciduous forests and vast stretches of tundra. Fauna During the Eocene, plants and marine faunas became quite modern. Many modern bird orders first appeared in the Eocene. The Eocene oceans were warm and teeming with fish and other sea life. Mammals The oldest known fossils of most of the modern mammal orders appear within a brief period during the early Eocene. At the beginning of the Eocene, several new mammal groups arrived in North America. These modern mammals, like artiodactyls, perissodactyls, and primates, had features like long, thin legs, feet, and hands capable of grasping, as well as differentiated teeth adapted for chewing. Dwarf forms reigned. All the members of the new mammal orders were small, under 10 kg; based on comparisons of tooth size, Eocene mammals were only 60% of the size of the primitive Palaeocene mammals that preceded them. They were also smaller than the mammals that followed them. It is assumed that the hot Eocene temperatures favored smaller animals that were better able to manage the heat.Both groups of modern ungulates (hoofed animals) became prevalent because of a major radiation between Europe and North America, along with carnivorous ungulates like Mesonyx. Early forms of many other modern mammalian orders appeared, including horses (most notably the Eohippus), bats, proboscidians (elephants), primates, rodents, and marsupials. Older primitive forms of mammals declined in variety and importance. Important Eocene land fauna fossil remains have been found in western North America, Europe, Patagonia, Egypt, and southeast Asia. Marine fauna are best known from South Asia and the southeast United States.Established megafauna of the Eocene include the Uintatherium, Arsinoitherium, and brontotheres, in which the former two, unlike the latter, did not belong to ungulates but groups that became extinct shortly after their establishments. Large terrestrial mammalian predators began to take form as the terrestrial carnivores like the Hyaenodon and Daphoenus (the earliest lineage of a once-successful predatory family known as bear dogs). Entelodonts meanwhile established themselves as some of the largest omnivores. The first nimravids, including Dinictis, established themselves as amongst the first feliforms to appear. Their groups became highly successful and continued to live past the Eocene. Basilosaurus is a very well-known Eocene whale, but whales as a group had become very diverse during the Eocene, which is when the major transitions from being terrestrial to fully aquatic in cetaceans occurred. The first sirenians were evolving at this time, and would eventually evolve into the extant manatees and dugongs. It is thought that millions of years after the Cretaceous-Paleogene extinction event, brain sizes of mammals now started to increase, "likely driven by a need for greater cognition in increasingly complex environments". Birds Eocene birds include some enigmatic groups with resemblances to modern forms, some of which continued from the Paleocene. Bird taxa of the Eocene include carnivorous psittaciforms, such as Messelasturidae, Halcyornithidae, large flightless forms such as Gastornis and Eleutherornis, long legged falcon Masillaraptor, ancient galliforms such as Gallinuloides, putative rail relatives of the family Songziidae, various pseudotooth birds such as Gigantornis, the ibis relative Rhynchaeites, primitive swifts of the genus Aegialornis, and primitive penguins such as Archaeospheniscus and Inkayacu. Reptiles Reptile fossils from this time, such as fossils of pythons and turtles, are abundant. Insects and arachnids Several rich fossil insect faunas are known from the Eocene, notably the Baltic amber found mainly along the south coast of the Baltic Sea, amber from the Paris Basin, France, the Fur Formation, Denmark, and the Bembridge Marls from the Isle of Wight, England. Insects found in Eocene deposits mostly belong to genera that exist today, though their range has often shifted since the Eocene. For instance the bibionid genus Plecia is common in fossil faunas from presently temperate areas, but only lives in the tropics and subtropics today. Gallery See also Bolca in Italy List of fossil sites (with link directory) London Clay Messel pit in Germany Wadi El Hitan in Egypt Notes References Further reading Ogg, Jim; June, 2004, Overview of Global Boundary Stratotype Sections and Points (GSSP's) Global Stratotype Sections and Points Accessed April 30, 2006. Stanley, Steven M. Earth System History. New York: W.H. Freeman and Company, 1999. ISBN 0-7167-2882-6 External links PaleoMap Project Paleos Eocene page PBS Deep Time: Eocene Eocene and Oligocene Fossils The UPenn Fossil Forest Project, focusing on the Eocene polar forests in Ellesmere Island, Canada Basilosaurus Primitive Eocene Whales Basilosaurus - The plesiosaur that wasn't.... Detailed maps of Tertiary Western North America Map of Eocene Earth Eocene Microfossils: 60+ images of Foraminifera Eocene Epoch. (2011). In Encyclopædia Britannica. Retrieved from Eocene Epoch \| geochronology	followed by	{ "answer_start": [ 454 ], "text": [ "Oligocene" ] }
The Eocene (IPA: EE-ə-seen, EE-oh-) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name Eocene comes from the Ancient Greek ἠώς (ēṓs, "dawn") and καινός (kainós, "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the Grande Coupure (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the epoch are well identified, though their exact dates are slightly uncertain. Etymology The term "Eocene" is derived from Ancient Greek ἠώς eos meaning "dawn", and καινός kainos meaning "new" or "recent", as the epoch saw the dawn of recent, or modern, life. Scottish geologist Charles Lyell (ignoring the Quaternary) had divided the Tertiary Epoch into the Eocene, Miocene, Pliocene, and New Pliocene (Holocene) Periods in 1833. British geologist John Phillips had proposed the Cenozoic in 1840 in place of the Tertiary, and Austrian paleontologist Moritz Hörnes had introduced the Paleogene for the Eocene and Neogene for the Miocene and Pliocene in 1853. After decades of inconsistent usage, the newly formed International Commission on Stratigraphy (ICS), in 1969, standardized stratigraphy based on the prevailing opinions in Europe: the Cenozoic Era subdivided into the Tertiary and Quaternary sub-eras, and the Tertiary subdivided into the Paleogene and Neogene periods. In 1978, the Paleogene was officially defined as the Paleocene, Eocene, and Oligocene epochs; and the Neogene as the Miocene and Pliocene epochs. In 1989, Tertiary and Quaternary were removed from the time scale due to the arbitrary nature of their boundary, but Quaternary was reinstated in 2009. Geology Boundaries The beginning of the Eocene is marked by the Paleocene–Eocene Thermal Maximum, a short period of intense warming and ocean acidification brought about by the release of carbon en masse into the atmosphere and ocean systems, which led to a mass extinction of 30–50% of benthic foraminifera–single-celled species which are used as bioindicators of the health of a marine ecosystem—one of the largest in the Cenozoic. This event happened around 55.8 mya, and was one of the most significant periods of global change during the Cenozoic.The end of the Eocene was marked by the Eocene–Oligocene extinction event, also known as the Grande Coupure. Stratigraphy The Eocene is conventionally divided into early (56–47.8 Ma), middle (47.8–38 Ma), and late (38–33.9 Ma) subdivisions. The corresponding rocks are referred to as lower, middle, and upper Eocene. The Ypresian Stage constitutes the lower, the Priabonian Stage the upper; and the Lutetian and Bartonian stages are united as the middle Eocene. Palaeogeography and tectonics During the Eocene, the continents continued to drift toward their present positions. At the beginning of the period, Australia and Antarctica remained connected, and warm equatorial currents may have mixed with colder Antarctic waters, distributing the heat around the planet and keeping global temperatures high. When Australia split from the southern continent around 45 Ma, the warm equatorial currents were routed away from Antarctica. An isolated cold water channel developed between the two continents. However, modeling results call into question the thermal isolation model for late Eocene cooling, and decreasing carbon dioxide levels in the atmosphere may have been more important. Once the Antarctic region began to cool down, the ocean surrounding Antarctica began to freeze, sending cold water and icefloes north and reinforcing the cooling.The northern supercontinent of Laurasia began to fragment, as Europe, Greenland and North America drifted apart.In western North America, the Laramide Orogeny came to an end in the Eocene, and compression was replaced with crustal extension that ultimately gave rise to the Basin and Range Province. Huge lakes formed in the high flat basins among uplifts, resulting in the deposition of the Green River Formation lagerstätte.At about 35 Ma, an asteroid impact on the eastern coast of North America formed the Chesapeake Bay impact crater.In Europe, the Tethys Sea finally disappeared, while the uplift of the Alps isolated its final remnant, the Mediterranean, and created another shallow sea with island archipelagos to the north. Though the North Atlantic was opening, a land connection appears to have remained between North America and Europe since the faunas of the two regions are very similar.Eurasia was separated in three different landmasses 50 Ma; Western Europe, Balkanatolia and Asia. About 40 Ma, Balkanatolia and Asia were connected, while Europe was connected 34 Ma.India collided with Asia, folding to initiate formation of the Himalayas. India collided with the Kohistan–Ladakh Arc around 50.2 Ma and with Karakoram around 40.4 Ma, with the final collision between Asia and India occurring ~40 Ma. Climate The Eocene Epoch contained a wide variety of different climate conditions that includes the warmest climate in the Cenozoic Era, and arguably the warmest time interval since the Permian-Triassic mass extinction and Early Triassic, and ends in an icehouse climate. The evolution of the Eocene climate began with warming after the end of the Paleocene–Eocene Thermal Maximum (PETM) at 56 Ma to a maximum during the Eocene Optimum at around 49 Ma. Recent study show elevation-dependent temperature changes during the Eocene hothouse. During this period of time, little to no ice was present on Earth with a smaller difference in temperature from the equator to the poles. Because of this the maximum sea level was 150 meters higher than current levels. Following the maximum was a descent into an icehouse climate from the Eocene Optimum to the Eocene-Oligocene transition at 34 Ma. During this decrease, ice began to reappear at the poles, and the Eocene-Oligocene transition is the period of time where the Antarctic ice sheet began to rapidly expand. Early Eocene Greenhouse gases, in particular carbon dioxide and methane, played a significant role during the Eocene in controlling the surface temperature. The end of the PETM was met with very large sequestration of carbon dioxide into the forms of methane clathrate, coal, and crude oil at the bottom of the Arctic Ocean, that reduced the atmospheric carbon dioxide. This event was similar in magnitude to the massive release of greenhouse gasses at the beginning of the PETM, and it is hypothesized that the sequestration was mainly due to organic carbon burial and weathering of silicates. For the early Eocene there is much discussion on how much carbon dioxide was in the atmosphere. This is due to numerous proxies representing different atmospheric carbon dioxide content. For example, diverse geochemical and paleontological proxies indicate that at the maximum of global warmth the atmospheric carbon dioxide values were at 700–900 ppm while other proxies such as pedogenic (soil building) carbonate and marine boron isotopes indicate large changes of carbon dioxide of over 2,000 ppm over periods of time of less than 1 million years. Sources for this large influx of carbon dioxide could be attributed to volcanic out-gassing due to North Atlantic rifting or oxidation of methane stored in large reservoirs deposited from the PETM event in the sea floor or wetland environments. For contrast, today the carbon dioxide levels are at 400 ppm or 0.04%. At about the beginning of the Eocene Epoch (55.8–33.9 Ma) the amount of oxygen in the earth's atmosphere more or less doubled.During the early Eocene, methane was another greenhouse gas that had a drastic effect on the climate. The warming effect of one ton of methane dimensions unspecified is approximately 30 times the warming effect of one ton of carbon on a 100-year scale (i.e., methane has a global warming potential of 29.8±11). Most of the methane released to the atmosphere during this period of time would have been from wetlands, swamps, and forests. The atmospheric methane concentration today is 0.000179% or 1.79 ppmv. As a result of the warmer climate and the sea level rise associated with the early Eocene, more wetlands, more forests, and more coal deposits would have been available for methane release. If we compare the early Eocene production of methane to current levels of atmospheric methane, the early Eocene would have produced triple the amount of methane. The warm temperatures during the early Eocene could have increased methane production rates, and methane that is released into the atmosphere would in turn warm the troposphere, cool the stratosphere, and produce water vapor and carbon dioxide through oxidation. Biogenic production of methane produces carbon dioxide and water vapor along with the methane, as well as yielding infrared radiation. The breakdown of methane in an atmosphere containing oxygen produces carbon monoxide, water vapor and infrared radiation. The carbon monoxide is not stable, so it eventually becomes carbon dioxide and in doing so releases yet more infrared radiation. Water vapor traps more infrared than does carbon dioxide. Hyperthermals through the early Eocene During the warming in the early Eocene between 55 and 52 Ma, there were a series of short-term changes of carbon isotope composition in the ocean. These isotope changes occurred due to the release of carbon from the ocean into the atmosphere that led to a temperature increase of 4–8 °C (7.2–14.4 °F) at the surface of the ocean. These hyperthermals led to increased perturbations in planktonic and benthic foraminifera, with a higher rate of sedimentation as a consequence of the warmer temperatures. Recent analysis of and research into these hyperthermals in the early Eocene has led to hypotheses that the hyperthermals are based on orbital parameters, in particular eccentricity and obliquity. The hyperthermals in the early Eocene, notably the Palaeocene–Eocene Thermal Maximum (PETM), the Eocene Thermal Maximum 2 (ETM2), and the Eocene Thermal Maximum 3 (ETM3), were analyzed and found that orbital control may have had a role in triggering the ETM2 and ETM3. Equable climate problem One of the unique features of the Eocene's climate as mentioned before was the equable and homogeneous climate that existed in the early parts of the Eocene. A multitude of proxies support the presence of a warmer equable climate being present during this period of time. A few of these proxies include the presence of fossils native to warm climates, such as crocodiles, located in the higher latitudes, the presence in the high latitudes of frost-intolerant flora such as palm trees which cannot survive during sustained freezes, and fossils of snakes found in the tropics that would require much higher average temperatures to sustain them. TEX86 BAYSPAR measurements indicate extremely high sea surface temperatures of 40 °C (104 °F) to 45 °C (113 °F) at low latitudes, although clumped isotope analyses point to a maximum low latitude sea surface temperature of 36.3 °C (97.3 °F) ± 1.9 °C (35.4 °F) during the Early Eocene Climatic Optimum. Relative to present-day values, bottom water temperatures are 10 °C (18 °F) higher according to isotope proxies. With these bottom water temperatures, temperatures in areas where deep water forms near the poles are unable to be much cooler than the bottom water temperatures.An issue arises, however, when trying to model the Eocene and reproduce the results that are found with the proxy data. Using all different ranges of greenhouse gasses that occurred during the early Eocene, models were unable to produce the warming that was found at the poles and the reduced seasonality that occurs with winters at the poles being substantially warmer. The models, while accurately predicting the tropics, tend to produce significantly cooler temperatures of up to 20 °C (36 °F) colder than the actual determined temperature at the poles. This error has been classified as the "equable climate problem". To solve this problem, the solution would involve finding a process to warm the poles without warming the tropics. Some hypotheses and tests which attempt to find the process are listed below. Large lakes Due to the nature of water as opposed to land, less temperature variability would be present if a large body of water is also present. In an attempt to try to mitigate the cooling polar temperatures, large lakes were proposed to mitigate seasonal climate changes. To replicate this case, a lake was inserted into North America and a climate model was run using varying carbon dioxide levels. The model runs concluded that while the lake did reduce the seasonality of the region greater than just an increase in carbon dioxide, the addition of a large lake was unable to reduce the seasonality to the levels shown by the floral and faunal data. Ocean heat transport The transport of heat from the tropics to the poles, much like how ocean heat transport functions in modern times, was considered a possibility for the increased temperature and reduced seasonality for the poles. With the increased sea surface temperatures and the increased temperature of the deep ocean water during the early Eocene, one common hypothesis was that due to these increases there would be a greater transport of heat from the tropics to the poles. Simulating these differences, the models produced lower heat transport due to the lower temperature gradients and were unsuccessful in producing an equable climate from only ocean heat transport. Orbital parameters While typically seen as a control on ice growth and seasonality, the orbital parameters were theorized as a possible control on continental temperatures and seasonality. Simulating the Eocene by using an ice free planet, eccentricity, obliquity, and precession were modified in different model runs to determine all the possible different scenarios that could occur and their effects on temperature. One particular case led to warmer winters and cooler summer by up to 30% in the North American continent, and it reduced the seasonal variation of temperature by up to 75%. While orbital parameters did not produce the warming at the poles, the parameters did show a great effect on seasonality and needed to be considered. Polar stratospheric clouds Another method considered for producing the warm polar temperatures were polar stratospheric clouds. Polar stratospheric clouds are clouds that occur in the lower stratosphere at very low temperatures. Polar stratospheric clouds have a great impact on radiative forcing. Due to their minimal albedo properties and their optical thickness, polar stratospheric clouds act similar to a greenhouse gas and traps outgoing longwave radiation. Different types of polar stratospheric clouds occur in the atmosphere: polar stratospheric clouds that are created due to interactions with nitric or sulfuric acid and water (Type I) or polar stratospheric clouds that are created with only water ice (Type II).Methane is an important factor in the creation of the primary Type II polar stratospheric clouds that were created in the early Eocene. Since water vapor is the only supporting substance used in Type II polar stratospheric clouds, the presence of water vapor in the lower stratosphere is necessary where in most situations the presence of water vapor in the lower stratosphere is rare. When methane is oxidized, a significant amount of water vapor is released. Another requirement for polar stratospheric clouds is cold temperatures to ensure condensation and cloud production. Polar stratospheric cloud production, since it requires the cold temperatures, is usually limited to nighttime and winter conditions. With this combination of wetter and colder conditions in the lower stratosphere, polar stratospheric clouds could have formed over wide areas in Polar Regions.To test the polar stratospheric clouds effects on the Eocene climate, models were run comparing the effects of polar stratospheric clouds at the poles to an increase in atmospheric carbon dioxide. The polar stratospheric clouds had a warming effect on the poles, increasing temperatures by up to 20 °C in the winter months. A multitude of feedbacks also occurred in the models due to the polar stratospheric clouds' presence. Any ice growth was slowed immensely and would lead to any present ice melting. Only the poles were affected with the change in temperature and the tropics were unaffected, which with an increase in atmospheric carbon dioxide would also cause the tropics to increase in temperature. Due to the warming of the troposphere from the increased greenhouse effect of the polar stratospheric clouds, the stratosphere would cool and would potentially increase the amount of polar stratospheric clouds. While the polar stratospheric clouds could explain the reduction of the equator to pole temperature gradient and the increased temperatures at the poles during the early Eocene, there are a few drawbacks to maintaining polar stratospheric clouds for an extended period of time. Separate model runs were used to determine the sustainability of the polar stratospheric clouds. It was determined that in order to maintain the lower stratospheric water vapor, methane would need to be continually released and sustained. In addition, the amounts of ice and condensation nuclei would need to be high in order for the polar stratospheric cloud to sustain itself and eventually expand. Middle Eocene The Eocene is not only known for containing the warmest period during the Cenozoic; it also marked the decline into an icehouse climate and the rapid expansion of the Antarctic ice sheet. The transition from a warming climate into a cooling climate began at around 49 Ma. Isotopes of carbon and oxygen indicate a shift to a global cooling climate. The cause of the cooling has been attributed to a significant decrease of >2,000 ppm in atmospheric carbon dioxide concentrations. One proposed cause of the reduction in carbon dioxide during the warming to cooling transition was the azolla event. With the equable climate during the early Eocene, warm temperatures in the arctic allowed for the growth of azolla, which is a floating aquatic fern, on the Arctic Ocean. The significantly high amounts of carbon dioxide also acted to facilitate azolla blooms across the Arctic Ocean. Compared to current carbon dioxide levels, these azolla grew rapidly in the enhanced carbon dioxide levels found in the early Eocene. The isolation of the Arctic Ocean, evidenced by euxinia that occurred at this time, led to stagnant waters and as the azolla sank to the sea floor, they became part of the sediments on the seabed and effectively sequestered the carbon by locking it out of the atmosphere for good. The ability for the azolla to sequester carbon is exceptional, and the enhanced burial of azolla could have had a significant effect on the world atmospheric carbon content and may have been the event to begin the transition into an ice house climate. The azolla event could have led to a draw down of atmospheric carbon dioxide of up to 470 ppm. Assuming the carbon dioxide concentrations were at 900 ppmv prior to the Azolla Event they would have dropped to 430 ppmv, or 30 ppmv more than they are today, after the Azolla Event. This cooling trend at the end of the Early Eocene Climatic Optimum has also been proposed to have been caused by increased siliceous plankton productivity and marine carbon burial, which also helped draw carbon dioxide out of the atmosphere. Cooling after this event continued due to continual decrease in atmospheric carbon dioxide from organic productivity and weathering from mountain building.Global cooling continued until there was a major reversal from cooling to warming in the Bartonian. This warming event, signifying a sudden and temporary reversal of the cooling conditions, is known as the Middle Eocene Climatic Optimum (MECO). At around 41.5 Ma, stable isotopic analysis of samples from Southern Ocean drilling sites indicated a warming event for 600,000 years. A similar shift in carbon isotopes is known from the Northern Hemisphere in the Scaglia Limestones of Italy. Oxygen isotope analysis showed a large negative change in the proportion of heavier oxygen isotopes to lighter oxygen isotopes, which indicates an increase in global temperatures. The warming is considered to be primarily due to carbon dioxide increases, because carbon isotope signatures rule out major methane release during this short-term warming. A sharp increase in atmospheric carbon dioxide was observed with a maximum of 4,000 ppm: the highest amount of atmospheric carbon dioxide detected during the Eocene. Other studies suggest a more modest rise in carbon dioxide levels. The increase in atmospheric carbon dioxide has also been hypothesised to have been driven by increased seafloor spreading rates and metamorphic decarbonation reactions between Australia and Antarctica and increased amounts of volcanism in the region. One possible cause of atmospheric carbon dioxide increase could have been a sudden increase due to metamorphic release due to continental drift and collision of India with Asia and the resulting formation of the Himalayas; however, data on the exact timing of metamorphic release of atmospheric carbon dioxide is not well resolved in the data. Recent studies have mentioned, however, that the removal of the ocean between Asia and India could have released significant amounts of carbon dioxide. Another hypothesis still implicates a diminished negative feedback of silicate weathering as a result of continental rocks having become less weatherable during the warm Early and Middle Eocene, allowing volcanically released carbon dioxide to persist in the atmosphere for longer. Yet another explanation hypothesises that MECO warming was caused by the simultaneous occurrence of minima in both the 400 kyr and 2.4 Myr eccentricity cycles. During the MECO, sea surface temperatures in the Tethys Ocean jumped to 32-36 °C, and Tethyan seawater became more dysoxic. A decline in carbonate accumulation at ocean depths of greater than three kilometres took place synchronously with the peak of the MECO, signifying ocean acidification took place in the deep ocean. An abrupt decrease in lakewater salinity in western North America occurred during this warming interval. This warming is short lived, as benthic oxygen isotope records indicate a return to cooling at ~40 Ma. Late Eocene At the end of the Middle Eocene Climatic Optimum, cooling and the carbon dioxide drawdown continued through the late Eocene and into the Eocene–Oligocene transition around 34 Ma. The post-MECO cooling brought with it a major aridification trend in Asia. The cooling during the initial stages of the opening of the Drake Passage ~38.5 Ma was not global, as evidenced by an absence of cooling in the North Atlantic. During the cooling period, benthic oxygen isotopes show the possibility of ice creation and ice increase during this later cooling. The end of the Eocene and beginning of the Oligocene is marked with the massive expansion of area of the Antarctic ice sheet that was a major step into the icehouse climate. Multiple proxies, such as oxygen isotopes and alkenones, indicate that at the Eocene–Oligocene transition, the atmospheric carbon dioxide concentration had decreased to around 750–800 ppm, approximately twice that of present levels. Along with the decrease of atmospheric carbon dioxide reducing the global temperature, orbital factors in ice creation can be seen with 100,000-year and 400,000-year fluctuations in benthic oxygen isotope records. Another major contribution to the expansion of the ice sheet was the creation of the Antarctic Circumpolar Current. The creation of the Antarctic circumpolar current would isolate the cold water around the Antarctic, which would reduce heat transport to the Antarctic along with creating ocean gyres that result in the upwelling of colder bottom waters. The issue with this hypothesis of the consideration of this being a factor for the Eocene-Oligocene transition is the timing of the creation of the circulation is uncertain. For Drake Passage, sediments indicate the opening occurred ~41 Ma while tectonics indicate that this occurred ~32 Ma. Flora During the early-middle Eocene, forests covered most of the Earth including the poles. Tropical forests extended across much of modern Africa, South America, Central America, India, South-east Asia and China. Paratropical forests grew over North America, Europe and Russia, with broad-leafed evergreen and broad-leafed deciduous forests at higher latitudes.Polar forests were quite extensive. Fossils and even preserved remains of trees such as swamp cypress and dawn redwood from the Eocene have been found on Ellesmere Island in the Arctic. Even at that time, Ellesmere Island was only a few degrees in latitude further south than it is today. Fossils of subtropical and even tropical trees and plants from the Eocene also have been found in Greenland and Alaska. Tropical rainforests grew as far north as northern North America and Europe.Palm trees were growing as far north as Alaska and northern Europe during the early Eocene, although they became less abundant as the climate cooled. Dawn redwoods were far more extensive as well.The earliest definitive Eucalyptus fossils were dated from 51.9 Mya, and were found in the Laguna del Hunco deposit in Chubut province in Argentina.Cooling began mid-period, and by the end of the Eocene continental interiors had begun to dry, with forests thinning considerably in some areas. The newly evolved grasses were still confined to river banks and lake shores, and had not yet expanded into plains and savannas.The cooling also brought seasonal changes. Deciduous trees, better able to cope with large temperature changes, began to overtake evergreen tropical species. By the end of the period, deciduous forests covered large parts of the northern continents, including North America, Eurasia and the Arctic, and rainforests held on only in equatorial South America, Africa, India and Australia.Antarctica began the Eocene fringed with a warm temperate to sub-tropical rainforest. Pollen found in Prydz Bay from the Eocene suggest taiga forest existed there. It became much colder as the period progressed; the heat-loving tropical flora was wiped out, and by the beginning of the Oligocene, the continent hosted deciduous forests and vast stretches of tundra. Fauna During the Eocene, plants and marine faunas became quite modern. Many modern bird orders first appeared in the Eocene. The Eocene oceans were warm and teeming with fish and other sea life. Mammals The oldest known fossils of most of the modern mammal orders appear within a brief period during the early Eocene. At the beginning of the Eocene, several new mammal groups arrived in North America. These modern mammals, like artiodactyls, perissodactyls, and primates, had features like long, thin legs, feet, and hands capable of grasping, as well as differentiated teeth adapted for chewing. Dwarf forms reigned. All the members of the new mammal orders were small, under 10 kg; based on comparisons of tooth size, Eocene mammals were only 60% of the size of the primitive Palaeocene mammals that preceded them. They were also smaller than the mammals that followed them. It is assumed that the hot Eocene temperatures favored smaller animals that were better able to manage the heat.Both groups of modern ungulates (hoofed animals) became prevalent because of a major radiation between Europe and North America, along with carnivorous ungulates like Mesonyx. Early forms of many other modern mammalian orders appeared, including horses (most notably the Eohippus), bats, proboscidians (elephants), primates, rodents, and marsupials. Older primitive forms of mammals declined in variety and importance. Important Eocene land fauna fossil remains have been found in western North America, Europe, Patagonia, Egypt, and southeast Asia. Marine fauna are best known from South Asia and the southeast United States.Established megafauna of the Eocene include the Uintatherium, Arsinoitherium, and brontotheres, in which the former two, unlike the latter, did not belong to ungulates but groups that became extinct shortly after their establishments. Large terrestrial mammalian predators began to take form as the terrestrial carnivores like the Hyaenodon and Daphoenus (the earliest lineage of a once-successful predatory family known as bear dogs). Entelodonts meanwhile established themselves as some of the largest omnivores. The first nimravids, including Dinictis, established themselves as amongst the first feliforms to appear. Their groups became highly successful and continued to live past the Eocene. Basilosaurus is a very well-known Eocene whale, but whales as a group had become very diverse during the Eocene, which is when the major transitions from being terrestrial to fully aquatic in cetaceans occurred. The first sirenians were evolving at this time, and would eventually evolve into the extant manatees and dugongs. It is thought that millions of years after the Cretaceous-Paleogene extinction event, brain sizes of mammals now started to increase, "likely driven by a need for greater cognition in increasingly complex environments". Birds Eocene birds include some enigmatic groups with resemblances to modern forms, some of which continued from the Paleocene. Bird taxa of the Eocene include carnivorous psittaciforms, such as Messelasturidae, Halcyornithidae, large flightless forms such as Gastornis and Eleutherornis, long legged falcon Masillaraptor, ancient galliforms such as Gallinuloides, putative rail relatives of the family Songziidae, various pseudotooth birds such as Gigantornis, the ibis relative Rhynchaeites, primitive swifts of the genus Aegialornis, and primitive penguins such as Archaeospheniscus and Inkayacu. Reptiles Reptile fossils from this time, such as fossils of pythons and turtles, are abundant. Insects and arachnids Several rich fossil insect faunas are known from the Eocene, notably the Baltic amber found mainly along the south coast of the Baltic Sea, amber from the Paris Basin, France, the Fur Formation, Denmark, and the Bembridge Marls from the Isle of Wight, England. Insects found in Eocene deposits mostly belong to genera that exist today, though their range has often shifted since the Eocene. For instance the bibionid genus Plecia is common in fossil faunas from presently temperate areas, but only lives in the tropics and subtropics today. Gallery See also Bolca in Italy List of fossil sites (with link directory) London Clay Messel pit in Germany Wadi El Hitan in Egypt Notes References Further reading Ogg, Jim; June, 2004, Overview of Global Boundary Stratotype Sections and Points (GSSP's) Global Stratotype Sections and Points Accessed April 30, 2006. Stanley, Steven M. Earth System History. New York: W.H. Freeman and Company, 1999. ISBN 0-7167-2882-6 External links PaleoMap Project Paleos Eocene page PBS Deep Time: Eocene Eocene and Oligocene Fossils The UPenn Fossil Forest Project, focusing on the Eocene polar forests in Ellesmere Island, Canada Basilosaurus Primitive Eocene Whales Basilosaurus - The plesiosaur that wasn't.... Detailed maps of Tertiary Western North America Map of Eocene Earth Eocene Microfossils: 60+ images of Foraminifera Eocene Epoch. (2011). In Encyclopædia Britannica. Retrieved from Eocene Epoch \| geochronology	part of	{ "answer_start": [ 153 ], "text": [ "Paleogene" ] }
The Eocene (IPA: EE-ə-seen, EE-oh-) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name Eocene comes from the Ancient Greek ἠώς (ēṓs, "dawn") and καινός (kainós, "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the Grande Coupure (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the epoch are well identified, though their exact dates are slightly uncertain. Etymology The term "Eocene" is derived from Ancient Greek ἠώς eos meaning "dawn", and καινός kainos meaning "new" or "recent", as the epoch saw the dawn of recent, or modern, life. Scottish geologist Charles Lyell (ignoring the Quaternary) had divided the Tertiary Epoch into the Eocene, Miocene, Pliocene, and New Pliocene (Holocene) Periods in 1833. British geologist John Phillips had proposed the Cenozoic in 1840 in place of the Tertiary, and Austrian paleontologist Moritz Hörnes had introduced the Paleogene for the Eocene and Neogene for the Miocene and Pliocene in 1853. After decades of inconsistent usage, the newly formed International Commission on Stratigraphy (ICS), in 1969, standardized stratigraphy based on the prevailing opinions in Europe: the Cenozoic Era subdivided into the Tertiary and Quaternary sub-eras, and the Tertiary subdivided into the Paleogene and Neogene periods. In 1978, the Paleogene was officially defined as the Paleocene, Eocene, and Oligocene epochs; and the Neogene as the Miocene and Pliocene epochs. In 1989, Tertiary and Quaternary were removed from the time scale due to the arbitrary nature of their boundary, but Quaternary was reinstated in 2009. Geology Boundaries The beginning of the Eocene is marked by the Paleocene–Eocene Thermal Maximum, a short period of intense warming and ocean acidification brought about by the release of carbon en masse into the atmosphere and ocean systems, which led to a mass extinction of 30–50% of benthic foraminifera–single-celled species which are used as bioindicators of the health of a marine ecosystem—one of the largest in the Cenozoic. This event happened around 55.8 mya, and was one of the most significant periods of global change during the Cenozoic.The end of the Eocene was marked by the Eocene–Oligocene extinction event, also known as the Grande Coupure. Stratigraphy The Eocene is conventionally divided into early (56–47.8 Ma), middle (47.8–38 Ma), and late (38–33.9 Ma) subdivisions. The corresponding rocks are referred to as lower, middle, and upper Eocene. The Ypresian Stage constitutes the lower, the Priabonian Stage the upper; and the Lutetian and Bartonian stages are united as the middle Eocene. Palaeogeography and tectonics During the Eocene, the continents continued to drift toward their present positions. At the beginning of the period, Australia and Antarctica remained connected, and warm equatorial currents may have mixed with colder Antarctic waters, distributing the heat around the planet and keeping global temperatures high. When Australia split from the southern continent around 45 Ma, the warm equatorial currents were routed away from Antarctica. An isolated cold water channel developed between the two continents. However, modeling results call into question the thermal isolation model for late Eocene cooling, and decreasing carbon dioxide levels in the atmosphere may have been more important. Once the Antarctic region began to cool down, the ocean surrounding Antarctica began to freeze, sending cold water and icefloes north and reinforcing the cooling.The northern supercontinent of Laurasia began to fragment, as Europe, Greenland and North America drifted apart.In western North America, the Laramide Orogeny came to an end in the Eocene, and compression was replaced with crustal extension that ultimately gave rise to the Basin and Range Province. Huge lakes formed in the high flat basins among uplifts, resulting in the deposition of the Green River Formation lagerstätte.At about 35 Ma, an asteroid impact on the eastern coast of North America formed the Chesapeake Bay impact crater.In Europe, the Tethys Sea finally disappeared, while the uplift of the Alps isolated its final remnant, the Mediterranean, and created another shallow sea with island archipelagos to the north. Though the North Atlantic was opening, a land connection appears to have remained between North America and Europe since the faunas of the two regions are very similar.Eurasia was separated in three different landmasses 50 Ma; Western Europe, Balkanatolia and Asia. About 40 Ma, Balkanatolia and Asia were connected, while Europe was connected 34 Ma.India collided with Asia, folding to initiate formation of the Himalayas. India collided with the Kohistan–Ladakh Arc around 50.2 Ma and with Karakoram around 40.4 Ma, with the final collision between Asia and India occurring ~40 Ma. Climate The Eocene Epoch contained a wide variety of different climate conditions that includes the warmest climate in the Cenozoic Era, and arguably the warmest time interval since the Permian-Triassic mass extinction and Early Triassic, and ends in an icehouse climate. The evolution of the Eocene climate began with warming after the end of the Paleocene–Eocene Thermal Maximum (PETM) at 56 Ma to a maximum during the Eocene Optimum at around 49 Ma. Recent study show elevation-dependent temperature changes during the Eocene hothouse. During this period of time, little to no ice was present on Earth with a smaller difference in temperature from the equator to the poles. Because of this the maximum sea level was 150 meters higher than current levels. Following the maximum was a descent into an icehouse climate from the Eocene Optimum to the Eocene-Oligocene transition at 34 Ma. During this decrease, ice began to reappear at the poles, and the Eocene-Oligocene transition is the period of time where the Antarctic ice sheet began to rapidly expand. Early Eocene Greenhouse gases, in particular carbon dioxide and methane, played a significant role during the Eocene in controlling the surface temperature. The end of the PETM was met with very large sequestration of carbon dioxide into the forms of methane clathrate, coal, and crude oil at the bottom of the Arctic Ocean, that reduced the atmospheric carbon dioxide. This event was similar in magnitude to the massive release of greenhouse gasses at the beginning of the PETM, and it is hypothesized that the sequestration was mainly due to organic carbon burial and weathering of silicates. For the early Eocene there is much discussion on how much carbon dioxide was in the atmosphere. This is due to numerous proxies representing different atmospheric carbon dioxide content. For example, diverse geochemical and paleontological proxies indicate that at the maximum of global warmth the atmospheric carbon dioxide values were at 700–900 ppm while other proxies such as pedogenic (soil building) carbonate and marine boron isotopes indicate large changes of carbon dioxide of over 2,000 ppm over periods of time of less than 1 million years. Sources for this large influx of carbon dioxide could be attributed to volcanic out-gassing due to North Atlantic rifting or oxidation of methane stored in large reservoirs deposited from the PETM event in the sea floor or wetland environments. For contrast, today the carbon dioxide levels are at 400 ppm or 0.04%. At about the beginning of the Eocene Epoch (55.8–33.9 Ma) the amount of oxygen in the earth's atmosphere more or less doubled.During the early Eocene, methane was another greenhouse gas that had a drastic effect on the climate. The warming effect of one ton of methane dimensions unspecified is approximately 30 times the warming effect of one ton of carbon on a 100-year scale (i.e., methane has a global warming potential of 29.8±11). Most of the methane released to the atmosphere during this period of time would have been from wetlands, swamps, and forests. The atmospheric methane concentration today is 0.000179% or 1.79 ppmv. As a result of the warmer climate and the sea level rise associated with the early Eocene, more wetlands, more forests, and more coal deposits would have been available for methane release. If we compare the early Eocene production of methane to current levels of atmospheric methane, the early Eocene would have produced triple the amount of methane. The warm temperatures during the early Eocene could have increased methane production rates, and methane that is released into the atmosphere would in turn warm the troposphere, cool the stratosphere, and produce water vapor and carbon dioxide through oxidation. Biogenic production of methane produces carbon dioxide and water vapor along with the methane, as well as yielding infrared radiation. The breakdown of methane in an atmosphere containing oxygen produces carbon monoxide, water vapor and infrared radiation. The carbon monoxide is not stable, so it eventually becomes carbon dioxide and in doing so releases yet more infrared radiation. Water vapor traps more infrared than does carbon dioxide. Hyperthermals through the early Eocene During the warming in the early Eocene between 55 and 52 Ma, there were a series of short-term changes of carbon isotope composition in the ocean. These isotope changes occurred due to the release of carbon from the ocean into the atmosphere that led to a temperature increase of 4–8 °C (7.2–14.4 °F) at the surface of the ocean. These hyperthermals led to increased perturbations in planktonic and benthic foraminifera, with a higher rate of sedimentation as a consequence of the warmer temperatures. Recent analysis of and research into these hyperthermals in the early Eocene has led to hypotheses that the hyperthermals are based on orbital parameters, in particular eccentricity and obliquity. The hyperthermals in the early Eocene, notably the Palaeocene–Eocene Thermal Maximum (PETM), the Eocene Thermal Maximum 2 (ETM2), and the Eocene Thermal Maximum 3 (ETM3), were analyzed and found that orbital control may have had a role in triggering the ETM2 and ETM3. Equable climate problem One of the unique features of the Eocene's climate as mentioned before was the equable and homogeneous climate that existed in the early parts of the Eocene. A multitude of proxies support the presence of a warmer equable climate being present during this period of time. A few of these proxies include the presence of fossils native to warm climates, such as crocodiles, located in the higher latitudes, the presence in the high latitudes of frost-intolerant flora such as palm trees which cannot survive during sustained freezes, and fossils of snakes found in the tropics that would require much higher average temperatures to sustain them. TEX86 BAYSPAR measurements indicate extremely high sea surface temperatures of 40 °C (104 °F) to 45 °C (113 °F) at low latitudes, although clumped isotope analyses point to a maximum low latitude sea surface temperature of 36.3 °C (97.3 °F) ± 1.9 °C (35.4 °F) during the Early Eocene Climatic Optimum. Relative to present-day values, bottom water temperatures are 10 °C (18 °F) higher according to isotope proxies. With these bottom water temperatures, temperatures in areas where deep water forms near the poles are unable to be much cooler than the bottom water temperatures.An issue arises, however, when trying to model the Eocene and reproduce the results that are found with the proxy data. Using all different ranges of greenhouse gasses that occurred during the early Eocene, models were unable to produce the warming that was found at the poles and the reduced seasonality that occurs with winters at the poles being substantially warmer. The models, while accurately predicting the tropics, tend to produce significantly cooler temperatures of up to 20 °C (36 °F) colder than the actual determined temperature at the poles. This error has been classified as the "equable climate problem". To solve this problem, the solution would involve finding a process to warm the poles without warming the tropics. Some hypotheses and tests which attempt to find the process are listed below. Large lakes Due to the nature of water as opposed to land, less temperature variability would be present if a large body of water is also present. In an attempt to try to mitigate the cooling polar temperatures, large lakes were proposed to mitigate seasonal climate changes. To replicate this case, a lake was inserted into North America and a climate model was run using varying carbon dioxide levels. The model runs concluded that while the lake did reduce the seasonality of the region greater than just an increase in carbon dioxide, the addition of a large lake was unable to reduce the seasonality to the levels shown by the floral and faunal data. Ocean heat transport The transport of heat from the tropics to the poles, much like how ocean heat transport functions in modern times, was considered a possibility for the increased temperature and reduced seasonality for the poles. With the increased sea surface temperatures and the increased temperature of the deep ocean water during the early Eocene, one common hypothesis was that due to these increases there would be a greater transport of heat from the tropics to the poles. Simulating these differences, the models produced lower heat transport due to the lower temperature gradients and were unsuccessful in producing an equable climate from only ocean heat transport. Orbital parameters While typically seen as a control on ice growth and seasonality, the orbital parameters were theorized as a possible control on continental temperatures and seasonality. Simulating the Eocene by using an ice free planet, eccentricity, obliquity, and precession were modified in different model runs to determine all the possible different scenarios that could occur and their effects on temperature. One particular case led to warmer winters and cooler summer by up to 30% in the North American continent, and it reduced the seasonal variation of temperature by up to 75%. While orbital parameters did not produce the warming at the poles, the parameters did show a great effect on seasonality and needed to be considered. Polar stratospheric clouds Another method considered for producing the warm polar temperatures were polar stratospheric clouds. Polar stratospheric clouds are clouds that occur in the lower stratosphere at very low temperatures. Polar stratospheric clouds have a great impact on radiative forcing. Due to their minimal albedo properties and their optical thickness, polar stratospheric clouds act similar to a greenhouse gas and traps outgoing longwave radiation. Different types of polar stratospheric clouds occur in the atmosphere: polar stratospheric clouds that are created due to interactions with nitric or sulfuric acid and water (Type I) or polar stratospheric clouds that are created with only water ice (Type II).Methane is an important factor in the creation of the primary Type II polar stratospheric clouds that were created in the early Eocene. Since water vapor is the only supporting substance used in Type II polar stratospheric clouds, the presence of water vapor in the lower stratosphere is necessary where in most situations the presence of water vapor in the lower stratosphere is rare. When methane is oxidized, a significant amount of water vapor is released. Another requirement for polar stratospheric clouds is cold temperatures to ensure condensation and cloud production. Polar stratospheric cloud production, since it requires the cold temperatures, is usually limited to nighttime and winter conditions. With this combination of wetter and colder conditions in the lower stratosphere, polar stratospheric clouds could have formed over wide areas in Polar Regions.To test the polar stratospheric clouds effects on the Eocene climate, models were run comparing the effects of polar stratospheric clouds at the poles to an increase in atmospheric carbon dioxide. The polar stratospheric clouds had a warming effect on the poles, increasing temperatures by up to 20 °C in the winter months. A multitude of feedbacks also occurred in the models due to the polar stratospheric clouds' presence. Any ice growth was slowed immensely and would lead to any present ice melting. Only the poles were affected with the change in temperature and the tropics were unaffected, which with an increase in atmospheric carbon dioxide would also cause the tropics to increase in temperature. Due to the warming of the troposphere from the increased greenhouse effect of the polar stratospheric clouds, the stratosphere would cool and would potentially increase the amount of polar stratospheric clouds. While the polar stratospheric clouds could explain the reduction of the equator to pole temperature gradient and the increased temperatures at the poles during the early Eocene, there are a few drawbacks to maintaining polar stratospheric clouds for an extended period of time. Separate model runs were used to determine the sustainability of the polar stratospheric clouds. It was determined that in order to maintain the lower stratospheric water vapor, methane would need to be continually released and sustained. In addition, the amounts of ice and condensation nuclei would need to be high in order for the polar stratospheric cloud to sustain itself and eventually expand. Middle Eocene The Eocene is not only known for containing the warmest period during the Cenozoic; it also marked the decline into an icehouse climate and the rapid expansion of the Antarctic ice sheet. The transition from a warming climate into a cooling climate began at around 49 Ma. Isotopes of carbon and oxygen indicate a shift to a global cooling climate. The cause of the cooling has been attributed to a significant decrease of >2,000 ppm in atmospheric carbon dioxide concentrations. One proposed cause of the reduction in carbon dioxide during the warming to cooling transition was the azolla event. With the equable climate during the early Eocene, warm temperatures in the arctic allowed for the growth of azolla, which is a floating aquatic fern, on the Arctic Ocean. The significantly high amounts of carbon dioxide also acted to facilitate azolla blooms across the Arctic Ocean. Compared to current carbon dioxide levels, these azolla grew rapidly in the enhanced carbon dioxide levels found in the early Eocene. The isolation of the Arctic Ocean, evidenced by euxinia that occurred at this time, led to stagnant waters and as the azolla sank to the sea floor, they became part of the sediments on the seabed and effectively sequestered the carbon by locking it out of the atmosphere for good. The ability for the azolla to sequester carbon is exceptional, and the enhanced burial of azolla could have had a significant effect on the world atmospheric carbon content and may have been the event to begin the transition into an ice house climate. The azolla event could have led to a draw down of atmospheric carbon dioxide of up to 470 ppm. Assuming the carbon dioxide concentrations were at 900 ppmv prior to the Azolla Event they would have dropped to 430 ppmv, or 30 ppmv more than they are today, after the Azolla Event. This cooling trend at the end of the Early Eocene Climatic Optimum has also been proposed to have been caused by increased siliceous plankton productivity and marine carbon burial, which also helped draw carbon dioxide out of the atmosphere. Cooling after this event continued due to continual decrease in atmospheric carbon dioxide from organic productivity and weathering from mountain building.Global cooling continued until there was a major reversal from cooling to warming in the Bartonian. This warming event, signifying a sudden and temporary reversal of the cooling conditions, is known as the Middle Eocene Climatic Optimum (MECO). At around 41.5 Ma, stable isotopic analysis of samples from Southern Ocean drilling sites indicated a warming event for 600,000 years. A similar shift in carbon isotopes is known from the Northern Hemisphere in the Scaglia Limestones of Italy. Oxygen isotope analysis showed a large negative change in the proportion of heavier oxygen isotopes to lighter oxygen isotopes, which indicates an increase in global temperatures. The warming is considered to be primarily due to carbon dioxide increases, because carbon isotope signatures rule out major methane release during this short-term warming. A sharp increase in atmospheric carbon dioxide was observed with a maximum of 4,000 ppm: the highest amount of atmospheric carbon dioxide detected during the Eocene. Other studies suggest a more modest rise in carbon dioxide levels. The increase in atmospheric carbon dioxide has also been hypothesised to have been driven by increased seafloor spreading rates and metamorphic decarbonation reactions between Australia and Antarctica and increased amounts of volcanism in the region. One possible cause of atmospheric carbon dioxide increase could have been a sudden increase due to metamorphic release due to continental drift and collision of India with Asia and the resulting formation of the Himalayas; however, data on the exact timing of metamorphic release of atmospheric carbon dioxide is not well resolved in the data. Recent studies have mentioned, however, that the removal of the ocean between Asia and India could have released significant amounts of carbon dioxide. Another hypothesis still implicates a diminished negative feedback of silicate weathering as a result of continental rocks having become less weatherable during the warm Early and Middle Eocene, allowing volcanically released carbon dioxide to persist in the atmosphere for longer. Yet another explanation hypothesises that MECO warming was caused by the simultaneous occurrence of minima in both the 400 kyr and 2.4 Myr eccentricity cycles. During the MECO, sea surface temperatures in the Tethys Ocean jumped to 32-36 °C, and Tethyan seawater became more dysoxic. A decline in carbonate accumulation at ocean depths of greater than three kilometres took place synchronously with the peak of the MECO, signifying ocean acidification took place in the deep ocean. An abrupt decrease in lakewater salinity in western North America occurred during this warming interval. This warming is short lived, as benthic oxygen isotope records indicate a return to cooling at ~40 Ma. Late Eocene At the end of the Middle Eocene Climatic Optimum, cooling and the carbon dioxide drawdown continued through the late Eocene and into the Eocene–Oligocene transition around 34 Ma. The post-MECO cooling brought with it a major aridification trend in Asia. The cooling during the initial stages of the opening of the Drake Passage ~38.5 Ma was not global, as evidenced by an absence of cooling in the North Atlantic. During the cooling period, benthic oxygen isotopes show the possibility of ice creation and ice increase during this later cooling. The end of the Eocene and beginning of the Oligocene is marked with the massive expansion of area of the Antarctic ice sheet that was a major step into the icehouse climate. Multiple proxies, such as oxygen isotopes and alkenones, indicate that at the Eocene–Oligocene transition, the atmospheric carbon dioxide concentration had decreased to around 750–800 ppm, approximately twice that of present levels. Along with the decrease of atmospheric carbon dioxide reducing the global temperature, orbital factors in ice creation can be seen with 100,000-year and 400,000-year fluctuations in benthic oxygen isotope records. Another major contribution to the expansion of the ice sheet was the creation of the Antarctic Circumpolar Current. The creation of the Antarctic circumpolar current would isolate the cold water around the Antarctic, which would reduce heat transport to the Antarctic along with creating ocean gyres that result in the upwelling of colder bottom waters. The issue with this hypothesis of the consideration of this being a factor for the Eocene-Oligocene transition is the timing of the creation of the circulation is uncertain. For Drake Passage, sediments indicate the opening occurred ~41 Ma while tectonics indicate that this occurred ~32 Ma. Flora During the early-middle Eocene, forests covered most of the Earth including the poles. Tropical forests extended across much of modern Africa, South America, Central America, India, South-east Asia and China. Paratropical forests grew over North America, Europe and Russia, with broad-leafed evergreen and broad-leafed deciduous forests at higher latitudes.Polar forests were quite extensive. Fossils and even preserved remains of trees such as swamp cypress and dawn redwood from the Eocene have been found on Ellesmere Island in the Arctic. Even at that time, Ellesmere Island was only a few degrees in latitude further south than it is today. Fossils of subtropical and even tropical trees and plants from the Eocene also have been found in Greenland and Alaska. Tropical rainforests grew as far north as northern North America and Europe.Palm trees were growing as far north as Alaska and northern Europe during the early Eocene, although they became less abundant as the climate cooled. Dawn redwoods were far more extensive as well.The earliest definitive Eucalyptus fossils were dated from 51.9 Mya, and were found in the Laguna del Hunco deposit in Chubut province in Argentina.Cooling began mid-period, and by the end of the Eocene continental interiors had begun to dry, with forests thinning considerably in some areas. The newly evolved grasses were still confined to river banks and lake shores, and had not yet expanded into plains and savannas.The cooling also brought seasonal changes. Deciduous trees, better able to cope with large temperature changes, began to overtake evergreen tropical species. By the end of the period, deciduous forests covered large parts of the northern continents, including North America, Eurasia and the Arctic, and rainforests held on only in equatorial South America, Africa, India and Australia.Antarctica began the Eocene fringed with a warm temperate to sub-tropical rainforest. Pollen found in Prydz Bay from the Eocene suggest taiga forest existed there. It became much colder as the period progressed; the heat-loving tropical flora was wiped out, and by the beginning of the Oligocene, the continent hosted deciduous forests and vast stretches of tundra. Fauna During the Eocene, plants and marine faunas became quite modern. Many modern bird orders first appeared in the Eocene. The Eocene oceans were warm and teeming with fish and other sea life. Mammals The oldest known fossils of most of the modern mammal orders appear within a brief period during the early Eocene. At the beginning of the Eocene, several new mammal groups arrived in North America. These modern mammals, like artiodactyls, perissodactyls, and primates, had features like long, thin legs, feet, and hands capable of grasping, as well as differentiated teeth adapted for chewing. Dwarf forms reigned. All the members of the new mammal orders were small, under 10 kg; based on comparisons of tooth size, Eocene mammals were only 60% of the size of the primitive Palaeocene mammals that preceded them. They were also smaller than the mammals that followed them. It is assumed that the hot Eocene temperatures favored smaller animals that were better able to manage the heat.Both groups of modern ungulates (hoofed animals) became prevalent because of a major radiation between Europe and North America, along with carnivorous ungulates like Mesonyx. Early forms of many other modern mammalian orders appeared, including horses (most notably the Eohippus), bats, proboscidians (elephants), primates, rodents, and marsupials. Older primitive forms of mammals declined in variety and importance. Important Eocene land fauna fossil remains have been found in western North America, Europe, Patagonia, Egypt, and southeast Asia. Marine fauna are best known from South Asia and the southeast United States.Established megafauna of the Eocene include the Uintatherium, Arsinoitherium, and brontotheres, in which the former two, unlike the latter, did not belong to ungulates but groups that became extinct shortly after their establishments. Large terrestrial mammalian predators began to take form as the terrestrial carnivores like the Hyaenodon and Daphoenus (the earliest lineage of a once-successful predatory family known as bear dogs). Entelodonts meanwhile established themselves as some of the largest omnivores. The first nimravids, including Dinictis, established themselves as amongst the first feliforms to appear. Their groups became highly successful and continued to live past the Eocene. Basilosaurus is a very well-known Eocene whale, but whales as a group had become very diverse during the Eocene, which is when the major transitions from being terrestrial to fully aquatic in cetaceans occurred. The first sirenians were evolving at this time, and would eventually evolve into the extant manatees and dugongs. It is thought that millions of years after the Cretaceous-Paleogene extinction event, brain sizes of mammals now started to increase, "likely driven by a need for greater cognition in increasingly complex environments". Birds Eocene birds include some enigmatic groups with resemblances to modern forms, some of which continued from the Paleocene. Bird taxa of the Eocene include carnivorous psittaciforms, such as Messelasturidae, Halcyornithidae, large flightless forms such as Gastornis and Eleutherornis, long legged falcon Masillaraptor, ancient galliforms such as Gallinuloides, putative rail relatives of the family Songziidae, various pseudotooth birds such as Gigantornis, the ibis relative Rhynchaeites, primitive swifts of the genus Aegialornis, and primitive penguins such as Archaeospheniscus and Inkayacu. Reptiles Reptile fossils from this time, such as fossils of pythons and turtles, are abundant. Insects and arachnids Several rich fossil insect faunas are known from the Eocene, notably the Baltic amber found mainly along the south coast of the Baltic Sea, amber from the Paris Basin, France, the Fur Formation, Denmark, and the Bembridge Marls from the Isle of Wight, England. Insects found in Eocene deposits mostly belong to genera that exist today, though their range has often shifted since the Eocene. For instance the bibionid genus Plecia is common in fossil faunas from presently temperate areas, but only lives in the tropics and subtropics today. Gallery See also Bolca in Italy List of fossil sites (with link directory) London Clay Messel pit in Germany Wadi El Hitan in Egypt Notes References Further reading Ogg, Jim; June, 2004, Overview of Global Boundary Stratotype Sections and Points (GSSP's) Global Stratotype Sections and Points Accessed April 30, 2006. Stanley, Steven M. Earth System History. New York: W.H. Freeman and Company, 1999. ISBN 0-7167-2882-6 External links PaleoMap Project Paleos Eocene page PBS Deep Time: Eocene Eocene and Oligocene Fossils The UPenn Fossil Forest Project, focusing on the Eocene polar forests in Ellesmere Island, Canada Basilosaurus Primitive Eocene Whales Basilosaurus - The plesiosaur that wasn't.... Detailed maps of Tertiary Western North America Map of Eocene Earth Eocene Microfossils: 60+ images of Foraminifera Eocene Epoch. (2011). In Encyclopædia Britannica. Retrieved from Eocene Epoch \| geochronology	Commons category	{ "answer_start": [ 4 ], "text": [ "Eocene" ] }
The Eocene (IPA: EE-ə-seen, EE-oh-) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name Eocene comes from the Ancient Greek ἠώς (ēṓs, "dawn") and καινός (kainós, "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the Grande Coupure (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the epoch are well identified, though their exact dates are slightly uncertain. Etymology The term "Eocene" is derived from Ancient Greek ἠώς eos meaning "dawn", and καινός kainos meaning "new" or "recent", as the epoch saw the dawn of recent, or modern, life. Scottish geologist Charles Lyell (ignoring the Quaternary) had divided the Tertiary Epoch into the Eocene, Miocene, Pliocene, and New Pliocene (Holocene) Periods in 1833. British geologist John Phillips had proposed the Cenozoic in 1840 in place of the Tertiary, and Austrian paleontologist Moritz Hörnes had introduced the Paleogene for the Eocene and Neogene for the Miocene and Pliocene in 1853. After decades of inconsistent usage, the newly formed International Commission on Stratigraphy (ICS), in 1969, standardized stratigraphy based on the prevailing opinions in Europe: the Cenozoic Era subdivided into the Tertiary and Quaternary sub-eras, and the Tertiary subdivided into the Paleogene and Neogene periods. In 1978, the Paleogene was officially defined as the Paleocene, Eocene, and Oligocene epochs; and the Neogene as the Miocene and Pliocene epochs. In 1989, Tertiary and Quaternary were removed from the time scale due to the arbitrary nature of their boundary, but Quaternary was reinstated in 2009. Geology Boundaries The beginning of the Eocene is marked by the Paleocene–Eocene Thermal Maximum, a short period of intense warming and ocean acidification brought about by the release of carbon en masse into the atmosphere and ocean systems, which led to a mass extinction of 30–50% of benthic foraminifera–single-celled species which are used as bioindicators of the health of a marine ecosystem—one of the largest in the Cenozoic. This event happened around 55.8 mya, and was one of the most significant periods of global change during the Cenozoic.The end of the Eocene was marked by the Eocene–Oligocene extinction event, also known as the Grande Coupure. Stratigraphy The Eocene is conventionally divided into early (56–47.8 Ma), middle (47.8–38 Ma), and late (38–33.9 Ma) subdivisions. The corresponding rocks are referred to as lower, middle, and upper Eocene. The Ypresian Stage constitutes the lower, the Priabonian Stage the upper; and the Lutetian and Bartonian stages are united as the middle Eocene. Palaeogeography and tectonics During the Eocene, the continents continued to drift toward their present positions. At the beginning of the period, Australia and Antarctica remained connected, and warm equatorial currents may have mixed with colder Antarctic waters, distributing the heat around the planet and keeping global temperatures high. When Australia split from the southern continent around 45 Ma, the warm equatorial currents were routed away from Antarctica. An isolated cold water channel developed between the two continents. However, modeling results call into question the thermal isolation model for late Eocene cooling, and decreasing carbon dioxide levels in the atmosphere may have been more important. Once the Antarctic region began to cool down, the ocean surrounding Antarctica began to freeze, sending cold water and icefloes north and reinforcing the cooling.The northern supercontinent of Laurasia began to fragment, as Europe, Greenland and North America drifted apart.In western North America, the Laramide Orogeny came to an end in the Eocene, and compression was replaced with crustal extension that ultimately gave rise to the Basin and Range Province. Huge lakes formed in the high flat basins among uplifts, resulting in the deposition of the Green River Formation lagerstätte.At about 35 Ma, an asteroid impact on the eastern coast of North America formed the Chesapeake Bay impact crater.In Europe, the Tethys Sea finally disappeared, while the uplift of the Alps isolated its final remnant, the Mediterranean, and created another shallow sea with island archipelagos to the north. Though the North Atlantic was opening, a land connection appears to have remained between North America and Europe since the faunas of the two regions are very similar.Eurasia was separated in three different landmasses 50 Ma; Western Europe, Balkanatolia and Asia. About 40 Ma, Balkanatolia and Asia were connected, while Europe was connected 34 Ma.India collided with Asia, folding to initiate formation of the Himalayas. India collided with the Kohistan–Ladakh Arc around 50.2 Ma and with Karakoram around 40.4 Ma, with the final collision between Asia and India occurring ~40 Ma. Climate The Eocene Epoch contained a wide variety of different climate conditions that includes the warmest climate in the Cenozoic Era, and arguably the warmest time interval since the Permian-Triassic mass extinction and Early Triassic, and ends in an icehouse climate. The evolution of the Eocene climate began with warming after the end of the Paleocene–Eocene Thermal Maximum (PETM) at 56 Ma to a maximum during the Eocene Optimum at around 49 Ma. Recent study show elevation-dependent temperature changes during the Eocene hothouse. During this period of time, little to no ice was present on Earth with a smaller difference in temperature from the equator to the poles. Because of this the maximum sea level was 150 meters higher than current levels. Following the maximum was a descent into an icehouse climate from the Eocene Optimum to the Eocene-Oligocene transition at 34 Ma. During this decrease, ice began to reappear at the poles, and the Eocene-Oligocene transition is the period of time where the Antarctic ice sheet began to rapidly expand. Early Eocene Greenhouse gases, in particular carbon dioxide and methane, played a significant role during the Eocene in controlling the surface temperature. The end of the PETM was met with very large sequestration of carbon dioxide into the forms of methane clathrate, coal, and crude oil at the bottom of the Arctic Ocean, that reduced the atmospheric carbon dioxide. This event was similar in magnitude to the massive release of greenhouse gasses at the beginning of the PETM, and it is hypothesized that the sequestration was mainly due to organic carbon burial and weathering of silicates. For the early Eocene there is much discussion on how much carbon dioxide was in the atmosphere. This is due to numerous proxies representing different atmospheric carbon dioxide content. For example, diverse geochemical and paleontological proxies indicate that at the maximum of global warmth the atmospheric carbon dioxide values were at 700–900 ppm while other proxies such as pedogenic (soil building) carbonate and marine boron isotopes indicate large changes of carbon dioxide of over 2,000 ppm over periods of time of less than 1 million years. Sources for this large influx of carbon dioxide could be attributed to volcanic out-gassing due to North Atlantic rifting or oxidation of methane stored in large reservoirs deposited from the PETM event in the sea floor or wetland environments. For contrast, today the carbon dioxide levels are at 400 ppm or 0.04%. At about the beginning of the Eocene Epoch (55.8–33.9 Ma) the amount of oxygen in the earth's atmosphere more or less doubled.During the early Eocene, methane was another greenhouse gas that had a drastic effect on the climate. The warming effect of one ton of methane dimensions unspecified is approximately 30 times the warming effect of one ton of carbon on a 100-year scale (i.e., methane has a global warming potential of 29.8±11). Most of the methane released to the atmosphere during this period of time would have been from wetlands, swamps, and forests. The atmospheric methane concentration today is 0.000179% or 1.79 ppmv. As a result of the warmer climate and the sea level rise associated with the early Eocene, more wetlands, more forests, and more coal deposits would have been available for methane release. If we compare the early Eocene production of methane to current levels of atmospheric methane, the early Eocene would have produced triple the amount of methane. The warm temperatures during the early Eocene could have increased methane production rates, and methane that is released into the atmosphere would in turn warm the troposphere, cool the stratosphere, and produce water vapor and carbon dioxide through oxidation. Biogenic production of methane produces carbon dioxide and water vapor along with the methane, as well as yielding infrared radiation. The breakdown of methane in an atmosphere containing oxygen produces carbon monoxide, water vapor and infrared radiation. The carbon monoxide is not stable, so it eventually becomes carbon dioxide and in doing so releases yet more infrared radiation. Water vapor traps more infrared than does carbon dioxide. Hyperthermals through the early Eocene During the warming in the early Eocene between 55 and 52 Ma, there were a series of short-term changes of carbon isotope composition in the ocean. These isotope changes occurred due to the release of carbon from the ocean into the atmosphere that led to a temperature increase of 4–8 °C (7.2–14.4 °F) at the surface of the ocean. These hyperthermals led to increased perturbations in planktonic and benthic foraminifera, with a higher rate of sedimentation as a consequence of the warmer temperatures. Recent analysis of and research into these hyperthermals in the early Eocene has led to hypotheses that the hyperthermals are based on orbital parameters, in particular eccentricity and obliquity. The hyperthermals in the early Eocene, notably the Palaeocene–Eocene Thermal Maximum (PETM), the Eocene Thermal Maximum 2 (ETM2), and the Eocene Thermal Maximum 3 (ETM3), were analyzed and found that orbital control may have had a role in triggering the ETM2 and ETM3. Equable climate problem One of the unique features of the Eocene's climate as mentioned before was the equable and homogeneous climate that existed in the early parts of the Eocene. A multitude of proxies support the presence of a warmer equable climate being present during this period of time. A few of these proxies include the presence of fossils native to warm climates, such as crocodiles, located in the higher latitudes, the presence in the high latitudes of frost-intolerant flora such as palm trees which cannot survive during sustained freezes, and fossils of snakes found in the tropics that would require much higher average temperatures to sustain them. TEX86 BAYSPAR measurements indicate extremely high sea surface temperatures of 40 °C (104 °F) to 45 °C (113 °F) at low latitudes, although clumped isotope analyses point to a maximum low latitude sea surface temperature of 36.3 °C (97.3 °F) ± 1.9 °C (35.4 °F) during the Early Eocene Climatic Optimum. Relative to present-day values, bottom water temperatures are 10 °C (18 °F) higher according to isotope proxies. With these bottom water temperatures, temperatures in areas where deep water forms near the poles are unable to be much cooler than the bottom water temperatures.An issue arises, however, when trying to model the Eocene and reproduce the results that are found with the proxy data. Using all different ranges of greenhouse gasses that occurred during the early Eocene, models were unable to produce the warming that was found at the poles and the reduced seasonality that occurs with winters at the poles being substantially warmer. The models, while accurately predicting the tropics, tend to produce significantly cooler temperatures of up to 20 °C (36 °F) colder than the actual determined temperature at the poles. This error has been classified as the "equable climate problem". To solve this problem, the solution would involve finding a process to warm the poles without warming the tropics. Some hypotheses and tests which attempt to find the process are listed below. Large lakes Due to the nature of water as opposed to land, less temperature variability would be present if a large body of water is also present. In an attempt to try to mitigate the cooling polar temperatures, large lakes were proposed to mitigate seasonal climate changes. To replicate this case, a lake was inserted into North America and a climate model was run using varying carbon dioxide levels. The model runs concluded that while the lake did reduce the seasonality of the region greater than just an increase in carbon dioxide, the addition of a large lake was unable to reduce the seasonality to the levels shown by the floral and faunal data. Ocean heat transport The transport of heat from the tropics to the poles, much like how ocean heat transport functions in modern times, was considered a possibility for the increased temperature and reduced seasonality for the poles. With the increased sea surface temperatures and the increased temperature of the deep ocean water during the early Eocene, one common hypothesis was that due to these increases there would be a greater transport of heat from the tropics to the poles. Simulating these differences, the models produced lower heat transport due to the lower temperature gradients and were unsuccessful in producing an equable climate from only ocean heat transport. Orbital parameters While typically seen as a control on ice growth and seasonality, the orbital parameters were theorized as a possible control on continental temperatures and seasonality. Simulating the Eocene by using an ice free planet, eccentricity, obliquity, and precession were modified in different model runs to determine all the possible different scenarios that could occur and their effects on temperature. One particular case led to warmer winters and cooler summer by up to 30% in the North American continent, and it reduced the seasonal variation of temperature by up to 75%. While orbital parameters did not produce the warming at the poles, the parameters did show a great effect on seasonality and needed to be considered. Polar stratospheric clouds Another method considered for producing the warm polar temperatures were polar stratospheric clouds. Polar stratospheric clouds are clouds that occur in the lower stratosphere at very low temperatures. Polar stratospheric clouds have a great impact on radiative forcing. Due to their minimal albedo properties and their optical thickness, polar stratospheric clouds act similar to a greenhouse gas and traps outgoing longwave radiation. Different types of polar stratospheric clouds occur in the atmosphere: polar stratospheric clouds that are created due to interactions with nitric or sulfuric acid and water (Type I) or polar stratospheric clouds that are created with only water ice (Type II).Methane is an important factor in the creation of the primary Type II polar stratospheric clouds that were created in the early Eocene. Since water vapor is the only supporting substance used in Type II polar stratospheric clouds, the presence of water vapor in the lower stratosphere is necessary where in most situations the presence of water vapor in the lower stratosphere is rare. When methane is oxidized, a significant amount of water vapor is released. Another requirement for polar stratospheric clouds is cold temperatures to ensure condensation and cloud production. Polar stratospheric cloud production, since it requires the cold temperatures, is usually limited to nighttime and winter conditions. With this combination of wetter and colder conditions in the lower stratosphere, polar stratospheric clouds could have formed over wide areas in Polar Regions.To test the polar stratospheric clouds effects on the Eocene climate, models were run comparing the effects of polar stratospheric clouds at the poles to an increase in atmospheric carbon dioxide. The polar stratospheric clouds had a warming effect on the poles, increasing temperatures by up to 20 °C in the winter months. A multitude of feedbacks also occurred in the models due to the polar stratospheric clouds' presence. Any ice growth was slowed immensely and would lead to any present ice melting. Only the poles were affected with the change in temperature and the tropics were unaffected, which with an increase in atmospheric carbon dioxide would also cause the tropics to increase in temperature. Due to the warming of the troposphere from the increased greenhouse effect of the polar stratospheric clouds, the stratosphere would cool and would potentially increase the amount of polar stratospheric clouds. While the polar stratospheric clouds could explain the reduction of the equator to pole temperature gradient and the increased temperatures at the poles during the early Eocene, there are a few drawbacks to maintaining polar stratospheric clouds for an extended period of time. Separate model runs were used to determine the sustainability of the polar stratospheric clouds. It was determined that in order to maintain the lower stratospheric water vapor, methane would need to be continually released and sustained. In addition, the amounts of ice and condensation nuclei would need to be high in order for the polar stratospheric cloud to sustain itself and eventually expand. Middle Eocene The Eocene is not only known for containing the warmest period during the Cenozoic; it also marked the decline into an icehouse climate and the rapid expansion of the Antarctic ice sheet. The transition from a warming climate into a cooling climate began at around 49 Ma. Isotopes of carbon and oxygen indicate a shift to a global cooling climate. The cause of the cooling has been attributed to a significant decrease of >2,000 ppm in atmospheric carbon dioxide concentrations. One proposed cause of the reduction in carbon dioxide during the warming to cooling transition was the azolla event. With the equable climate during the early Eocene, warm temperatures in the arctic allowed for the growth of azolla, which is a floating aquatic fern, on the Arctic Ocean. The significantly high amounts of carbon dioxide also acted to facilitate azolla blooms across the Arctic Ocean. Compared to current carbon dioxide levels, these azolla grew rapidly in the enhanced carbon dioxide levels found in the early Eocene. The isolation of the Arctic Ocean, evidenced by euxinia that occurred at this time, led to stagnant waters and as the azolla sank to the sea floor, they became part of the sediments on the seabed and effectively sequestered the carbon by locking it out of the atmosphere for good. The ability for the azolla to sequester carbon is exceptional, and the enhanced burial of azolla could have had a significant effect on the world atmospheric carbon content and may have been the event to begin the transition into an ice house climate. The azolla event could have led to a draw down of atmospheric carbon dioxide of up to 470 ppm. Assuming the carbon dioxide concentrations were at 900 ppmv prior to the Azolla Event they would have dropped to 430 ppmv, or 30 ppmv more than they are today, after the Azolla Event. This cooling trend at the end of the Early Eocene Climatic Optimum has also been proposed to have been caused by increased siliceous plankton productivity and marine carbon burial, which also helped draw carbon dioxide out of the atmosphere. Cooling after this event continued due to continual decrease in atmospheric carbon dioxide from organic productivity and weathering from mountain building.Global cooling continued until there was a major reversal from cooling to warming in the Bartonian. This warming event, signifying a sudden and temporary reversal of the cooling conditions, is known as the Middle Eocene Climatic Optimum (MECO). At around 41.5 Ma, stable isotopic analysis of samples from Southern Ocean drilling sites indicated a warming event for 600,000 years. A similar shift in carbon isotopes is known from the Northern Hemisphere in the Scaglia Limestones of Italy. Oxygen isotope analysis showed a large negative change in the proportion of heavier oxygen isotopes to lighter oxygen isotopes, which indicates an increase in global temperatures. The warming is considered to be primarily due to carbon dioxide increases, because carbon isotope signatures rule out major methane release during this short-term warming. A sharp increase in atmospheric carbon dioxide was observed with a maximum of 4,000 ppm: the highest amount of atmospheric carbon dioxide detected during the Eocene. Other studies suggest a more modest rise in carbon dioxide levels. The increase in atmospheric carbon dioxide has also been hypothesised to have been driven by increased seafloor spreading rates and metamorphic decarbonation reactions between Australia and Antarctica and increased amounts of volcanism in the region. One possible cause of atmospheric carbon dioxide increase could have been a sudden increase due to metamorphic release due to continental drift and collision of India with Asia and the resulting formation of the Himalayas; however, data on the exact timing of metamorphic release of atmospheric carbon dioxide is not well resolved in the data. Recent studies have mentioned, however, that the removal of the ocean between Asia and India could have released significant amounts of carbon dioxide. Another hypothesis still implicates a diminished negative feedback of silicate weathering as a result of continental rocks having become less weatherable during the warm Early and Middle Eocene, allowing volcanically released carbon dioxide to persist in the atmosphere for longer. Yet another explanation hypothesises that MECO warming was caused by the simultaneous occurrence of minima in both the 400 kyr and 2.4 Myr eccentricity cycles. During the MECO, sea surface temperatures in the Tethys Ocean jumped to 32-36 °C, and Tethyan seawater became more dysoxic. A decline in carbonate accumulation at ocean depths of greater than three kilometres took place synchronously with the peak of the MECO, signifying ocean acidification took place in the deep ocean. An abrupt decrease in lakewater salinity in western North America occurred during this warming interval. This warming is short lived, as benthic oxygen isotope records indicate a return to cooling at ~40 Ma. Late Eocene At the end of the Middle Eocene Climatic Optimum, cooling and the carbon dioxide drawdown continued through the late Eocene and into the Eocene–Oligocene transition around 34 Ma. The post-MECO cooling brought with it a major aridification trend in Asia. The cooling during the initial stages of the opening of the Drake Passage ~38.5 Ma was not global, as evidenced by an absence of cooling in the North Atlantic. During the cooling period, benthic oxygen isotopes show the possibility of ice creation and ice increase during this later cooling. The end of the Eocene and beginning of the Oligocene is marked with the massive expansion of area of the Antarctic ice sheet that was a major step into the icehouse climate. Multiple proxies, such as oxygen isotopes and alkenones, indicate that at the Eocene–Oligocene transition, the atmospheric carbon dioxide concentration had decreased to around 750–800 ppm, approximately twice that of present levels. Along with the decrease of atmospheric carbon dioxide reducing the global temperature, orbital factors in ice creation can be seen with 100,000-year and 400,000-year fluctuations in benthic oxygen isotope records. Another major contribution to the expansion of the ice sheet was the creation of the Antarctic Circumpolar Current. The creation of the Antarctic circumpolar current would isolate the cold water around the Antarctic, which would reduce heat transport to the Antarctic along with creating ocean gyres that result in the upwelling of colder bottom waters. The issue with this hypothesis of the consideration of this being a factor for the Eocene-Oligocene transition is the timing of the creation of the circulation is uncertain. For Drake Passage, sediments indicate the opening occurred ~41 Ma while tectonics indicate that this occurred ~32 Ma. Flora During the early-middle Eocene, forests covered most of the Earth including the poles. Tropical forests extended across much of modern Africa, South America, Central America, India, South-east Asia and China. Paratropical forests grew over North America, Europe and Russia, with broad-leafed evergreen and broad-leafed deciduous forests at higher latitudes.Polar forests were quite extensive. Fossils and even preserved remains of trees such as swamp cypress and dawn redwood from the Eocene have been found on Ellesmere Island in the Arctic. Even at that time, Ellesmere Island was only a few degrees in latitude further south than it is today. Fossils of subtropical and even tropical trees and plants from the Eocene also have been found in Greenland and Alaska. Tropical rainforests grew as far north as northern North America and Europe.Palm trees were growing as far north as Alaska and northern Europe during the early Eocene, although they became less abundant as the climate cooled. Dawn redwoods were far more extensive as well.The earliest definitive Eucalyptus fossils were dated from 51.9 Mya, and were found in the Laguna del Hunco deposit in Chubut province in Argentina.Cooling began mid-period, and by the end of the Eocene continental interiors had begun to dry, with forests thinning considerably in some areas. The newly evolved grasses were still confined to river banks and lake shores, and had not yet expanded into plains and savannas.The cooling also brought seasonal changes. Deciduous trees, better able to cope with large temperature changes, began to overtake evergreen tropical species. By the end of the period, deciduous forests covered large parts of the northern continents, including North America, Eurasia and the Arctic, and rainforests held on only in equatorial South America, Africa, India and Australia.Antarctica began the Eocene fringed with a warm temperate to sub-tropical rainforest. Pollen found in Prydz Bay from the Eocene suggest taiga forest existed there. It became much colder as the period progressed; the heat-loving tropical flora was wiped out, and by the beginning of the Oligocene, the continent hosted deciduous forests and vast stretches of tundra. Fauna During the Eocene, plants and marine faunas became quite modern. Many modern bird orders first appeared in the Eocene. The Eocene oceans were warm and teeming with fish and other sea life. Mammals The oldest known fossils of most of the modern mammal orders appear within a brief period during the early Eocene. At the beginning of the Eocene, several new mammal groups arrived in North America. These modern mammals, like artiodactyls, perissodactyls, and primates, had features like long, thin legs, feet, and hands capable of grasping, as well as differentiated teeth adapted for chewing. Dwarf forms reigned. All the members of the new mammal orders were small, under 10 kg; based on comparisons of tooth size, Eocene mammals were only 60% of the size of the primitive Palaeocene mammals that preceded them. They were also smaller than the mammals that followed them. It is assumed that the hot Eocene temperatures favored smaller animals that were better able to manage the heat.Both groups of modern ungulates (hoofed animals) became prevalent because of a major radiation between Europe and North America, along with carnivorous ungulates like Mesonyx. Early forms of many other modern mammalian orders appeared, including horses (most notably the Eohippus), bats, proboscidians (elephants), primates, rodents, and marsupials. Older primitive forms of mammals declined in variety and importance. Important Eocene land fauna fossil remains have been found in western North America, Europe, Patagonia, Egypt, and southeast Asia. Marine fauna are best known from South Asia and the southeast United States.Established megafauna of the Eocene include the Uintatherium, Arsinoitherium, and brontotheres, in which the former two, unlike the latter, did not belong to ungulates but groups that became extinct shortly after their establishments. Large terrestrial mammalian predators began to take form as the terrestrial carnivores like the Hyaenodon and Daphoenus (the earliest lineage of a once-successful predatory family known as bear dogs). Entelodonts meanwhile established themselves as some of the largest omnivores. The first nimravids, including Dinictis, established themselves as amongst the first feliforms to appear. Their groups became highly successful and continued to live past the Eocene. Basilosaurus is a very well-known Eocene whale, but whales as a group had become very diverse during the Eocene, which is when the major transitions from being terrestrial to fully aquatic in cetaceans occurred. The first sirenians were evolving at this time, and would eventually evolve into the extant manatees and dugongs. It is thought that millions of years after the Cretaceous-Paleogene extinction event, brain sizes of mammals now started to increase, "likely driven by a need for greater cognition in increasingly complex environments". Birds Eocene birds include some enigmatic groups with resemblances to modern forms, some of which continued from the Paleocene. Bird taxa of the Eocene include carnivorous psittaciforms, such as Messelasturidae, Halcyornithidae, large flightless forms such as Gastornis and Eleutherornis, long legged falcon Masillaraptor, ancient galliforms such as Gallinuloides, putative rail relatives of the family Songziidae, various pseudotooth birds such as Gigantornis, the ibis relative Rhynchaeites, primitive swifts of the genus Aegialornis, and primitive penguins such as Archaeospheniscus and Inkayacu. Reptiles Reptile fossils from this time, such as fossils of pythons and turtles, are abundant. Insects and arachnids Several rich fossil insect faunas are known from the Eocene, notably the Baltic amber found mainly along the south coast of the Baltic Sea, amber from the Paris Basin, France, the Fur Formation, Denmark, and the Bembridge Marls from the Isle of Wight, England. Insects found in Eocene deposits mostly belong to genera that exist today, though their range has often shifted since the Eocene. For instance the bibionid genus Plecia is common in fossil faunas from presently temperate areas, but only lives in the tropics and subtropics today. Gallery See also Bolca in Italy List of fossil sites (with link directory) London Clay Messel pit in Germany Wadi El Hitan in Egypt Notes References Further reading Ogg, Jim; June, 2004, Overview of Global Boundary Stratotype Sections and Points (GSSP's) Global Stratotype Sections and Points Accessed April 30, 2006. Stanley, Steven M. Earth System History. New York: W.H. Freeman and Company, 1999. ISBN 0-7167-2882-6 External links PaleoMap Project Paleos Eocene page PBS Deep Time: Eocene Eocene and Oligocene Fossils The UPenn Fossil Forest Project, focusing on the Eocene polar forests in Ellesmere Island, Canada Basilosaurus Primitive Eocene Whales Basilosaurus - The plesiosaur that wasn't.... Detailed maps of Tertiary Western North America Map of Eocene Earth Eocene Microfossils: 60+ images of Foraminifera Eocene Epoch. (2011). In Encyclopædia Britannica. Retrieved from Eocene Epoch \| geochronology	has part(s)	{ "answer_start": [ 3192 ], "text": [ "Priabonian" ] }
The Eocene (IPA: EE-ə-seen, EE-oh-) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name Eocene comes from the Ancient Greek ἠώς (ēṓs, "dawn") and καινός (kainós, "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the Grande Coupure (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the epoch are well identified, though their exact dates are slightly uncertain. Etymology The term "Eocene" is derived from Ancient Greek ἠώς eos meaning "dawn", and καινός kainos meaning "new" or "recent", as the epoch saw the dawn of recent, or modern, life. Scottish geologist Charles Lyell (ignoring the Quaternary) had divided the Tertiary Epoch into the Eocene, Miocene, Pliocene, and New Pliocene (Holocene) Periods in 1833. British geologist John Phillips had proposed the Cenozoic in 1840 in place of the Tertiary, and Austrian paleontologist Moritz Hörnes had introduced the Paleogene for the Eocene and Neogene for the Miocene and Pliocene in 1853. After decades of inconsistent usage, the newly formed International Commission on Stratigraphy (ICS), in 1969, standardized stratigraphy based on the prevailing opinions in Europe: the Cenozoic Era subdivided into the Tertiary and Quaternary sub-eras, and the Tertiary subdivided into the Paleogene and Neogene periods. In 1978, the Paleogene was officially defined as the Paleocene, Eocene, and Oligocene epochs; and the Neogene as the Miocene and Pliocene epochs. In 1989, Tertiary and Quaternary were removed from the time scale due to the arbitrary nature of their boundary, but Quaternary was reinstated in 2009. Geology Boundaries The beginning of the Eocene is marked by the Paleocene–Eocene Thermal Maximum, a short period of intense warming and ocean acidification brought about by the release of carbon en masse into the atmosphere and ocean systems, which led to a mass extinction of 30–50% of benthic foraminifera–single-celled species which are used as bioindicators of the health of a marine ecosystem—one of the largest in the Cenozoic. This event happened around 55.8 mya, and was one of the most significant periods of global change during the Cenozoic.The end of the Eocene was marked by the Eocene–Oligocene extinction event, also known as the Grande Coupure. Stratigraphy The Eocene is conventionally divided into early (56–47.8 Ma), middle (47.8–38 Ma), and late (38–33.9 Ma) subdivisions. The corresponding rocks are referred to as lower, middle, and upper Eocene. The Ypresian Stage constitutes the lower, the Priabonian Stage the upper; and the Lutetian and Bartonian stages are united as the middle Eocene. Palaeogeography and tectonics During the Eocene, the continents continued to drift toward their present positions. At the beginning of the period, Australia and Antarctica remained connected, and warm equatorial currents may have mixed with colder Antarctic waters, distributing the heat around the planet and keeping global temperatures high. When Australia split from the southern continent around 45 Ma, the warm equatorial currents were routed away from Antarctica. An isolated cold water channel developed between the two continents. However, modeling results call into question the thermal isolation model for late Eocene cooling, and decreasing carbon dioxide levels in the atmosphere may have been more important. Once the Antarctic region began to cool down, the ocean surrounding Antarctica began to freeze, sending cold water and icefloes north and reinforcing the cooling.The northern supercontinent of Laurasia began to fragment, as Europe, Greenland and North America drifted apart.In western North America, the Laramide Orogeny came to an end in the Eocene, and compression was replaced with crustal extension that ultimately gave rise to the Basin and Range Province. Huge lakes formed in the high flat basins among uplifts, resulting in the deposition of the Green River Formation lagerstätte.At about 35 Ma, an asteroid impact on the eastern coast of North America formed the Chesapeake Bay impact crater.In Europe, the Tethys Sea finally disappeared, while the uplift of the Alps isolated its final remnant, the Mediterranean, and created another shallow sea with island archipelagos to the north. Though the North Atlantic was opening, a land connection appears to have remained between North America and Europe since the faunas of the two regions are very similar.Eurasia was separated in three different landmasses 50 Ma; Western Europe, Balkanatolia and Asia. About 40 Ma, Balkanatolia and Asia were connected, while Europe was connected 34 Ma.India collided with Asia, folding to initiate formation of the Himalayas. India collided with the Kohistan–Ladakh Arc around 50.2 Ma and with Karakoram around 40.4 Ma, with the final collision between Asia and India occurring ~40 Ma. Climate The Eocene Epoch contained a wide variety of different climate conditions that includes the warmest climate in the Cenozoic Era, and arguably the warmest time interval since the Permian-Triassic mass extinction and Early Triassic, and ends in an icehouse climate. The evolution of the Eocene climate began with warming after the end of the Paleocene–Eocene Thermal Maximum (PETM) at 56 Ma to a maximum during the Eocene Optimum at around 49 Ma. Recent study show elevation-dependent temperature changes during the Eocene hothouse. During this period of time, little to no ice was present on Earth with a smaller difference in temperature from the equator to the poles. Because of this the maximum sea level was 150 meters higher than current levels. Following the maximum was a descent into an icehouse climate from the Eocene Optimum to the Eocene-Oligocene transition at 34 Ma. During this decrease, ice began to reappear at the poles, and the Eocene-Oligocene transition is the period of time where the Antarctic ice sheet began to rapidly expand. Early Eocene Greenhouse gases, in particular carbon dioxide and methane, played a significant role during the Eocene in controlling the surface temperature. The end of the PETM was met with very large sequestration of carbon dioxide into the forms of methane clathrate, coal, and crude oil at the bottom of the Arctic Ocean, that reduced the atmospheric carbon dioxide. This event was similar in magnitude to the massive release of greenhouse gasses at the beginning of the PETM, and it is hypothesized that the sequestration was mainly due to organic carbon burial and weathering of silicates. For the early Eocene there is much discussion on how much carbon dioxide was in the atmosphere. This is due to numerous proxies representing different atmospheric carbon dioxide content. For example, diverse geochemical and paleontological proxies indicate that at the maximum of global warmth the atmospheric carbon dioxide values were at 700–900 ppm while other proxies such as pedogenic (soil building) carbonate and marine boron isotopes indicate large changes of carbon dioxide of over 2,000 ppm over periods of time of less than 1 million years. Sources for this large influx of carbon dioxide could be attributed to volcanic out-gassing due to North Atlantic rifting or oxidation of methane stored in large reservoirs deposited from the PETM event in the sea floor or wetland environments. For contrast, today the carbon dioxide levels are at 400 ppm or 0.04%. At about the beginning of the Eocene Epoch (55.8–33.9 Ma) the amount of oxygen in the earth's atmosphere more or less doubled.During the early Eocene, methane was another greenhouse gas that had a drastic effect on the climate. The warming effect of one ton of methane dimensions unspecified is approximately 30 times the warming effect of one ton of carbon on a 100-year scale (i.e., methane has a global warming potential of 29.8±11). Most of the methane released to the atmosphere during this period of time would have been from wetlands, swamps, and forests. The atmospheric methane concentration today is 0.000179% or 1.79 ppmv. As a result of the warmer climate and the sea level rise associated with the early Eocene, more wetlands, more forests, and more coal deposits would have been available for methane release. If we compare the early Eocene production of methane to current levels of atmospheric methane, the early Eocene would have produced triple the amount of methane. The warm temperatures during the early Eocene could have increased methane production rates, and methane that is released into the atmosphere would in turn warm the troposphere, cool the stratosphere, and produce water vapor and carbon dioxide through oxidation. Biogenic production of methane produces carbon dioxide and water vapor along with the methane, as well as yielding infrared radiation. The breakdown of methane in an atmosphere containing oxygen produces carbon monoxide, water vapor and infrared radiation. The carbon monoxide is not stable, so it eventually becomes carbon dioxide and in doing so releases yet more infrared radiation. Water vapor traps more infrared than does carbon dioxide. Hyperthermals through the early Eocene During the warming in the early Eocene between 55 and 52 Ma, there were a series of short-term changes of carbon isotope composition in the ocean. These isotope changes occurred due to the release of carbon from the ocean into the atmosphere that led to a temperature increase of 4–8 °C (7.2–14.4 °F) at the surface of the ocean. These hyperthermals led to increased perturbations in planktonic and benthic foraminifera, with a higher rate of sedimentation as a consequence of the warmer temperatures. Recent analysis of and research into these hyperthermals in the early Eocene has led to hypotheses that the hyperthermals are based on orbital parameters, in particular eccentricity and obliquity. The hyperthermals in the early Eocene, notably the Palaeocene–Eocene Thermal Maximum (PETM), the Eocene Thermal Maximum 2 (ETM2), and the Eocene Thermal Maximum 3 (ETM3), were analyzed and found that orbital control may have had a role in triggering the ETM2 and ETM3. Equable climate problem One of the unique features of the Eocene's climate as mentioned before was the equable and homogeneous climate that existed in the early parts of the Eocene. A multitude of proxies support the presence of a warmer equable climate being present during this period of time. A few of these proxies include the presence of fossils native to warm climates, such as crocodiles, located in the higher latitudes, the presence in the high latitudes of frost-intolerant flora such as palm trees which cannot survive during sustained freezes, and fossils of snakes found in the tropics that would require much higher average temperatures to sustain them. TEX86 BAYSPAR measurements indicate extremely high sea surface temperatures of 40 °C (104 °F) to 45 °C (113 °F) at low latitudes, although clumped isotope analyses point to a maximum low latitude sea surface temperature of 36.3 °C (97.3 °F) ± 1.9 °C (35.4 °F) during the Early Eocene Climatic Optimum. Relative to present-day values, bottom water temperatures are 10 °C (18 °F) higher according to isotope proxies. With these bottom water temperatures, temperatures in areas where deep water forms near the poles are unable to be much cooler than the bottom water temperatures.An issue arises, however, when trying to model the Eocene and reproduce the results that are found with the proxy data. Using all different ranges of greenhouse gasses that occurred during the early Eocene, models were unable to produce the warming that was found at the poles and the reduced seasonality that occurs with winters at the poles being substantially warmer. The models, while accurately predicting the tropics, tend to produce significantly cooler temperatures of up to 20 °C (36 °F) colder than the actual determined temperature at the poles. This error has been classified as the "equable climate problem". To solve this problem, the solution would involve finding a process to warm the poles without warming the tropics. Some hypotheses and tests which attempt to find the process are listed below. Large lakes Due to the nature of water as opposed to land, less temperature variability would be present if a large body of water is also present. In an attempt to try to mitigate the cooling polar temperatures, large lakes were proposed to mitigate seasonal climate changes. To replicate this case, a lake was inserted into North America and a climate model was run using varying carbon dioxide levels. The model runs concluded that while the lake did reduce the seasonality of the region greater than just an increase in carbon dioxide, the addition of a large lake was unable to reduce the seasonality to the levels shown by the floral and faunal data. Ocean heat transport The transport of heat from the tropics to the poles, much like how ocean heat transport functions in modern times, was considered a possibility for the increased temperature and reduced seasonality for the poles. With the increased sea surface temperatures and the increased temperature of the deep ocean water during the early Eocene, one common hypothesis was that due to these increases there would be a greater transport of heat from the tropics to the poles. Simulating these differences, the models produced lower heat transport due to the lower temperature gradients and were unsuccessful in producing an equable climate from only ocean heat transport. Orbital parameters While typically seen as a control on ice growth and seasonality, the orbital parameters were theorized as a possible control on continental temperatures and seasonality. Simulating the Eocene by using an ice free planet, eccentricity, obliquity, and precession were modified in different model runs to determine all the possible different scenarios that could occur and their effects on temperature. One particular case led to warmer winters and cooler summer by up to 30% in the North American continent, and it reduced the seasonal variation of temperature by up to 75%. While orbital parameters did not produce the warming at the poles, the parameters did show a great effect on seasonality and needed to be considered. Polar stratospheric clouds Another method considered for producing the warm polar temperatures were polar stratospheric clouds. Polar stratospheric clouds are clouds that occur in the lower stratosphere at very low temperatures. Polar stratospheric clouds have a great impact on radiative forcing. Due to their minimal albedo properties and their optical thickness, polar stratospheric clouds act similar to a greenhouse gas and traps outgoing longwave radiation. Different types of polar stratospheric clouds occur in the atmosphere: polar stratospheric clouds that are created due to interactions with nitric or sulfuric acid and water (Type I) or polar stratospheric clouds that are created with only water ice (Type II).Methane is an important factor in the creation of the primary Type II polar stratospheric clouds that were created in the early Eocene. Since water vapor is the only supporting substance used in Type II polar stratospheric clouds, the presence of water vapor in the lower stratosphere is necessary where in most situations the presence of water vapor in the lower stratosphere is rare. When methane is oxidized, a significant amount of water vapor is released. Another requirement for polar stratospheric clouds is cold temperatures to ensure condensation and cloud production. Polar stratospheric cloud production, since it requires the cold temperatures, is usually limited to nighttime and winter conditions. With this combination of wetter and colder conditions in the lower stratosphere, polar stratospheric clouds could have formed over wide areas in Polar Regions.To test the polar stratospheric clouds effects on the Eocene climate, models were run comparing the effects of polar stratospheric clouds at the poles to an increase in atmospheric carbon dioxide. The polar stratospheric clouds had a warming effect on the poles, increasing temperatures by up to 20 °C in the winter months. A multitude of feedbacks also occurred in the models due to the polar stratospheric clouds' presence. Any ice growth was slowed immensely and would lead to any present ice melting. Only the poles were affected with the change in temperature and the tropics were unaffected, which with an increase in atmospheric carbon dioxide would also cause the tropics to increase in temperature. Due to the warming of the troposphere from the increased greenhouse effect of the polar stratospheric clouds, the stratosphere would cool and would potentially increase the amount of polar stratospheric clouds. While the polar stratospheric clouds could explain the reduction of the equator to pole temperature gradient and the increased temperatures at the poles during the early Eocene, there are a few drawbacks to maintaining polar stratospheric clouds for an extended period of time. Separate model runs were used to determine the sustainability of the polar stratospheric clouds. It was determined that in order to maintain the lower stratospheric water vapor, methane would need to be continually released and sustained. In addition, the amounts of ice and condensation nuclei would need to be high in order for the polar stratospheric cloud to sustain itself and eventually expand. Middle Eocene The Eocene is not only known for containing the warmest period during the Cenozoic; it also marked the decline into an icehouse climate and the rapid expansion of the Antarctic ice sheet. The transition from a warming climate into a cooling climate began at around 49 Ma. Isotopes of carbon and oxygen indicate a shift to a global cooling climate. The cause of the cooling has been attributed to a significant decrease of >2,000 ppm in atmospheric carbon dioxide concentrations. One proposed cause of the reduction in carbon dioxide during the warming to cooling transition was the azolla event. With the equable climate during the early Eocene, warm temperatures in the arctic allowed for the growth of azolla, which is a floating aquatic fern, on the Arctic Ocean. The significantly high amounts of carbon dioxide also acted to facilitate azolla blooms across the Arctic Ocean. Compared to current carbon dioxide levels, these azolla grew rapidly in the enhanced carbon dioxide levels found in the early Eocene. The isolation of the Arctic Ocean, evidenced by euxinia that occurred at this time, led to stagnant waters and as the azolla sank to the sea floor, they became part of the sediments on the seabed and effectively sequestered the carbon by locking it out of the atmosphere for good. The ability for the azolla to sequester carbon is exceptional, and the enhanced burial of azolla could have had a significant effect on the world atmospheric carbon content and may have been the event to begin the transition into an ice house climate. The azolla event could have led to a draw down of atmospheric carbon dioxide of up to 470 ppm. Assuming the carbon dioxide concentrations were at 900 ppmv prior to the Azolla Event they would have dropped to 430 ppmv, or 30 ppmv more than they are today, after the Azolla Event. This cooling trend at the end of the Early Eocene Climatic Optimum has also been proposed to have been caused by increased siliceous plankton productivity and marine carbon burial, which also helped draw carbon dioxide out of the atmosphere. Cooling after this event continued due to continual decrease in atmospheric carbon dioxide from organic productivity and weathering from mountain building.Global cooling continued until there was a major reversal from cooling to warming in the Bartonian. This warming event, signifying a sudden and temporary reversal of the cooling conditions, is known as the Middle Eocene Climatic Optimum (MECO). At around 41.5 Ma, stable isotopic analysis of samples from Southern Ocean drilling sites indicated a warming event for 600,000 years. A similar shift in carbon isotopes is known from the Northern Hemisphere in the Scaglia Limestones of Italy. Oxygen isotope analysis showed a large negative change in the proportion of heavier oxygen isotopes to lighter oxygen isotopes, which indicates an increase in global temperatures. The warming is considered to be primarily due to carbon dioxide increases, because carbon isotope signatures rule out major methane release during this short-term warming. A sharp increase in atmospheric carbon dioxide was observed with a maximum of 4,000 ppm: the highest amount of atmospheric carbon dioxide detected during the Eocene. Other studies suggest a more modest rise in carbon dioxide levels. The increase in atmospheric carbon dioxide has also been hypothesised to have been driven by increased seafloor spreading rates and metamorphic decarbonation reactions between Australia and Antarctica and increased amounts of volcanism in the region. One possible cause of atmospheric carbon dioxide increase could have been a sudden increase due to metamorphic release due to continental drift and collision of India with Asia and the resulting formation of the Himalayas; however, data on the exact timing of metamorphic release of atmospheric carbon dioxide is not well resolved in the data. Recent studies have mentioned, however, that the removal of the ocean between Asia and India could have released significant amounts of carbon dioxide. Another hypothesis still implicates a diminished negative feedback of silicate weathering as a result of continental rocks having become less weatherable during the warm Early and Middle Eocene, allowing volcanically released carbon dioxide to persist in the atmosphere for longer. Yet another explanation hypothesises that MECO warming was caused by the simultaneous occurrence of minima in both the 400 kyr and 2.4 Myr eccentricity cycles. During the MECO, sea surface temperatures in the Tethys Ocean jumped to 32-36 °C, and Tethyan seawater became more dysoxic. A decline in carbonate accumulation at ocean depths of greater than three kilometres took place synchronously with the peak of the MECO, signifying ocean acidification took place in the deep ocean. An abrupt decrease in lakewater salinity in western North America occurred during this warming interval. This warming is short lived, as benthic oxygen isotope records indicate a return to cooling at ~40 Ma. Late Eocene At the end of the Middle Eocene Climatic Optimum, cooling and the carbon dioxide drawdown continued through the late Eocene and into the Eocene–Oligocene transition around 34 Ma. The post-MECO cooling brought with it a major aridification trend in Asia. The cooling during the initial stages of the opening of the Drake Passage ~38.5 Ma was not global, as evidenced by an absence of cooling in the North Atlantic. During the cooling period, benthic oxygen isotopes show the possibility of ice creation and ice increase during this later cooling. The end of the Eocene and beginning of the Oligocene is marked with the massive expansion of area of the Antarctic ice sheet that was a major step into the icehouse climate. Multiple proxies, such as oxygen isotopes and alkenones, indicate that at the Eocene–Oligocene transition, the atmospheric carbon dioxide concentration had decreased to around 750–800 ppm, approximately twice that of present levels. Along with the decrease of atmospheric carbon dioxide reducing the global temperature, orbital factors in ice creation can be seen with 100,000-year and 400,000-year fluctuations in benthic oxygen isotope records. Another major contribution to the expansion of the ice sheet was the creation of the Antarctic Circumpolar Current. The creation of the Antarctic circumpolar current would isolate the cold water around the Antarctic, which would reduce heat transport to the Antarctic along with creating ocean gyres that result in the upwelling of colder bottom waters. The issue with this hypothesis of the consideration of this being a factor for the Eocene-Oligocene transition is the timing of the creation of the circulation is uncertain. For Drake Passage, sediments indicate the opening occurred ~41 Ma while tectonics indicate that this occurred ~32 Ma. Flora During the early-middle Eocene, forests covered most of the Earth including the poles. Tropical forests extended across much of modern Africa, South America, Central America, India, South-east Asia and China. Paratropical forests grew over North America, Europe and Russia, with broad-leafed evergreen and broad-leafed deciduous forests at higher latitudes.Polar forests were quite extensive. Fossils and even preserved remains of trees such as swamp cypress and dawn redwood from the Eocene have been found on Ellesmere Island in the Arctic. Even at that time, Ellesmere Island was only a few degrees in latitude further south than it is today. Fossils of subtropical and even tropical trees and plants from the Eocene also have been found in Greenland and Alaska. Tropical rainforests grew as far north as northern North America and Europe.Palm trees were growing as far north as Alaska and northern Europe during the early Eocene, although they became less abundant as the climate cooled. Dawn redwoods were far more extensive as well.The earliest definitive Eucalyptus fossils were dated from 51.9 Mya, and were found in the Laguna del Hunco deposit in Chubut province in Argentina.Cooling began mid-period, and by the end of the Eocene continental interiors had begun to dry, with forests thinning considerably in some areas. The newly evolved grasses were still confined to river banks and lake shores, and had not yet expanded into plains and savannas.The cooling also brought seasonal changes. Deciduous trees, better able to cope with large temperature changes, began to overtake evergreen tropical species. By the end of the period, deciduous forests covered large parts of the northern continents, including North America, Eurasia and the Arctic, and rainforests held on only in equatorial South America, Africa, India and Australia.Antarctica began the Eocene fringed with a warm temperate to sub-tropical rainforest. Pollen found in Prydz Bay from the Eocene suggest taiga forest existed there. It became much colder as the period progressed; the heat-loving tropical flora was wiped out, and by the beginning of the Oligocene, the continent hosted deciduous forests and vast stretches of tundra. Fauna During the Eocene, plants and marine faunas became quite modern. Many modern bird orders first appeared in the Eocene. The Eocene oceans were warm and teeming with fish and other sea life. Mammals The oldest known fossils of most of the modern mammal orders appear within a brief period during the early Eocene. At the beginning of the Eocene, several new mammal groups arrived in North America. These modern mammals, like artiodactyls, perissodactyls, and primates, had features like long, thin legs, feet, and hands capable of grasping, as well as differentiated teeth adapted for chewing. Dwarf forms reigned. All the members of the new mammal orders were small, under 10 kg; based on comparisons of tooth size, Eocene mammals were only 60% of the size of the primitive Palaeocene mammals that preceded them. They were also smaller than the mammals that followed them. It is assumed that the hot Eocene temperatures favored smaller animals that were better able to manage the heat.Both groups of modern ungulates (hoofed animals) became prevalent because of a major radiation between Europe and North America, along with carnivorous ungulates like Mesonyx. Early forms of many other modern mammalian orders appeared, including horses (most notably the Eohippus), bats, proboscidians (elephants), primates, rodents, and marsupials. Older primitive forms of mammals declined in variety and importance. Important Eocene land fauna fossil remains have been found in western North America, Europe, Patagonia, Egypt, and southeast Asia. Marine fauna are best known from South Asia and the southeast United States.Established megafauna of the Eocene include the Uintatherium, Arsinoitherium, and brontotheres, in which the former two, unlike the latter, did not belong to ungulates but groups that became extinct shortly after their establishments. Large terrestrial mammalian predators began to take form as the terrestrial carnivores like the Hyaenodon and Daphoenus (the earliest lineage of a once-successful predatory family known as bear dogs). Entelodonts meanwhile established themselves as some of the largest omnivores. The first nimravids, including Dinictis, established themselves as amongst the first feliforms to appear. Their groups became highly successful and continued to live past the Eocene. Basilosaurus is a very well-known Eocene whale, but whales as a group had become very diverse during the Eocene, which is when the major transitions from being terrestrial to fully aquatic in cetaceans occurred. The first sirenians were evolving at this time, and would eventually evolve into the extant manatees and dugongs. It is thought that millions of years after the Cretaceous-Paleogene extinction event, brain sizes of mammals now started to increase, "likely driven by a need for greater cognition in increasingly complex environments". Birds Eocene birds include some enigmatic groups with resemblances to modern forms, some of which continued from the Paleocene. Bird taxa of the Eocene include carnivorous psittaciforms, such as Messelasturidae, Halcyornithidae, large flightless forms such as Gastornis and Eleutherornis, long legged falcon Masillaraptor, ancient galliforms such as Gallinuloides, putative rail relatives of the family Songziidae, various pseudotooth birds such as Gigantornis, the ibis relative Rhynchaeites, primitive swifts of the genus Aegialornis, and primitive penguins such as Archaeospheniscus and Inkayacu. Reptiles Reptile fossils from this time, such as fossils of pythons and turtles, are abundant. Insects and arachnids Several rich fossil insect faunas are known from the Eocene, notably the Baltic amber found mainly along the south coast of the Baltic Sea, amber from the Paris Basin, France, the Fur Formation, Denmark, and the Bembridge Marls from the Isle of Wight, England. Insects found in Eocene deposits mostly belong to genera that exist today, though their range has often shifted since the Eocene. For instance the bibionid genus Plecia is common in fossil faunas from presently temperate areas, but only lives in the tropics and subtropics today. Gallery See also Bolca in Italy List of fossil sites (with link directory) London Clay Messel pit in Germany Wadi El Hitan in Egypt Notes References Further reading Ogg, Jim; June, 2004, Overview of Global Boundary Stratotype Sections and Points (GSSP's) Global Stratotype Sections and Points Accessed April 30, 2006. Stanley, Steven M. Earth System History. New York: W.H. Freeman and Company, 1999. ISBN 0-7167-2882-6 External links PaleoMap Project Paleos Eocene page PBS Deep Time: Eocene Eocene and Oligocene Fossils The UPenn Fossil Forest Project, focusing on the Eocene polar forests in Ellesmere Island, Canada Basilosaurus Primitive Eocene Whales Basilosaurus - The plesiosaur that wasn't.... Detailed maps of Tertiary Western North America Map of Eocene Earth Eocene Microfossils: 60+ images of Foraminifera Eocene Epoch. (2011). In Encyclopædia Britannica. Retrieved from Eocene Epoch \| geochronology	significant event	{ "answer_start": [ 2339 ], "text": [ "Paleocene–Eocene Thermal Maximum" ] }
The Eocene (IPA: EE-ə-seen, EE-oh-) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name Eocene comes from the Ancient Greek ἠώς (ēṓs, "dawn") and καινός (kainós, "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the Grande Coupure (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the epoch are well identified, though their exact dates are slightly uncertain. Etymology The term "Eocene" is derived from Ancient Greek ἠώς eos meaning "dawn", and καινός kainos meaning "new" or "recent", as the epoch saw the dawn of recent, or modern, life. Scottish geologist Charles Lyell (ignoring the Quaternary) had divided the Tertiary Epoch into the Eocene, Miocene, Pliocene, and New Pliocene (Holocene) Periods in 1833. British geologist John Phillips had proposed the Cenozoic in 1840 in place of the Tertiary, and Austrian paleontologist Moritz Hörnes had introduced the Paleogene for the Eocene and Neogene for the Miocene and Pliocene in 1853. After decades of inconsistent usage, the newly formed International Commission on Stratigraphy (ICS), in 1969, standardized stratigraphy based on the prevailing opinions in Europe: the Cenozoic Era subdivided into the Tertiary and Quaternary sub-eras, and the Tertiary subdivided into the Paleogene and Neogene periods. In 1978, the Paleogene was officially defined as the Paleocene, Eocene, and Oligocene epochs; and the Neogene as the Miocene and Pliocene epochs. In 1989, Tertiary and Quaternary were removed from the time scale due to the arbitrary nature of their boundary, but Quaternary was reinstated in 2009. Geology Boundaries The beginning of the Eocene is marked by the Paleocene–Eocene Thermal Maximum, a short period of intense warming and ocean acidification brought about by the release of carbon en masse into the atmosphere and ocean systems, which led to a mass extinction of 30–50% of benthic foraminifera–single-celled species which are used as bioindicators of the health of a marine ecosystem—one of the largest in the Cenozoic. This event happened around 55.8 mya, and was one of the most significant periods of global change during the Cenozoic.The end of the Eocene was marked by the Eocene–Oligocene extinction event, also known as the Grande Coupure. Stratigraphy The Eocene is conventionally divided into early (56–47.8 Ma), middle (47.8–38 Ma), and late (38–33.9 Ma) subdivisions. The corresponding rocks are referred to as lower, middle, and upper Eocene. The Ypresian Stage constitutes the lower, the Priabonian Stage the upper; and the Lutetian and Bartonian stages are united as the middle Eocene. Palaeogeography and tectonics During the Eocene, the continents continued to drift toward their present positions. At the beginning of the period, Australia and Antarctica remained connected, and warm equatorial currents may have mixed with colder Antarctic waters, distributing the heat around the planet and keeping global temperatures high. When Australia split from the southern continent around 45 Ma, the warm equatorial currents were routed away from Antarctica. An isolated cold water channel developed between the two continents. However, modeling results call into question the thermal isolation model for late Eocene cooling, and decreasing carbon dioxide levels in the atmosphere may have been more important. Once the Antarctic region began to cool down, the ocean surrounding Antarctica began to freeze, sending cold water and icefloes north and reinforcing the cooling.The northern supercontinent of Laurasia began to fragment, as Europe, Greenland and North America drifted apart.In western North America, the Laramide Orogeny came to an end in the Eocene, and compression was replaced with crustal extension that ultimately gave rise to the Basin and Range Province. Huge lakes formed in the high flat basins among uplifts, resulting in the deposition of the Green River Formation lagerstätte.At about 35 Ma, an asteroid impact on the eastern coast of North America formed the Chesapeake Bay impact crater.In Europe, the Tethys Sea finally disappeared, while the uplift of the Alps isolated its final remnant, the Mediterranean, and created another shallow sea with island archipelagos to the north. Though the North Atlantic was opening, a land connection appears to have remained between North America and Europe since the faunas of the two regions are very similar.Eurasia was separated in three different landmasses 50 Ma; Western Europe, Balkanatolia and Asia. About 40 Ma, Balkanatolia and Asia were connected, while Europe was connected 34 Ma.India collided with Asia, folding to initiate formation of the Himalayas. India collided with the Kohistan–Ladakh Arc around 50.2 Ma and with Karakoram around 40.4 Ma, with the final collision between Asia and India occurring ~40 Ma. Climate The Eocene Epoch contained a wide variety of different climate conditions that includes the warmest climate in the Cenozoic Era, and arguably the warmest time interval since the Permian-Triassic mass extinction and Early Triassic, and ends in an icehouse climate. The evolution of the Eocene climate began with warming after the end of the Paleocene–Eocene Thermal Maximum (PETM) at 56 Ma to a maximum during the Eocene Optimum at around 49 Ma. Recent study show elevation-dependent temperature changes during the Eocene hothouse. During this period of time, little to no ice was present on Earth with a smaller difference in temperature from the equator to the poles. Because of this the maximum sea level was 150 meters higher than current levels. Following the maximum was a descent into an icehouse climate from the Eocene Optimum to the Eocene-Oligocene transition at 34 Ma. During this decrease, ice began to reappear at the poles, and the Eocene-Oligocene transition is the period of time where the Antarctic ice sheet began to rapidly expand. Early Eocene Greenhouse gases, in particular carbon dioxide and methane, played a significant role during the Eocene in controlling the surface temperature. The end of the PETM was met with very large sequestration of carbon dioxide into the forms of methane clathrate, coal, and crude oil at the bottom of the Arctic Ocean, that reduced the atmospheric carbon dioxide. This event was similar in magnitude to the massive release of greenhouse gasses at the beginning of the PETM, and it is hypothesized that the sequestration was mainly due to organic carbon burial and weathering of silicates. For the early Eocene there is much discussion on how much carbon dioxide was in the atmosphere. This is due to numerous proxies representing different atmospheric carbon dioxide content. For example, diverse geochemical and paleontological proxies indicate that at the maximum of global warmth the atmospheric carbon dioxide values were at 700–900 ppm while other proxies such as pedogenic (soil building) carbonate and marine boron isotopes indicate large changes of carbon dioxide of over 2,000 ppm over periods of time of less than 1 million years. Sources for this large influx of carbon dioxide could be attributed to volcanic out-gassing due to North Atlantic rifting or oxidation of methane stored in large reservoirs deposited from the PETM event in the sea floor or wetland environments. For contrast, today the carbon dioxide levels are at 400 ppm or 0.04%. At about the beginning of the Eocene Epoch (55.8–33.9 Ma) the amount of oxygen in the earth's atmosphere more or less doubled.During the early Eocene, methane was another greenhouse gas that had a drastic effect on the climate. The warming effect of one ton of methane dimensions unspecified is approximately 30 times the warming effect of one ton of carbon on a 100-year scale (i.e., methane has a global warming potential of 29.8±11). Most of the methane released to the atmosphere during this period of time would have been from wetlands, swamps, and forests. The atmospheric methane concentration today is 0.000179% or 1.79 ppmv. As a result of the warmer climate and the sea level rise associated with the early Eocene, more wetlands, more forests, and more coal deposits would have been available for methane release. If we compare the early Eocene production of methane to current levels of atmospheric methane, the early Eocene would have produced triple the amount of methane. The warm temperatures during the early Eocene could have increased methane production rates, and methane that is released into the atmosphere would in turn warm the troposphere, cool the stratosphere, and produce water vapor and carbon dioxide through oxidation. Biogenic production of methane produces carbon dioxide and water vapor along with the methane, as well as yielding infrared radiation. The breakdown of methane in an atmosphere containing oxygen produces carbon monoxide, water vapor and infrared radiation. The carbon monoxide is not stable, so it eventually becomes carbon dioxide and in doing so releases yet more infrared radiation. Water vapor traps more infrared than does carbon dioxide. Hyperthermals through the early Eocene During the warming in the early Eocene between 55 and 52 Ma, there were a series of short-term changes of carbon isotope composition in the ocean. These isotope changes occurred due to the release of carbon from the ocean into the atmosphere that led to a temperature increase of 4–8 °C (7.2–14.4 °F) at the surface of the ocean. These hyperthermals led to increased perturbations in planktonic and benthic foraminifera, with a higher rate of sedimentation as a consequence of the warmer temperatures. Recent analysis of and research into these hyperthermals in the early Eocene has led to hypotheses that the hyperthermals are based on orbital parameters, in particular eccentricity and obliquity. The hyperthermals in the early Eocene, notably the Palaeocene–Eocene Thermal Maximum (PETM), the Eocene Thermal Maximum 2 (ETM2), and the Eocene Thermal Maximum 3 (ETM3), were analyzed and found that orbital control may have had a role in triggering the ETM2 and ETM3. Equable climate problem One of the unique features of the Eocene's climate as mentioned before was the equable and homogeneous climate that existed in the early parts of the Eocene. A multitude of proxies support the presence of a warmer equable climate being present during this period of time. A few of these proxies include the presence of fossils native to warm climates, such as crocodiles, located in the higher latitudes, the presence in the high latitudes of frost-intolerant flora such as palm trees which cannot survive during sustained freezes, and fossils of snakes found in the tropics that would require much higher average temperatures to sustain them. TEX86 BAYSPAR measurements indicate extremely high sea surface temperatures of 40 °C (104 °F) to 45 °C (113 °F) at low latitudes, although clumped isotope analyses point to a maximum low latitude sea surface temperature of 36.3 °C (97.3 °F) ± 1.9 °C (35.4 °F) during the Early Eocene Climatic Optimum. Relative to present-day values, bottom water temperatures are 10 °C (18 °F) higher according to isotope proxies. With these bottom water temperatures, temperatures in areas where deep water forms near the poles are unable to be much cooler than the bottom water temperatures.An issue arises, however, when trying to model the Eocene and reproduce the results that are found with the proxy data. Using all different ranges of greenhouse gasses that occurred during the early Eocene, models were unable to produce the warming that was found at the poles and the reduced seasonality that occurs with winters at the poles being substantially warmer. The models, while accurately predicting the tropics, tend to produce significantly cooler temperatures of up to 20 °C (36 °F) colder than the actual determined temperature at the poles. This error has been classified as the "equable climate problem". To solve this problem, the solution would involve finding a process to warm the poles without warming the tropics. Some hypotheses and tests which attempt to find the process are listed below. Large lakes Due to the nature of water as opposed to land, less temperature variability would be present if a large body of water is also present. In an attempt to try to mitigate the cooling polar temperatures, large lakes were proposed to mitigate seasonal climate changes. To replicate this case, a lake was inserted into North America and a climate model was run using varying carbon dioxide levels. The model runs concluded that while the lake did reduce the seasonality of the region greater than just an increase in carbon dioxide, the addition of a large lake was unable to reduce the seasonality to the levels shown by the floral and faunal data. Ocean heat transport The transport of heat from the tropics to the poles, much like how ocean heat transport functions in modern times, was considered a possibility for the increased temperature and reduced seasonality for the poles. With the increased sea surface temperatures and the increased temperature of the deep ocean water during the early Eocene, one common hypothesis was that due to these increases there would be a greater transport of heat from the tropics to the poles. Simulating these differences, the models produced lower heat transport due to the lower temperature gradients and were unsuccessful in producing an equable climate from only ocean heat transport. Orbital parameters While typically seen as a control on ice growth and seasonality, the orbital parameters were theorized as a possible control on continental temperatures and seasonality. Simulating the Eocene by using an ice free planet, eccentricity, obliquity, and precession were modified in different model runs to determine all the possible different scenarios that could occur and their effects on temperature. One particular case led to warmer winters and cooler summer by up to 30% in the North American continent, and it reduced the seasonal variation of temperature by up to 75%. While orbital parameters did not produce the warming at the poles, the parameters did show a great effect on seasonality and needed to be considered. Polar stratospheric clouds Another method considered for producing the warm polar temperatures were polar stratospheric clouds. Polar stratospheric clouds are clouds that occur in the lower stratosphere at very low temperatures. Polar stratospheric clouds have a great impact on radiative forcing. Due to their minimal albedo properties and their optical thickness, polar stratospheric clouds act similar to a greenhouse gas and traps outgoing longwave radiation. Different types of polar stratospheric clouds occur in the atmosphere: polar stratospheric clouds that are created due to interactions with nitric or sulfuric acid and water (Type I) or polar stratospheric clouds that are created with only water ice (Type II).Methane is an important factor in the creation of the primary Type II polar stratospheric clouds that were created in the early Eocene. Since water vapor is the only supporting substance used in Type II polar stratospheric clouds, the presence of water vapor in the lower stratosphere is necessary where in most situations the presence of water vapor in the lower stratosphere is rare. When methane is oxidized, a significant amount of water vapor is released. Another requirement for polar stratospheric clouds is cold temperatures to ensure condensation and cloud production. Polar stratospheric cloud production, since it requires the cold temperatures, is usually limited to nighttime and winter conditions. With this combination of wetter and colder conditions in the lower stratosphere, polar stratospheric clouds could have formed over wide areas in Polar Regions.To test the polar stratospheric clouds effects on the Eocene climate, models were run comparing the effects of polar stratospheric clouds at the poles to an increase in atmospheric carbon dioxide. The polar stratospheric clouds had a warming effect on the poles, increasing temperatures by up to 20 °C in the winter months. A multitude of feedbacks also occurred in the models due to the polar stratospheric clouds' presence. Any ice growth was slowed immensely and would lead to any present ice melting. Only the poles were affected with the change in temperature and the tropics were unaffected, which with an increase in atmospheric carbon dioxide would also cause the tropics to increase in temperature. Due to the warming of the troposphere from the increased greenhouse effect of the polar stratospheric clouds, the stratosphere would cool and would potentially increase the amount of polar stratospheric clouds. While the polar stratospheric clouds could explain the reduction of the equator to pole temperature gradient and the increased temperatures at the poles during the early Eocene, there are a few drawbacks to maintaining polar stratospheric clouds for an extended period of time. Separate model runs were used to determine the sustainability of the polar stratospheric clouds. It was determined that in order to maintain the lower stratospheric water vapor, methane would need to be continually released and sustained. In addition, the amounts of ice and condensation nuclei would need to be high in order for the polar stratospheric cloud to sustain itself and eventually expand. Middle Eocene The Eocene is not only known for containing the warmest period during the Cenozoic; it also marked the decline into an icehouse climate and the rapid expansion of the Antarctic ice sheet. The transition from a warming climate into a cooling climate began at around 49 Ma. Isotopes of carbon and oxygen indicate a shift to a global cooling climate. The cause of the cooling has been attributed to a significant decrease of >2,000 ppm in atmospheric carbon dioxide concentrations. One proposed cause of the reduction in carbon dioxide during the warming to cooling transition was the azolla event. With the equable climate during the early Eocene, warm temperatures in the arctic allowed for the growth of azolla, which is a floating aquatic fern, on the Arctic Ocean. The significantly high amounts of carbon dioxide also acted to facilitate azolla blooms across the Arctic Ocean. Compared to current carbon dioxide levels, these azolla grew rapidly in the enhanced carbon dioxide levels found in the early Eocene. The isolation of the Arctic Ocean, evidenced by euxinia that occurred at this time, led to stagnant waters and as the azolla sank to the sea floor, they became part of the sediments on the seabed and effectively sequestered the carbon by locking it out of the atmosphere for good. The ability for the azolla to sequester carbon is exceptional, and the enhanced burial of azolla could have had a significant effect on the world atmospheric carbon content and may have been the event to begin the transition into an ice house climate. The azolla event could have led to a draw down of atmospheric carbon dioxide of up to 470 ppm. Assuming the carbon dioxide concentrations were at 900 ppmv prior to the Azolla Event they would have dropped to 430 ppmv, or 30 ppmv more than they are today, after the Azolla Event. This cooling trend at the end of the Early Eocene Climatic Optimum has also been proposed to have been caused by increased siliceous plankton productivity and marine carbon burial, which also helped draw carbon dioxide out of the atmosphere. Cooling after this event continued due to continual decrease in atmospheric carbon dioxide from organic productivity and weathering from mountain building.Global cooling continued until there was a major reversal from cooling to warming in the Bartonian. This warming event, signifying a sudden and temporary reversal of the cooling conditions, is known as the Middle Eocene Climatic Optimum (MECO). At around 41.5 Ma, stable isotopic analysis of samples from Southern Ocean drilling sites indicated a warming event for 600,000 years. A similar shift in carbon isotopes is known from the Northern Hemisphere in the Scaglia Limestones of Italy. Oxygen isotope analysis showed a large negative change in the proportion of heavier oxygen isotopes to lighter oxygen isotopes, which indicates an increase in global temperatures. The warming is considered to be primarily due to carbon dioxide increases, because carbon isotope signatures rule out major methane release during this short-term warming. A sharp increase in atmospheric carbon dioxide was observed with a maximum of 4,000 ppm: the highest amount of atmospheric carbon dioxide detected during the Eocene. Other studies suggest a more modest rise in carbon dioxide levels. The increase in atmospheric carbon dioxide has also been hypothesised to have been driven by increased seafloor spreading rates and metamorphic decarbonation reactions between Australia and Antarctica and increased amounts of volcanism in the region. One possible cause of atmospheric carbon dioxide increase could have been a sudden increase due to metamorphic release due to continental drift and collision of India with Asia and the resulting formation of the Himalayas; however, data on the exact timing of metamorphic release of atmospheric carbon dioxide is not well resolved in the data. Recent studies have mentioned, however, that the removal of the ocean between Asia and India could have released significant amounts of carbon dioxide. Another hypothesis still implicates a diminished negative feedback of silicate weathering as a result of continental rocks having become less weatherable during the warm Early and Middle Eocene, allowing volcanically released carbon dioxide to persist in the atmosphere for longer. Yet another explanation hypothesises that MECO warming was caused by the simultaneous occurrence of minima in both the 400 kyr and 2.4 Myr eccentricity cycles. During the MECO, sea surface temperatures in the Tethys Ocean jumped to 32-36 °C, and Tethyan seawater became more dysoxic. A decline in carbonate accumulation at ocean depths of greater than three kilometres took place synchronously with the peak of the MECO, signifying ocean acidification took place in the deep ocean. An abrupt decrease in lakewater salinity in western North America occurred during this warming interval. This warming is short lived, as benthic oxygen isotope records indicate a return to cooling at ~40 Ma. Late Eocene At the end of the Middle Eocene Climatic Optimum, cooling and the carbon dioxide drawdown continued through the late Eocene and into the Eocene–Oligocene transition around 34 Ma. The post-MECO cooling brought with it a major aridification trend in Asia. The cooling during the initial stages of the opening of the Drake Passage ~38.5 Ma was not global, as evidenced by an absence of cooling in the North Atlantic. During the cooling period, benthic oxygen isotopes show the possibility of ice creation and ice increase during this later cooling. The end of the Eocene and beginning of the Oligocene is marked with the massive expansion of area of the Antarctic ice sheet that was a major step into the icehouse climate. Multiple proxies, such as oxygen isotopes and alkenones, indicate that at the Eocene–Oligocene transition, the atmospheric carbon dioxide concentration had decreased to around 750–800 ppm, approximately twice that of present levels. Along with the decrease of atmospheric carbon dioxide reducing the global temperature, orbital factors in ice creation can be seen with 100,000-year and 400,000-year fluctuations in benthic oxygen isotope records. Another major contribution to the expansion of the ice sheet was the creation of the Antarctic Circumpolar Current. The creation of the Antarctic circumpolar current would isolate the cold water around the Antarctic, which would reduce heat transport to the Antarctic along with creating ocean gyres that result in the upwelling of colder bottom waters. The issue with this hypothesis of the consideration of this being a factor for the Eocene-Oligocene transition is the timing of the creation of the circulation is uncertain. For Drake Passage, sediments indicate the opening occurred ~41 Ma while tectonics indicate that this occurred ~32 Ma. Flora During the early-middle Eocene, forests covered most of the Earth including the poles. Tropical forests extended across much of modern Africa, South America, Central America, India, South-east Asia and China. Paratropical forests grew over North America, Europe and Russia, with broad-leafed evergreen and broad-leafed deciduous forests at higher latitudes.Polar forests were quite extensive. Fossils and even preserved remains of trees such as swamp cypress and dawn redwood from the Eocene have been found on Ellesmere Island in the Arctic. Even at that time, Ellesmere Island was only a few degrees in latitude further south than it is today. Fossils of subtropical and even tropical trees and plants from the Eocene also have been found in Greenland and Alaska. Tropical rainforests grew as far north as northern North America and Europe.Palm trees were growing as far north as Alaska and northern Europe during the early Eocene, although they became less abundant as the climate cooled. Dawn redwoods were far more extensive as well.The earliest definitive Eucalyptus fossils were dated from 51.9 Mya, and were found in the Laguna del Hunco deposit in Chubut province in Argentina.Cooling began mid-period, and by the end of the Eocene continental interiors had begun to dry, with forests thinning considerably in some areas. The newly evolved grasses were still confined to river banks and lake shores, and had not yet expanded into plains and savannas.The cooling also brought seasonal changes. Deciduous trees, better able to cope with large temperature changes, began to overtake evergreen tropical species. By the end of the period, deciduous forests covered large parts of the northern continents, including North America, Eurasia and the Arctic, and rainforests held on only in equatorial South America, Africa, India and Australia.Antarctica began the Eocene fringed with a warm temperate to sub-tropical rainforest. Pollen found in Prydz Bay from the Eocene suggest taiga forest existed there. It became much colder as the period progressed; the heat-loving tropical flora was wiped out, and by the beginning of the Oligocene, the continent hosted deciduous forests and vast stretches of tundra. Fauna During the Eocene, plants and marine faunas became quite modern. Many modern bird orders first appeared in the Eocene. The Eocene oceans were warm and teeming with fish and other sea life. Mammals The oldest known fossils of most of the modern mammal orders appear within a brief period during the early Eocene. At the beginning of the Eocene, several new mammal groups arrived in North America. These modern mammals, like artiodactyls, perissodactyls, and primates, had features like long, thin legs, feet, and hands capable of grasping, as well as differentiated teeth adapted for chewing. Dwarf forms reigned. All the members of the new mammal orders were small, under 10 kg; based on comparisons of tooth size, Eocene mammals were only 60% of the size of the primitive Palaeocene mammals that preceded them. They were also smaller than the mammals that followed them. It is assumed that the hot Eocene temperatures favored smaller animals that were better able to manage the heat.Both groups of modern ungulates (hoofed animals) became prevalent because of a major radiation between Europe and North America, along with carnivorous ungulates like Mesonyx. Early forms of many other modern mammalian orders appeared, including horses (most notably the Eohippus), bats, proboscidians (elephants), primates, rodents, and marsupials. Older primitive forms of mammals declined in variety and importance. Important Eocene land fauna fossil remains have been found in western North America, Europe, Patagonia, Egypt, and southeast Asia. Marine fauna are best known from South Asia and the southeast United States.Established megafauna of the Eocene include the Uintatherium, Arsinoitherium, and brontotheres, in which the former two, unlike the latter, did not belong to ungulates but groups that became extinct shortly after their establishments. Large terrestrial mammalian predators began to take form as the terrestrial carnivores like the Hyaenodon and Daphoenus (the earliest lineage of a once-successful predatory family known as bear dogs). Entelodonts meanwhile established themselves as some of the largest omnivores. The first nimravids, including Dinictis, established themselves as amongst the first feliforms to appear. Their groups became highly successful and continued to live past the Eocene. Basilosaurus is a very well-known Eocene whale, but whales as a group had become very diverse during the Eocene, which is when the major transitions from being terrestrial to fully aquatic in cetaceans occurred. The first sirenians were evolving at this time, and would eventually evolve into the extant manatees and dugongs. It is thought that millions of years after the Cretaceous-Paleogene extinction event, brain sizes of mammals now started to increase, "likely driven by a need for greater cognition in increasingly complex environments". Birds Eocene birds include some enigmatic groups with resemblances to modern forms, some of which continued from the Paleocene. Bird taxa of the Eocene include carnivorous psittaciforms, such as Messelasturidae, Halcyornithidae, large flightless forms such as Gastornis and Eleutherornis, long legged falcon Masillaraptor, ancient galliforms such as Gallinuloides, putative rail relatives of the family Songziidae, various pseudotooth birds such as Gigantornis, the ibis relative Rhynchaeites, primitive swifts of the genus Aegialornis, and primitive penguins such as Archaeospheniscus and Inkayacu. Reptiles Reptile fossils from this time, such as fossils of pythons and turtles, are abundant. Insects and arachnids Several rich fossil insect faunas are known from the Eocene, notably the Baltic amber found mainly along the south coast of the Baltic Sea, amber from the Paris Basin, France, the Fur Formation, Denmark, and the Bembridge Marls from the Isle of Wight, England. Insects found in Eocene deposits mostly belong to genera that exist today, though their range has often shifted since the Eocene. For instance the bibionid genus Plecia is common in fossil faunas from presently temperate areas, but only lives in the tropics and subtropics today. Gallery See also Bolca in Italy List of fossil sites (with link directory) London Clay Messel pit in Germany Wadi El Hitan in Egypt Notes References Further reading Ogg, Jim; June, 2004, Overview of Global Boundary Stratotype Sections and Points (GSSP's) Global Stratotype Sections and Points Accessed April 30, 2006. Stanley, Steven M. Earth System History. New York: W.H. Freeman and Company, 1999. ISBN 0-7167-2882-6 External links PaleoMap Project Paleos Eocene page PBS Deep Time: Eocene Eocene and Oligocene Fossils The UPenn Fossil Forest Project, focusing on the Eocene polar forests in Ellesmere Island, Canada Basilosaurus Primitive Eocene Whales Basilosaurus - The plesiosaur that wasn't.... Detailed maps of Tertiary Western North America Map of Eocene Earth Eocene Microfossils: 60+ images of Foraminifera Eocene Epoch. (2011). In Encyclopædia Britannica. Retrieved from Eocene Epoch \| geochronology	NE.se ID	{ "answer_start": [ 417 ], "text": [ "eocen" ] }
The Eocene (IPA: EE-ə-seen, EE-oh-) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name Eocene comes from the Ancient Greek ἠώς (ēṓs, "dawn") and καινός (kainós, "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the Grande Coupure (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the epoch are well identified, though their exact dates are slightly uncertain. Etymology The term "Eocene" is derived from Ancient Greek ἠώς eos meaning "dawn", and καινός kainos meaning "new" or "recent", as the epoch saw the dawn of recent, or modern, life. Scottish geologist Charles Lyell (ignoring the Quaternary) had divided the Tertiary Epoch into the Eocene, Miocene, Pliocene, and New Pliocene (Holocene) Periods in 1833. British geologist John Phillips had proposed the Cenozoic in 1840 in place of the Tertiary, and Austrian paleontologist Moritz Hörnes had introduced the Paleogene for the Eocene and Neogene for the Miocene and Pliocene in 1853. After decades of inconsistent usage, the newly formed International Commission on Stratigraphy (ICS), in 1969, standardized stratigraphy based on the prevailing opinions in Europe: the Cenozoic Era subdivided into the Tertiary and Quaternary sub-eras, and the Tertiary subdivided into the Paleogene and Neogene periods. In 1978, the Paleogene was officially defined as the Paleocene, Eocene, and Oligocene epochs; and the Neogene as the Miocene and Pliocene epochs. In 1989, Tertiary and Quaternary were removed from the time scale due to the arbitrary nature of their boundary, but Quaternary was reinstated in 2009. Geology Boundaries The beginning of the Eocene is marked by the Paleocene–Eocene Thermal Maximum, a short period of intense warming and ocean acidification brought about by the release of carbon en masse into the atmosphere and ocean systems, which led to a mass extinction of 30–50% of benthic foraminifera–single-celled species which are used as bioindicators of the health of a marine ecosystem—one of the largest in the Cenozoic. This event happened around 55.8 mya, and was one of the most significant periods of global change during the Cenozoic.The end of the Eocene was marked by the Eocene–Oligocene extinction event, also known as the Grande Coupure. Stratigraphy The Eocene is conventionally divided into early (56–47.8 Ma), middle (47.8–38 Ma), and late (38–33.9 Ma) subdivisions. The corresponding rocks are referred to as lower, middle, and upper Eocene. The Ypresian Stage constitutes the lower, the Priabonian Stage the upper; and the Lutetian and Bartonian stages are united as the middle Eocene. Palaeogeography and tectonics During the Eocene, the continents continued to drift toward their present positions. At the beginning of the period, Australia and Antarctica remained connected, and warm equatorial currents may have mixed with colder Antarctic waters, distributing the heat around the planet and keeping global temperatures high. When Australia split from the southern continent around 45 Ma, the warm equatorial currents were routed away from Antarctica. An isolated cold water channel developed between the two continents. However, modeling results call into question the thermal isolation model for late Eocene cooling, and decreasing carbon dioxide levels in the atmosphere may have been more important. Once the Antarctic region began to cool down, the ocean surrounding Antarctica began to freeze, sending cold water and icefloes north and reinforcing the cooling.The northern supercontinent of Laurasia began to fragment, as Europe, Greenland and North America drifted apart.In western North America, the Laramide Orogeny came to an end in the Eocene, and compression was replaced with crustal extension that ultimately gave rise to the Basin and Range Province. Huge lakes formed in the high flat basins among uplifts, resulting in the deposition of the Green River Formation lagerstätte.At about 35 Ma, an asteroid impact on the eastern coast of North America formed the Chesapeake Bay impact crater.In Europe, the Tethys Sea finally disappeared, while the uplift of the Alps isolated its final remnant, the Mediterranean, and created another shallow sea with island archipelagos to the north. Though the North Atlantic was opening, a land connection appears to have remained between North America and Europe since the faunas of the two regions are very similar.Eurasia was separated in three different landmasses 50 Ma; Western Europe, Balkanatolia and Asia. About 40 Ma, Balkanatolia and Asia were connected, while Europe was connected 34 Ma.India collided with Asia, folding to initiate formation of the Himalayas. India collided with the Kohistan–Ladakh Arc around 50.2 Ma and with Karakoram around 40.4 Ma, with the final collision between Asia and India occurring ~40 Ma. Climate The Eocene Epoch contained a wide variety of different climate conditions that includes the warmest climate in the Cenozoic Era, and arguably the warmest time interval since the Permian-Triassic mass extinction and Early Triassic, and ends in an icehouse climate. The evolution of the Eocene climate began with warming after the end of the Paleocene–Eocene Thermal Maximum (PETM) at 56 Ma to a maximum during the Eocene Optimum at around 49 Ma. Recent study show elevation-dependent temperature changes during the Eocene hothouse. During this period of time, little to no ice was present on Earth with a smaller difference in temperature from the equator to the poles. Because of this the maximum sea level was 150 meters higher than current levels. Following the maximum was a descent into an icehouse climate from the Eocene Optimum to the Eocene-Oligocene transition at 34 Ma. During this decrease, ice began to reappear at the poles, and the Eocene-Oligocene transition is the period of time where the Antarctic ice sheet began to rapidly expand. Early Eocene Greenhouse gases, in particular carbon dioxide and methane, played a significant role during the Eocene in controlling the surface temperature. The end of the PETM was met with very large sequestration of carbon dioxide into the forms of methane clathrate, coal, and crude oil at the bottom of the Arctic Ocean, that reduced the atmospheric carbon dioxide. This event was similar in magnitude to the massive release of greenhouse gasses at the beginning of the PETM, and it is hypothesized that the sequestration was mainly due to organic carbon burial and weathering of silicates. For the early Eocene there is much discussion on how much carbon dioxide was in the atmosphere. This is due to numerous proxies representing different atmospheric carbon dioxide content. For example, diverse geochemical and paleontological proxies indicate that at the maximum of global warmth the atmospheric carbon dioxide values were at 700–900 ppm while other proxies such as pedogenic (soil building) carbonate and marine boron isotopes indicate large changes of carbon dioxide of over 2,000 ppm over periods of time of less than 1 million years. Sources for this large influx of carbon dioxide could be attributed to volcanic out-gassing due to North Atlantic rifting or oxidation of methane stored in large reservoirs deposited from the PETM event in the sea floor or wetland environments. For contrast, today the carbon dioxide levels are at 400 ppm or 0.04%. At about the beginning of the Eocene Epoch (55.8–33.9 Ma) the amount of oxygen in the earth's atmosphere more or less doubled.During the early Eocene, methane was another greenhouse gas that had a drastic effect on the climate. The warming effect of one ton of methane dimensions unspecified is approximately 30 times the warming effect of one ton of carbon on a 100-year scale (i.e., methane has a global warming potential of 29.8±11). Most of the methane released to the atmosphere during this period of time would have been from wetlands, swamps, and forests. The atmospheric methane concentration today is 0.000179% or 1.79 ppmv. As a result of the warmer climate and the sea level rise associated with the early Eocene, more wetlands, more forests, and more coal deposits would have been available for methane release. If we compare the early Eocene production of methane to current levels of atmospheric methane, the early Eocene would have produced triple the amount of methane. The warm temperatures during the early Eocene could have increased methane production rates, and methane that is released into the atmosphere would in turn warm the troposphere, cool the stratosphere, and produce water vapor and carbon dioxide through oxidation. Biogenic production of methane produces carbon dioxide and water vapor along with the methane, as well as yielding infrared radiation. The breakdown of methane in an atmosphere containing oxygen produces carbon monoxide, water vapor and infrared radiation. The carbon monoxide is not stable, so it eventually becomes carbon dioxide and in doing so releases yet more infrared radiation. Water vapor traps more infrared than does carbon dioxide. Hyperthermals through the early Eocene During the warming in the early Eocene between 55 and 52 Ma, there were a series of short-term changes of carbon isotope composition in the ocean. These isotope changes occurred due to the release of carbon from the ocean into the atmosphere that led to a temperature increase of 4–8 °C (7.2–14.4 °F) at the surface of the ocean. These hyperthermals led to increased perturbations in planktonic and benthic foraminifera, with a higher rate of sedimentation as a consequence of the warmer temperatures. Recent analysis of and research into these hyperthermals in the early Eocene has led to hypotheses that the hyperthermals are based on orbital parameters, in particular eccentricity and obliquity. The hyperthermals in the early Eocene, notably the Palaeocene–Eocene Thermal Maximum (PETM), the Eocene Thermal Maximum 2 (ETM2), and the Eocene Thermal Maximum 3 (ETM3), were analyzed and found that orbital control may have had a role in triggering the ETM2 and ETM3. Equable climate problem One of the unique features of the Eocene's climate as mentioned before was the equable and homogeneous climate that existed in the early parts of the Eocene. A multitude of proxies support the presence of a warmer equable climate being present during this period of time. A few of these proxies include the presence of fossils native to warm climates, such as crocodiles, located in the higher latitudes, the presence in the high latitudes of frost-intolerant flora such as palm trees which cannot survive during sustained freezes, and fossils of snakes found in the tropics that would require much higher average temperatures to sustain them. TEX86 BAYSPAR measurements indicate extremely high sea surface temperatures of 40 °C (104 °F) to 45 °C (113 °F) at low latitudes, although clumped isotope analyses point to a maximum low latitude sea surface temperature of 36.3 °C (97.3 °F) ± 1.9 °C (35.4 °F) during the Early Eocene Climatic Optimum. Relative to present-day values, bottom water temperatures are 10 °C (18 °F) higher according to isotope proxies. With these bottom water temperatures, temperatures in areas where deep water forms near the poles are unable to be much cooler than the bottom water temperatures.An issue arises, however, when trying to model the Eocene and reproduce the results that are found with the proxy data. Using all different ranges of greenhouse gasses that occurred during the early Eocene, models were unable to produce the warming that was found at the poles and the reduced seasonality that occurs with winters at the poles being substantially warmer. The models, while accurately predicting the tropics, tend to produce significantly cooler temperatures of up to 20 °C (36 °F) colder than the actual determined temperature at the poles. This error has been classified as the "equable climate problem". To solve this problem, the solution would involve finding a process to warm the poles without warming the tropics. Some hypotheses and tests which attempt to find the process are listed below. Large lakes Due to the nature of water as opposed to land, less temperature variability would be present if a large body of water is also present. In an attempt to try to mitigate the cooling polar temperatures, large lakes were proposed to mitigate seasonal climate changes. To replicate this case, a lake was inserted into North America and a climate model was run using varying carbon dioxide levels. The model runs concluded that while the lake did reduce the seasonality of the region greater than just an increase in carbon dioxide, the addition of a large lake was unable to reduce the seasonality to the levels shown by the floral and faunal data. Ocean heat transport The transport of heat from the tropics to the poles, much like how ocean heat transport functions in modern times, was considered a possibility for the increased temperature and reduced seasonality for the poles. With the increased sea surface temperatures and the increased temperature of the deep ocean water during the early Eocene, one common hypothesis was that due to these increases there would be a greater transport of heat from the tropics to the poles. Simulating these differences, the models produced lower heat transport due to the lower temperature gradients and were unsuccessful in producing an equable climate from only ocean heat transport. Orbital parameters While typically seen as a control on ice growth and seasonality, the orbital parameters were theorized as a possible control on continental temperatures and seasonality. Simulating the Eocene by using an ice free planet, eccentricity, obliquity, and precession were modified in different model runs to determine all the possible different scenarios that could occur and their effects on temperature. One particular case led to warmer winters and cooler summer by up to 30% in the North American continent, and it reduced the seasonal variation of temperature by up to 75%. While orbital parameters did not produce the warming at the poles, the parameters did show a great effect on seasonality and needed to be considered. Polar stratospheric clouds Another method considered for producing the warm polar temperatures were polar stratospheric clouds. Polar stratospheric clouds are clouds that occur in the lower stratosphere at very low temperatures. Polar stratospheric clouds have a great impact on radiative forcing. Due to their minimal albedo properties and their optical thickness, polar stratospheric clouds act similar to a greenhouse gas and traps outgoing longwave radiation. Different types of polar stratospheric clouds occur in the atmosphere: polar stratospheric clouds that are created due to interactions with nitric or sulfuric acid and water (Type I) or polar stratospheric clouds that are created with only water ice (Type II).Methane is an important factor in the creation of the primary Type II polar stratospheric clouds that were created in the early Eocene. Since water vapor is the only supporting substance used in Type II polar stratospheric clouds, the presence of water vapor in the lower stratosphere is necessary where in most situations the presence of water vapor in the lower stratosphere is rare. When methane is oxidized, a significant amount of water vapor is released. Another requirement for polar stratospheric clouds is cold temperatures to ensure condensation and cloud production. Polar stratospheric cloud production, since it requires the cold temperatures, is usually limited to nighttime and winter conditions. With this combination of wetter and colder conditions in the lower stratosphere, polar stratospheric clouds could have formed over wide areas in Polar Regions.To test the polar stratospheric clouds effects on the Eocene climate, models were run comparing the effects of polar stratospheric clouds at the poles to an increase in atmospheric carbon dioxide. The polar stratospheric clouds had a warming effect on the poles, increasing temperatures by up to 20 °C in the winter months. A multitude of feedbacks also occurred in the models due to the polar stratospheric clouds' presence. Any ice growth was slowed immensely and would lead to any present ice melting. Only the poles were affected with the change in temperature and the tropics were unaffected, which with an increase in atmospheric carbon dioxide would also cause the tropics to increase in temperature. Due to the warming of the troposphere from the increased greenhouse effect of the polar stratospheric clouds, the stratosphere would cool and would potentially increase the amount of polar stratospheric clouds. While the polar stratospheric clouds could explain the reduction of the equator to pole temperature gradient and the increased temperatures at the poles during the early Eocene, there are a few drawbacks to maintaining polar stratospheric clouds for an extended period of time. Separate model runs were used to determine the sustainability of the polar stratospheric clouds. It was determined that in order to maintain the lower stratospheric water vapor, methane would need to be continually released and sustained. In addition, the amounts of ice and condensation nuclei would need to be high in order for the polar stratospheric cloud to sustain itself and eventually expand. Middle Eocene The Eocene is not only known for containing the warmest period during the Cenozoic; it also marked the decline into an icehouse climate and the rapid expansion of the Antarctic ice sheet. The transition from a warming climate into a cooling climate began at around 49 Ma. Isotopes of carbon and oxygen indicate a shift to a global cooling climate. The cause of the cooling has been attributed to a significant decrease of >2,000 ppm in atmospheric carbon dioxide concentrations. One proposed cause of the reduction in carbon dioxide during the warming to cooling transition was the azolla event. With the equable climate during the early Eocene, warm temperatures in the arctic allowed for the growth of azolla, which is a floating aquatic fern, on the Arctic Ocean. The significantly high amounts of carbon dioxide also acted to facilitate azolla blooms across the Arctic Ocean. Compared to current carbon dioxide levels, these azolla grew rapidly in the enhanced carbon dioxide levels found in the early Eocene. The isolation of the Arctic Ocean, evidenced by euxinia that occurred at this time, led to stagnant waters and as the azolla sank to the sea floor, they became part of the sediments on the seabed and effectively sequestered the carbon by locking it out of the atmosphere for good. The ability for the azolla to sequester carbon is exceptional, and the enhanced burial of azolla could have had a significant effect on the world atmospheric carbon content and may have been the event to begin the transition into an ice house climate. The azolla event could have led to a draw down of atmospheric carbon dioxide of up to 470 ppm. Assuming the carbon dioxide concentrations were at 900 ppmv prior to the Azolla Event they would have dropped to 430 ppmv, or 30 ppmv more than they are today, after the Azolla Event. This cooling trend at the end of the Early Eocene Climatic Optimum has also been proposed to have been caused by increased siliceous plankton productivity and marine carbon burial, which also helped draw carbon dioxide out of the atmosphere. Cooling after this event continued due to continual decrease in atmospheric carbon dioxide from organic productivity and weathering from mountain building.Global cooling continued until there was a major reversal from cooling to warming in the Bartonian. This warming event, signifying a sudden and temporary reversal of the cooling conditions, is known as the Middle Eocene Climatic Optimum (MECO). At around 41.5 Ma, stable isotopic analysis of samples from Southern Ocean drilling sites indicated a warming event for 600,000 years. A similar shift in carbon isotopes is known from the Northern Hemisphere in the Scaglia Limestones of Italy. Oxygen isotope analysis showed a large negative change in the proportion of heavier oxygen isotopes to lighter oxygen isotopes, which indicates an increase in global temperatures. The warming is considered to be primarily due to carbon dioxide increases, because carbon isotope signatures rule out major methane release during this short-term warming. A sharp increase in atmospheric carbon dioxide was observed with a maximum of 4,000 ppm: the highest amount of atmospheric carbon dioxide detected during the Eocene. Other studies suggest a more modest rise in carbon dioxide levels. The increase in atmospheric carbon dioxide has also been hypothesised to have been driven by increased seafloor spreading rates and metamorphic decarbonation reactions between Australia and Antarctica and increased amounts of volcanism in the region. One possible cause of atmospheric carbon dioxide increase could have been a sudden increase due to metamorphic release due to continental drift and collision of India with Asia and the resulting formation of the Himalayas; however, data on the exact timing of metamorphic release of atmospheric carbon dioxide is not well resolved in the data. Recent studies have mentioned, however, that the removal of the ocean between Asia and India could have released significant amounts of carbon dioxide. Another hypothesis still implicates a diminished negative feedback of silicate weathering as a result of continental rocks having become less weatherable during the warm Early and Middle Eocene, allowing volcanically released carbon dioxide to persist in the atmosphere for longer. Yet another explanation hypothesises that MECO warming was caused by the simultaneous occurrence of minima in both the 400 kyr and 2.4 Myr eccentricity cycles. During the MECO, sea surface temperatures in the Tethys Ocean jumped to 32-36 °C, and Tethyan seawater became more dysoxic. A decline in carbonate accumulation at ocean depths of greater than three kilometres took place synchronously with the peak of the MECO, signifying ocean acidification took place in the deep ocean. An abrupt decrease in lakewater salinity in western North America occurred during this warming interval. This warming is short lived, as benthic oxygen isotope records indicate a return to cooling at ~40 Ma. Late Eocene At the end of the Middle Eocene Climatic Optimum, cooling and the carbon dioxide drawdown continued through the late Eocene and into the Eocene–Oligocene transition around 34 Ma. The post-MECO cooling brought with it a major aridification trend in Asia. The cooling during the initial stages of the opening of the Drake Passage ~38.5 Ma was not global, as evidenced by an absence of cooling in the North Atlantic. During the cooling period, benthic oxygen isotopes show the possibility of ice creation and ice increase during this later cooling. The end of the Eocene and beginning of the Oligocene is marked with the massive expansion of area of the Antarctic ice sheet that was a major step into the icehouse climate. Multiple proxies, such as oxygen isotopes and alkenones, indicate that at the Eocene–Oligocene transition, the atmospheric carbon dioxide concentration had decreased to around 750–800 ppm, approximately twice that of present levels. Along with the decrease of atmospheric carbon dioxide reducing the global temperature, orbital factors in ice creation can be seen with 100,000-year and 400,000-year fluctuations in benthic oxygen isotope records. Another major contribution to the expansion of the ice sheet was the creation of the Antarctic Circumpolar Current. The creation of the Antarctic circumpolar current would isolate the cold water around the Antarctic, which would reduce heat transport to the Antarctic along with creating ocean gyres that result in the upwelling of colder bottom waters. The issue with this hypothesis of the consideration of this being a factor for the Eocene-Oligocene transition is the timing of the creation of the circulation is uncertain. For Drake Passage, sediments indicate the opening occurred ~41 Ma while tectonics indicate that this occurred ~32 Ma. Flora During the early-middle Eocene, forests covered most of the Earth including the poles. Tropical forests extended across much of modern Africa, South America, Central America, India, South-east Asia and China. Paratropical forests grew over North America, Europe and Russia, with broad-leafed evergreen and broad-leafed deciduous forests at higher latitudes.Polar forests were quite extensive. Fossils and even preserved remains of trees such as swamp cypress and dawn redwood from the Eocene have been found on Ellesmere Island in the Arctic. Even at that time, Ellesmere Island was only a few degrees in latitude further south than it is today. Fossils of subtropical and even tropical trees and plants from the Eocene also have been found in Greenland and Alaska. Tropical rainforests grew as far north as northern North America and Europe.Palm trees were growing as far north as Alaska and northern Europe during the early Eocene, although they became less abundant as the climate cooled. Dawn redwoods were far more extensive as well.The earliest definitive Eucalyptus fossils were dated from 51.9 Mya, and were found in the Laguna del Hunco deposit in Chubut province in Argentina.Cooling began mid-period, and by the end of the Eocene continental interiors had begun to dry, with forests thinning considerably in some areas. The newly evolved grasses were still confined to river banks and lake shores, and had not yet expanded into plains and savannas.The cooling also brought seasonal changes. Deciduous trees, better able to cope with large temperature changes, began to overtake evergreen tropical species. By the end of the period, deciduous forests covered large parts of the northern continents, including North America, Eurasia and the Arctic, and rainforests held on only in equatorial South America, Africa, India and Australia.Antarctica began the Eocene fringed with a warm temperate to sub-tropical rainforest. Pollen found in Prydz Bay from the Eocene suggest taiga forest existed there. It became much colder as the period progressed; the heat-loving tropical flora was wiped out, and by the beginning of the Oligocene, the continent hosted deciduous forests and vast stretches of tundra. Fauna During the Eocene, plants and marine faunas became quite modern. Many modern bird orders first appeared in the Eocene. The Eocene oceans were warm and teeming with fish and other sea life. Mammals The oldest known fossils of most of the modern mammal orders appear within a brief period during the early Eocene. At the beginning of the Eocene, several new mammal groups arrived in North America. These modern mammals, like artiodactyls, perissodactyls, and primates, had features like long, thin legs, feet, and hands capable of grasping, as well as differentiated teeth adapted for chewing. Dwarf forms reigned. All the members of the new mammal orders were small, under 10 kg; based on comparisons of tooth size, Eocene mammals were only 60% of the size of the primitive Palaeocene mammals that preceded them. They were also smaller than the mammals that followed them. It is assumed that the hot Eocene temperatures favored smaller animals that were better able to manage the heat.Both groups of modern ungulates (hoofed animals) became prevalent because of a major radiation between Europe and North America, along with carnivorous ungulates like Mesonyx. Early forms of many other modern mammalian orders appeared, including horses (most notably the Eohippus), bats, proboscidians (elephants), primates, rodents, and marsupials. Older primitive forms of mammals declined in variety and importance. Important Eocene land fauna fossil remains have been found in western North America, Europe, Patagonia, Egypt, and southeast Asia. Marine fauna are best known from South Asia and the southeast United States.Established megafauna of the Eocene include the Uintatherium, Arsinoitherium, and brontotheres, in which the former two, unlike the latter, did not belong to ungulates but groups that became extinct shortly after their establishments. Large terrestrial mammalian predators began to take form as the terrestrial carnivores like the Hyaenodon and Daphoenus (the earliest lineage of a once-successful predatory family known as bear dogs). Entelodonts meanwhile established themselves as some of the largest omnivores. The first nimravids, including Dinictis, established themselves as amongst the first feliforms to appear. Their groups became highly successful and continued to live past the Eocene. Basilosaurus is a very well-known Eocene whale, but whales as a group had become very diverse during the Eocene, which is when the major transitions from being terrestrial to fully aquatic in cetaceans occurred. The first sirenians were evolving at this time, and would eventually evolve into the extant manatees and dugongs. It is thought that millions of years after the Cretaceous-Paleogene extinction event, brain sizes of mammals now started to increase, "likely driven by a need for greater cognition in increasingly complex environments". Birds Eocene birds include some enigmatic groups with resemblances to modern forms, some of which continued from the Paleocene. Bird taxa of the Eocene include carnivorous psittaciforms, such as Messelasturidae, Halcyornithidae, large flightless forms such as Gastornis and Eleutherornis, long legged falcon Masillaraptor, ancient galliforms such as Gallinuloides, putative rail relatives of the family Songziidae, various pseudotooth birds such as Gigantornis, the ibis relative Rhynchaeites, primitive swifts of the genus Aegialornis, and primitive penguins such as Archaeospheniscus and Inkayacu. Reptiles Reptile fossils from this time, such as fossils of pythons and turtles, are abundant. Insects and arachnids Several rich fossil insect faunas are known from the Eocene, notably the Baltic amber found mainly along the south coast of the Baltic Sea, amber from the Paris Basin, France, the Fur Formation, Denmark, and the Bembridge Marls from the Isle of Wight, England. Insects found in Eocene deposits mostly belong to genera that exist today, though their range has often shifted since the Eocene. For instance the bibionid genus Plecia is common in fossil faunas from presently temperate areas, but only lives in the tropics and subtropics today. Gallery See also Bolca in Italy List of fossil sites (with link directory) London Clay Messel pit in Germany Wadi El Hitan in Egypt Notes References Further reading Ogg, Jim; June, 2004, Overview of Global Boundary Stratotype Sections and Points (GSSP's) Global Stratotype Sections and Points Accessed April 30, 2006. Stanley, Steven M. Earth System History. New York: W.H. Freeman and Company, 1999. ISBN 0-7167-2882-6 External links PaleoMap Project Paleos Eocene page PBS Deep Time: Eocene Eocene and Oligocene Fossils The UPenn Fossil Forest Project, focusing on the Eocene polar forests in Ellesmere Island, Canada Basilosaurus Primitive Eocene Whales Basilosaurus - The plesiosaur that wasn't.... Detailed maps of Tertiary Western North America Map of Eocene Earth Eocene Microfossils: 60+ images of Foraminifera Eocene Epoch. (2011). In Encyclopædia Britannica. Retrieved from Eocene Epoch \| geochronology	Quora topic ID	{ "answer_start": [ 4 ], "text": [ "Eocene" ] }
The Eocene (IPA: EE-ə-seen, EE-oh-) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name Eocene comes from the Ancient Greek ἠώς (ēṓs, "dawn") and καινός (kainós, "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the Grande Coupure (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the epoch are well identified, though their exact dates are slightly uncertain. Etymology The term "Eocene" is derived from Ancient Greek ἠώς eos meaning "dawn", and καινός kainos meaning "new" or "recent", as the epoch saw the dawn of recent, or modern, life. Scottish geologist Charles Lyell (ignoring the Quaternary) had divided the Tertiary Epoch into the Eocene, Miocene, Pliocene, and New Pliocene (Holocene) Periods in 1833. British geologist John Phillips had proposed the Cenozoic in 1840 in place of the Tertiary, and Austrian paleontologist Moritz Hörnes had introduced the Paleogene for the Eocene and Neogene for the Miocene and Pliocene in 1853. After decades of inconsistent usage, the newly formed International Commission on Stratigraphy (ICS), in 1969, standardized stratigraphy based on the prevailing opinions in Europe: the Cenozoic Era subdivided into the Tertiary and Quaternary sub-eras, and the Tertiary subdivided into the Paleogene and Neogene periods. In 1978, the Paleogene was officially defined as the Paleocene, Eocene, and Oligocene epochs; and the Neogene as the Miocene and Pliocene epochs. In 1989, Tertiary and Quaternary were removed from the time scale due to the arbitrary nature of their boundary, but Quaternary was reinstated in 2009. Geology Boundaries The beginning of the Eocene is marked by the Paleocene–Eocene Thermal Maximum, a short period of intense warming and ocean acidification brought about by the release of carbon en masse into the atmosphere and ocean systems, which led to a mass extinction of 30–50% of benthic foraminifera–single-celled species which are used as bioindicators of the health of a marine ecosystem—one of the largest in the Cenozoic. This event happened around 55.8 mya, and was one of the most significant periods of global change during the Cenozoic.The end of the Eocene was marked by the Eocene–Oligocene extinction event, also known as the Grande Coupure. Stratigraphy The Eocene is conventionally divided into early (56–47.8 Ma), middle (47.8–38 Ma), and late (38–33.9 Ma) subdivisions. The corresponding rocks are referred to as lower, middle, and upper Eocene. The Ypresian Stage constitutes the lower, the Priabonian Stage the upper; and the Lutetian and Bartonian stages are united as the middle Eocene. Palaeogeography and tectonics During the Eocene, the continents continued to drift toward their present positions. At the beginning of the period, Australia and Antarctica remained connected, and warm equatorial currents may have mixed with colder Antarctic waters, distributing the heat around the planet and keeping global temperatures high. When Australia split from the southern continent around 45 Ma, the warm equatorial currents were routed away from Antarctica. An isolated cold water channel developed between the two continents. However, modeling results call into question the thermal isolation model for late Eocene cooling, and decreasing carbon dioxide levels in the atmosphere may have been more important. Once the Antarctic region began to cool down, the ocean surrounding Antarctica began to freeze, sending cold water and icefloes north and reinforcing the cooling.The northern supercontinent of Laurasia began to fragment, as Europe, Greenland and North America drifted apart.In western North America, the Laramide Orogeny came to an end in the Eocene, and compression was replaced with crustal extension that ultimately gave rise to the Basin and Range Province. Huge lakes formed in the high flat basins among uplifts, resulting in the deposition of the Green River Formation lagerstätte.At about 35 Ma, an asteroid impact on the eastern coast of North America formed the Chesapeake Bay impact crater.In Europe, the Tethys Sea finally disappeared, while the uplift of the Alps isolated its final remnant, the Mediterranean, and created another shallow sea with island archipelagos to the north. Though the North Atlantic was opening, a land connection appears to have remained between North America and Europe since the faunas of the two regions are very similar.Eurasia was separated in three different landmasses 50 Ma; Western Europe, Balkanatolia and Asia. About 40 Ma, Balkanatolia and Asia were connected, while Europe was connected 34 Ma.India collided with Asia, folding to initiate formation of the Himalayas. India collided with the Kohistan–Ladakh Arc around 50.2 Ma and with Karakoram around 40.4 Ma, with the final collision between Asia and India occurring ~40 Ma. Climate The Eocene Epoch contained a wide variety of different climate conditions that includes the warmest climate in the Cenozoic Era, and arguably the warmest time interval since the Permian-Triassic mass extinction and Early Triassic, and ends in an icehouse climate. The evolution of the Eocene climate began with warming after the end of the Paleocene–Eocene Thermal Maximum (PETM) at 56 Ma to a maximum during the Eocene Optimum at around 49 Ma. Recent study show elevation-dependent temperature changes during the Eocene hothouse. During this period of time, little to no ice was present on Earth with a smaller difference in temperature from the equator to the poles. Because of this the maximum sea level was 150 meters higher than current levels. Following the maximum was a descent into an icehouse climate from the Eocene Optimum to the Eocene-Oligocene transition at 34 Ma. During this decrease, ice began to reappear at the poles, and the Eocene-Oligocene transition is the period of time where the Antarctic ice sheet began to rapidly expand. Early Eocene Greenhouse gases, in particular carbon dioxide and methane, played a significant role during the Eocene in controlling the surface temperature. The end of the PETM was met with very large sequestration of carbon dioxide into the forms of methane clathrate, coal, and crude oil at the bottom of the Arctic Ocean, that reduced the atmospheric carbon dioxide. This event was similar in magnitude to the massive release of greenhouse gasses at the beginning of the PETM, and it is hypothesized that the sequestration was mainly due to organic carbon burial and weathering of silicates. For the early Eocene there is much discussion on how much carbon dioxide was in the atmosphere. This is due to numerous proxies representing different atmospheric carbon dioxide content. For example, diverse geochemical and paleontological proxies indicate that at the maximum of global warmth the atmospheric carbon dioxide values were at 700–900 ppm while other proxies such as pedogenic (soil building) carbonate and marine boron isotopes indicate large changes of carbon dioxide of over 2,000 ppm over periods of time of less than 1 million years. Sources for this large influx of carbon dioxide could be attributed to volcanic out-gassing due to North Atlantic rifting or oxidation of methane stored in large reservoirs deposited from the PETM event in the sea floor or wetland environments. For contrast, today the carbon dioxide levels are at 400 ppm or 0.04%. At about the beginning of the Eocene Epoch (55.8–33.9 Ma) the amount of oxygen in the earth's atmosphere more or less doubled.During the early Eocene, methane was another greenhouse gas that had a drastic effect on the climate. The warming effect of one ton of methane dimensions unspecified is approximately 30 times the warming effect of one ton of carbon on a 100-year scale (i.e., methane has a global warming potential of 29.8±11). Most of the methane released to the atmosphere during this period of time would have been from wetlands, swamps, and forests. The atmospheric methane concentration today is 0.000179% or 1.79 ppmv. As a result of the warmer climate and the sea level rise associated with the early Eocene, more wetlands, more forests, and more coal deposits would have been available for methane release. If we compare the early Eocene production of methane to current levels of atmospheric methane, the early Eocene would have produced triple the amount of methane. The warm temperatures during the early Eocene could have increased methane production rates, and methane that is released into the atmosphere would in turn warm the troposphere, cool the stratosphere, and produce water vapor and carbon dioxide through oxidation. Biogenic production of methane produces carbon dioxide and water vapor along with the methane, as well as yielding infrared radiation. The breakdown of methane in an atmosphere containing oxygen produces carbon monoxide, water vapor and infrared radiation. The carbon monoxide is not stable, so it eventually becomes carbon dioxide and in doing so releases yet more infrared radiation. Water vapor traps more infrared than does carbon dioxide. Hyperthermals through the early Eocene During the warming in the early Eocene between 55 and 52 Ma, there were a series of short-term changes of carbon isotope composition in the ocean. These isotope changes occurred due to the release of carbon from the ocean into the atmosphere that led to a temperature increase of 4–8 °C (7.2–14.4 °F) at the surface of the ocean. These hyperthermals led to increased perturbations in planktonic and benthic foraminifera, with a higher rate of sedimentation as a consequence of the warmer temperatures. Recent analysis of and research into these hyperthermals in the early Eocene has led to hypotheses that the hyperthermals are based on orbital parameters, in particular eccentricity and obliquity. The hyperthermals in the early Eocene, notably the Palaeocene–Eocene Thermal Maximum (PETM), the Eocene Thermal Maximum 2 (ETM2), and the Eocene Thermal Maximum 3 (ETM3), were analyzed and found that orbital control may have had a role in triggering the ETM2 and ETM3. Equable climate problem One of the unique features of the Eocene's climate as mentioned before was the equable and homogeneous climate that existed in the early parts of the Eocene. A multitude of proxies support the presence of a warmer equable climate being present during this period of time. A few of these proxies include the presence of fossils native to warm climates, such as crocodiles, located in the higher latitudes, the presence in the high latitudes of frost-intolerant flora such as palm trees which cannot survive during sustained freezes, and fossils of snakes found in the tropics that would require much higher average temperatures to sustain them. TEX86 BAYSPAR measurements indicate extremely high sea surface temperatures of 40 °C (104 °F) to 45 °C (113 °F) at low latitudes, although clumped isotope analyses point to a maximum low latitude sea surface temperature of 36.3 °C (97.3 °F) ± 1.9 °C (35.4 °F) during the Early Eocene Climatic Optimum. Relative to present-day values, bottom water temperatures are 10 °C (18 °F) higher according to isotope proxies. With these bottom water temperatures, temperatures in areas where deep water forms near the poles are unable to be much cooler than the bottom water temperatures.An issue arises, however, when trying to model the Eocene and reproduce the results that are found with the proxy data. Using all different ranges of greenhouse gasses that occurred during the early Eocene, models were unable to produce the warming that was found at the poles and the reduced seasonality that occurs with winters at the poles being substantially warmer. The models, while accurately predicting the tropics, tend to produce significantly cooler temperatures of up to 20 °C (36 °F) colder than the actual determined temperature at the poles. This error has been classified as the "equable climate problem". To solve this problem, the solution would involve finding a process to warm the poles without warming the tropics. Some hypotheses and tests which attempt to find the process are listed below. Large lakes Due to the nature of water as opposed to land, less temperature variability would be present if a large body of water is also present. In an attempt to try to mitigate the cooling polar temperatures, large lakes were proposed to mitigate seasonal climate changes. To replicate this case, a lake was inserted into North America and a climate model was run using varying carbon dioxide levels. The model runs concluded that while the lake did reduce the seasonality of the region greater than just an increase in carbon dioxide, the addition of a large lake was unable to reduce the seasonality to the levels shown by the floral and faunal data. Ocean heat transport The transport of heat from the tropics to the poles, much like how ocean heat transport functions in modern times, was considered a possibility for the increased temperature and reduced seasonality for the poles. With the increased sea surface temperatures and the increased temperature of the deep ocean water during the early Eocene, one common hypothesis was that due to these increases there would be a greater transport of heat from the tropics to the poles. Simulating these differences, the models produced lower heat transport due to the lower temperature gradients and were unsuccessful in producing an equable climate from only ocean heat transport. Orbital parameters While typically seen as a control on ice growth and seasonality, the orbital parameters were theorized as a possible control on continental temperatures and seasonality. Simulating the Eocene by using an ice free planet, eccentricity, obliquity, and precession were modified in different model runs to determine all the possible different scenarios that could occur and their effects on temperature. One particular case led to warmer winters and cooler summer by up to 30% in the North American continent, and it reduced the seasonal variation of temperature by up to 75%. While orbital parameters did not produce the warming at the poles, the parameters did show a great effect on seasonality and needed to be considered. Polar stratospheric clouds Another method considered for producing the warm polar temperatures were polar stratospheric clouds. Polar stratospheric clouds are clouds that occur in the lower stratosphere at very low temperatures. Polar stratospheric clouds have a great impact on radiative forcing. Due to their minimal albedo properties and their optical thickness, polar stratospheric clouds act similar to a greenhouse gas and traps outgoing longwave radiation. Different types of polar stratospheric clouds occur in the atmosphere: polar stratospheric clouds that are created due to interactions with nitric or sulfuric acid and water (Type I) or polar stratospheric clouds that are created with only water ice (Type II).Methane is an important factor in the creation of the primary Type II polar stratospheric clouds that were created in the early Eocene. Since water vapor is the only supporting substance used in Type II polar stratospheric clouds, the presence of water vapor in the lower stratosphere is necessary where in most situations the presence of water vapor in the lower stratosphere is rare. When methane is oxidized, a significant amount of water vapor is released. Another requirement for polar stratospheric clouds is cold temperatures to ensure condensation and cloud production. Polar stratospheric cloud production, since it requires the cold temperatures, is usually limited to nighttime and winter conditions. With this combination of wetter and colder conditions in the lower stratosphere, polar stratospheric clouds could have formed over wide areas in Polar Regions.To test the polar stratospheric clouds effects on the Eocene climate, models were run comparing the effects of polar stratospheric clouds at the poles to an increase in atmospheric carbon dioxide. The polar stratospheric clouds had a warming effect on the poles, increasing temperatures by up to 20 °C in the winter months. A multitude of feedbacks also occurred in the models due to the polar stratospheric clouds' presence. Any ice growth was slowed immensely and would lead to any present ice melting. Only the poles were affected with the change in temperature and the tropics were unaffected, which with an increase in atmospheric carbon dioxide would also cause the tropics to increase in temperature. Due to the warming of the troposphere from the increased greenhouse effect of the polar stratospheric clouds, the stratosphere would cool and would potentially increase the amount of polar stratospheric clouds. While the polar stratospheric clouds could explain the reduction of the equator to pole temperature gradient and the increased temperatures at the poles during the early Eocene, there are a few drawbacks to maintaining polar stratospheric clouds for an extended period of time. Separate model runs were used to determine the sustainability of the polar stratospheric clouds. It was determined that in order to maintain the lower stratospheric water vapor, methane would need to be continually released and sustained. In addition, the amounts of ice and condensation nuclei would need to be high in order for the polar stratospheric cloud to sustain itself and eventually expand. Middle Eocene The Eocene is not only known for containing the warmest period during the Cenozoic; it also marked the decline into an icehouse climate and the rapid expansion of the Antarctic ice sheet. The transition from a warming climate into a cooling climate began at around 49 Ma. Isotopes of carbon and oxygen indicate a shift to a global cooling climate. The cause of the cooling has been attributed to a significant decrease of >2,000 ppm in atmospheric carbon dioxide concentrations. One proposed cause of the reduction in carbon dioxide during the warming to cooling transition was the azolla event. With the equable climate during the early Eocene, warm temperatures in the arctic allowed for the growth of azolla, which is a floating aquatic fern, on the Arctic Ocean. The significantly high amounts of carbon dioxide also acted to facilitate azolla blooms across the Arctic Ocean. Compared to current carbon dioxide levels, these azolla grew rapidly in the enhanced carbon dioxide levels found in the early Eocene. The isolation of the Arctic Ocean, evidenced by euxinia that occurred at this time, led to stagnant waters and as the azolla sank to the sea floor, they became part of the sediments on the seabed and effectively sequestered the carbon by locking it out of the atmosphere for good. The ability for the azolla to sequester carbon is exceptional, and the enhanced burial of azolla could have had a significant effect on the world atmospheric carbon content and may have been the event to begin the transition into an ice house climate. The azolla event could have led to a draw down of atmospheric carbon dioxide of up to 470 ppm. Assuming the carbon dioxide concentrations were at 900 ppmv prior to the Azolla Event they would have dropped to 430 ppmv, or 30 ppmv more than they are today, after the Azolla Event. This cooling trend at the end of the Early Eocene Climatic Optimum has also been proposed to have been caused by increased siliceous plankton productivity and marine carbon burial, which also helped draw carbon dioxide out of the atmosphere. Cooling after this event continued due to continual decrease in atmospheric carbon dioxide from organic productivity and weathering from mountain building.Global cooling continued until there was a major reversal from cooling to warming in the Bartonian. This warming event, signifying a sudden and temporary reversal of the cooling conditions, is known as the Middle Eocene Climatic Optimum (MECO). At around 41.5 Ma, stable isotopic analysis of samples from Southern Ocean drilling sites indicated a warming event for 600,000 years. A similar shift in carbon isotopes is known from the Northern Hemisphere in the Scaglia Limestones of Italy. Oxygen isotope analysis showed a large negative change in the proportion of heavier oxygen isotopes to lighter oxygen isotopes, which indicates an increase in global temperatures. The warming is considered to be primarily due to carbon dioxide increases, because carbon isotope signatures rule out major methane release during this short-term warming. A sharp increase in atmospheric carbon dioxide was observed with a maximum of 4,000 ppm: the highest amount of atmospheric carbon dioxide detected during the Eocene. Other studies suggest a more modest rise in carbon dioxide levels. The increase in atmospheric carbon dioxide has also been hypothesised to have been driven by increased seafloor spreading rates and metamorphic decarbonation reactions between Australia and Antarctica and increased amounts of volcanism in the region. One possible cause of atmospheric carbon dioxide increase could have been a sudden increase due to metamorphic release due to continental drift and collision of India with Asia and the resulting formation of the Himalayas; however, data on the exact timing of metamorphic release of atmospheric carbon dioxide is not well resolved in the data. Recent studies have mentioned, however, that the removal of the ocean between Asia and India could have released significant amounts of carbon dioxide. Another hypothesis still implicates a diminished negative feedback of silicate weathering as a result of continental rocks having become less weatherable during the warm Early and Middle Eocene, allowing volcanically released carbon dioxide to persist in the atmosphere for longer. Yet another explanation hypothesises that MECO warming was caused by the simultaneous occurrence of minima in both the 400 kyr and 2.4 Myr eccentricity cycles. During the MECO, sea surface temperatures in the Tethys Ocean jumped to 32-36 °C, and Tethyan seawater became more dysoxic. A decline in carbonate accumulation at ocean depths of greater than three kilometres took place synchronously with the peak of the MECO, signifying ocean acidification took place in the deep ocean. An abrupt decrease in lakewater salinity in western North America occurred during this warming interval. This warming is short lived, as benthic oxygen isotope records indicate a return to cooling at ~40 Ma. Late Eocene At the end of the Middle Eocene Climatic Optimum, cooling and the carbon dioxide drawdown continued through the late Eocene and into the Eocene–Oligocene transition around 34 Ma. The post-MECO cooling brought with it a major aridification trend in Asia. The cooling during the initial stages of the opening of the Drake Passage ~38.5 Ma was not global, as evidenced by an absence of cooling in the North Atlantic. During the cooling period, benthic oxygen isotopes show the possibility of ice creation and ice increase during this later cooling. The end of the Eocene and beginning of the Oligocene is marked with the massive expansion of area of the Antarctic ice sheet that was a major step into the icehouse climate. Multiple proxies, such as oxygen isotopes and alkenones, indicate that at the Eocene–Oligocene transition, the atmospheric carbon dioxide concentration had decreased to around 750–800 ppm, approximately twice that of present levels. Along with the decrease of atmospheric carbon dioxide reducing the global temperature, orbital factors in ice creation can be seen with 100,000-year and 400,000-year fluctuations in benthic oxygen isotope records. Another major contribution to the expansion of the ice sheet was the creation of the Antarctic Circumpolar Current. The creation of the Antarctic circumpolar current would isolate the cold water around the Antarctic, which would reduce heat transport to the Antarctic along with creating ocean gyres that result in the upwelling of colder bottom waters. The issue with this hypothesis of the consideration of this being a factor for the Eocene-Oligocene transition is the timing of the creation of the circulation is uncertain. For Drake Passage, sediments indicate the opening occurred ~41 Ma while tectonics indicate that this occurred ~32 Ma. Flora During the early-middle Eocene, forests covered most of the Earth including the poles. Tropical forests extended across much of modern Africa, South America, Central America, India, South-east Asia and China. Paratropical forests grew over North America, Europe and Russia, with broad-leafed evergreen and broad-leafed deciduous forests at higher latitudes.Polar forests were quite extensive. Fossils and even preserved remains of trees such as swamp cypress and dawn redwood from the Eocene have been found on Ellesmere Island in the Arctic. Even at that time, Ellesmere Island was only a few degrees in latitude further south than it is today. Fossils of subtropical and even tropical trees and plants from the Eocene also have been found in Greenland and Alaska. Tropical rainforests grew as far north as northern North America and Europe.Palm trees were growing as far north as Alaska and northern Europe during the early Eocene, although they became less abundant as the climate cooled. Dawn redwoods were far more extensive as well.The earliest definitive Eucalyptus fossils were dated from 51.9 Mya, and were found in the Laguna del Hunco deposit in Chubut province in Argentina.Cooling began mid-period, and by the end of the Eocene continental interiors had begun to dry, with forests thinning considerably in some areas. The newly evolved grasses were still confined to river banks and lake shores, and had not yet expanded into plains and savannas.The cooling also brought seasonal changes. Deciduous trees, better able to cope with large temperature changes, began to overtake evergreen tropical species. By the end of the period, deciduous forests covered large parts of the northern continents, including North America, Eurasia and the Arctic, and rainforests held on only in equatorial South America, Africa, India and Australia.Antarctica began the Eocene fringed with a warm temperate to sub-tropical rainforest. Pollen found in Prydz Bay from the Eocene suggest taiga forest existed there. It became much colder as the period progressed; the heat-loving tropical flora was wiped out, and by the beginning of the Oligocene, the continent hosted deciduous forests and vast stretches of tundra. Fauna During the Eocene, plants and marine faunas became quite modern. Many modern bird orders first appeared in the Eocene. The Eocene oceans were warm and teeming with fish and other sea life. Mammals The oldest known fossils of most of the modern mammal orders appear within a brief period during the early Eocene. At the beginning of the Eocene, several new mammal groups arrived in North America. These modern mammals, like artiodactyls, perissodactyls, and primates, had features like long, thin legs, feet, and hands capable of grasping, as well as differentiated teeth adapted for chewing. Dwarf forms reigned. All the members of the new mammal orders were small, under 10 kg; based on comparisons of tooth size, Eocene mammals were only 60% of the size of the primitive Palaeocene mammals that preceded them. They were also smaller than the mammals that followed them. It is assumed that the hot Eocene temperatures favored smaller animals that were better able to manage the heat.Both groups of modern ungulates (hoofed animals) became prevalent because of a major radiation between Europe and North America, along with carnivorous ungulates like Mesonyx. Early forms of many other modern mammalian orders appeared, including horses (most notably the Eohippus), bats, proboscidians (elephants), primates, rodents, and marsupials. Older primitive forms of mammals declined in variety and importance. Important Eocene land fauna fossil remains have been found in western North America, Europe, Patagonia, Egypt, and southeast Asia. Marine fauna are best known from South Asia and the southeast United States.Established megafauna of the Eocene include the Uintatherium, Arsinoitherium, and brontotheres, in which the former two, unlike the latter, did not belong to ungulates but groups that became extinct shortly after their establishments. Large terrestrial mammalian predators began to take form as the terrestrial carnivores like the Hyaenodon and Daphoenus (the earliest lineage of a once-successful predatory family known as bear dogs). Entelodonts meanwhile established themselves as some of the largest omnivores. The first nimravids, including Dinictis, established themselves as amongst the first feliforms to appear. Their groups became highly successful and continued to live past the Eocene. Basilosaurus is a very well-known Eocene whale, but whales as a group had become very diverse during the Eocene, which is when the major transitions from being terrestrial to fully aquatic in cetaceans occurred. The first sirenians were evolving at this time, and would eventually evolve into the extant manatees and dugongs. It is thought that millions of years after the Cretaceous-Paleogene extinction event, brain sizes of mammals now started to increase, "likely driven by a need for greater cognition in increasingly complex environments". Birds Eocene birds include some enigmatic groups with resemblances to modern forms, some of which continued from the Paleocene. Bird taxa of the Eocene include carnivorous psittaciforms, such as Messelasturidae, Halcyornithidae, large flightless forms such as Gastornis and Eleutherornis, long legged falcon Masillaraptor, ancient galliforms such as Gallinuloides, putative rail relatives of the family Songziidae, various pseudotooth birds such as Gigantornis, the ibis relative Rhynchaeites, primitive swifts of the genus Aegialornis, and primitive penguins such as Archaeospheniscus and Inkayacu. Reptiles Reptile fossils from this time, such as fossils of pythons and turtles, are abundant. Insects and arachnids Several rich fossil insect faunas are known from the Eocene, notably the Baltic amber found mainly along the south coast of the Baltic Sea, amber from the Paris Basin, France, the Fur Formation, Denmark, and the Bembridge Marls from the Isle of Wight, England. Insects found in Eocene deposits mostly belong to genera that exist today, though their range has often shifted since the Eocene. For instance the bibionid genus Plecia is common in fossil faunas from presently temperate areas, but only lives in the tropics and subtropics today. Gallery See also Bolca in Italy List of fossil sites (with link directory) London Clay Messel pit in Germany Wadi El Hitan in Egypt Notes References Further reading Ogg, Jim; June, 2004, Overview of Global Boundary Stratotype Sections and Points (GSSP's) Global Stratotype Sections and Points Accessed April 30, 2006. Stanley, Steven M. Earth System History. New York: W.H. Freeman and Company, 1999. ISBN 0-7167-2882-6 External links PaleoMap Project Paleos Eocene page PBS Deep Time: Eocene Eocene and Oligocene Fossils The UPenn Fossil Forest Project, focusing on the Eocene polar forests in Ellesmere Island, Canada Basilosaurus Primitive Eocene Whales Basilosaurus - The plesiosaur that wasn't.... Detailed maps of Tertiary Western North America Map of Eocene Earth Eocene Microfossils: 60+ images of Foraminifera Eocene Epoch. (2011). In Encyclopædia Britannica. Retrieved from Eocene Epoch \| geochronology	named by	{ "answer_start": [ 1276 ], "text": [ "Charles Lyell" ] }
The Eocene (IPA: EE-ə-seen, EE-oh-) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name Eocene comes from the Ancient Greek ἠώς (ēṓs, "dawn") and καινός (kainós, "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the Grande Coupure (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the epoch are well identified, though their exact dates are slightly uncertain. Etymology The term "Eocene" is derived from Ancient Greek ἠώς eos meaning "dawn", and καινός kainos meaning "new" or "recent", as the epoch saw the dawn of recent, or modern, life. Scottish geologist Charles Lyell (ignoring the Quaternary) had divided the Tertiary Epoch into the Eocene, Miocene, Pliocene, and New Pliocene (Holocene) Periods in 1833. British geologist John Phillips had proposed the Cenozoic in 1840 in place of the Tertiary, and Austrian paleontologist Moritz Hörnes had introduced the Paleogene for the Eocene and Neogene for the Miocene and Pliocene in 1853. After decades of inconsistent usage, the newly formed International Commission on Stratigraphy (ICS), in 1969, standardized stratigraphy based on the prevailing opinions in Europe: the Cenozoic Era subdivided into the Tertiary and Quaternary sub-eras, and the Tertiary subdivided into the Paleogene and Neogene periods. In 1978, the Paleogene was officially defined as the Paleocene, Eocene, and Oligocene epochs; and the Neogene as the Miocene and Pliocene epochs. In 1989, Tertiary and Quaternary were removed from the time scale due to the arbitrary nature of their boundary, but Quaternary was reinstated in 2009. Geology Boundaries The beginning of the Eocene is marked by the Paleocene–Eocene Thermal Maximum, a short period of intense warming and ocean acidification brought about by the release of carbon en masse into the atmosphere and ocean systems, which led to a mass extinction of 30–50% of benthic foraminifera–single-celled species which are used as bioindicators of the health of a marine ecosystem—one of the largest in the Cenozoic. This event happened around 55.8 mya, and was one of the most significant periods of global change during the Cenozoic.The end of the Eocene was marked by the Eocene–Oligocene extinction event, also known as the Grande Coupure. Stratigraphy The Eocene is conventionally divided into early (56–47.8 Ma), middle (47.8–38 Ma), and late (38–33.9 Ma) subdivisions. The corresponding rocks are referred to as lower, middle, and upper Eocene. The Ypresian Stage constitutes the lower, the Priabonian Stage the upper; and the Lutetian and Bartonian stages are united as the middle Eocene. Palaeogeography and tectonics During the Eocene, the continents continued to drift toward their present positions. At the beginning of the period, Australia and Antarctica remained connected, and warm equatorial currents may have mixed with colder Antarctic waters, distributing the heat around the planet and keeping global temperatures high. When Australia split from the southern continent around 45 Ma, the warm equatorial currents were routed away from Antarctica. An isolated cold water channel developed between the two continents. However, modeling results call into question the thermal isolation model for late Eocene cooling, and decreasing carbon dioxide levels in the atmosphere may have been more important. Once the Antarctic region began to cool down, the ocean surrounding Antarctica began to freeze, sending cold water and icefloes north and reinforcing the cooling.The northern supercontinent of Laurasia began to fragment, as Europe, Greenland and North America drifted apart.In western North America, the Laramide Orogeny came to an end in the Eocene, and compression was replaced with crustal extension that ultimately gave rise to the Basin and Range Province. Huge lakes formed in the high flat basins among uplifts, resulting in the deposition of the Green River Formation lagerstätte.At about 35 Ma, an asteroid impact on the eastern coast of North America formed the Chesapeake Bay impact crater.In Europe, the Tethys Sea finally disappeared, while the uplift of the Alps isolated its final remnant, the Mediterranean, and created another shallow sea with island archipelagos to the north. Though the North Atlantic was opening, a land connection appears to have remained between North America and Europe since the faunas of the two regions are very similar.Eurasia was separated in three different landmasses 50 Ma; Western Europe, Balkanatolia and Asia. About 40 Ma, Balkanatolia and Asia were connected, while Europe was connected 34 Ma.India collided with Asia, folding to initiate formation of the Himalayas. India collided with the Kohistan–Ladakh Arc around 50.2 Ma and with Karakoram around 40.4 Ma, with the final collision between Asia and India occurring ~40 Ma. Climate The Eocene Epoch contained a wide variety of different climate conditions that includes the warmest climate in the Cenozoic Era, and arguably the warmest time interval since the Permian-Triassic mass extinction and Early Triassic, and ends in an icehouse climate. The evolution of the Eocene climate began with warming after the end of the Paleocene–Eocene Thermal Maximum (PETM) at 56 Ma to a maximum during the Eocene Optimum at around 49 Ma. Recent study show elevation-dependent temperature changes during the Eocene hothouse. During this period of time, little to no ice was present on Earth with a smaller difference in temperature from the equator to the poles. Because of this the maximum sea level was 150 meters higher than current levels. Following the maximum was a descent into an icehouse climate from the Eocene Optimum to the Eocene-Oligocene transition at 34 Ma. During this decrease, ice began to reappear at the poles, and the Eocene-Oligocene transition is the period of time where the Antarctic ice sheet began to rapidly expand. Early Eocene Greenhouse gases, in particular carbon dioxide and methane, played a significant role during the Eocene in controlling the surface temperature. The end of the PETM was met with very large sequestration of carbon dioxide into the forms of methane clathrate, coal, and crude oil at the bottom of the Arctic Ocean, that reduced the atmospheric carbon dioxide. This event was similar in magnitude to the massive release of greenhouse gasses at the beginning of the PETM, and it is hypothesized that the sequestration was mainly due to organic carbon burial and weathering of silicates. For the early Eocene there is much discussion on how much carbon dioxide was in the atmosphere. This is due to numerous proxies representing different atmospheric carbon dioxide content. For example, diverse geochemical and paleontological proxies indicate that at the maximum of global warmth the atmospheric carbon dioxide values were at 700–900 ppm while other proxies such as pedogenic (soil building) carbonate and marine boron isotopes indicate large changes of carbon dioxide of over 2,000 ppm over periods of time of less than 1 million years. Sources for this large influx of carbon dioxide could be attributed to volcanic out-gassing due to North Atlantic rifting or oxidation of methane stored in large reservoirs deposited from the PETM event in the sea floor or wetland environments. For contrast, today the carbon dioxide levels are at 400 ppm or 0.04%. At about the beginning of the Eocene Epoch (55.8–33.9 Ma) the amount of oxygen in the earth's atmosphere more or less doubled.During the early Eocene, methane was another greenhouse gas that had a drastic effect on the climate. The warming effect of one ton of methane dimensions unspecified is approximately 30 times the warming effect of one ton of carbon on a 100-year scale (i.e., methane has a global warming potential of 29.8±11). Most of the methane released to the atmosphere during this period of time would have been from wetlands, swamps, and forests. The atmospheric methane concentration today is 0.000179% or 1.79 ppmv. As a result of the warmer climate and the sea level rise associated with the early Eocene, more wetlands, more forests, and more coal deposits would have been available for methane release. If we compare the early Eocene production of methane to current levels of atmospheric methane, the early Eocene would have produced triple the amount of methane. The warm temperatures during the early Eocene could have increased methane production rates, and methane that is released into the atmosphere would in turn warm the troposphere, cool the stratosphere, and produce water vapor and carbon dioxide through oxidation. Biogenic production of methane produces carbon dioxide and water vapor along with the methane, as well as yielding infrared radiation. The breakdown of methane in an atmosphere containing oxygen produces carbon monoxide, water vapor and infrared radiation. The carbon monoxide is not stable, so it eventually becomes carbon dioxide and in doing so releases yet more infrared radiation. Water vapor traps more infrared than does carbon dioxide. Hyperthermals through the early Eocene During the warming in the early Eocene between 55 and 52 Ma, there were a series of short-term changes of carbon isotope composition in the ocean. These isotope changes occurred due to the release of carbon from the ocean into the atmosphere that led to a temperature increase of 4–8 °C (7.2–14.4 °F) at the surface of the ocean. These hyperthermals led to increased perturbations in planktonic and benthic foraminifera, with a higher rate of sedimentation as a consequence of the warmer temperatures. Recent analysis of and research into these hyperthermals in the early Eocene has led to hypotheses that the hyperthermals are based on orbital parameters, in particular eccentricity and obliquity. The hyperthermals in the early Eocene, notably the Palaeocene–Eocene Thermal Maximum (PETM), the Eocene Thermal Maximum 2 (ETM2), and the Eocene Thermal Maximum 3 (ETM3), were analyzed and found that orbital control may have had a role in triggering the ETM2 and ETM3. Equable climate problem One of the unique features of the Eocene's climate as mentioned before was the equable and homogeneous climate that existed in the early parts of the Eocene. A multitude of proxies support the presence of a warmer equable climate being present during this period of time. A few of these proxies include the presence of fossils native to warm climates, such as crocodiles, located in the higher latitudes, the presence in the high latitudes of frost-intolerant flora such as palm trees which cannot survive during sustained freezes, and fossils of snakes found in the tropics that would require much higher average temperatures to sustain them. TEX86 BAYSPAR measurements indicate extremely high sea surface temperatures of 40 °C (104 °F) to 45 °C (113 °F) at low latitudes, although clumped isotope analyses point to a maximum low latitude sea surface temperature of 36.3 °C (97.3 °F) ± 1.9 °C (35.4 °F) during the Early Eocene Climatic Optimum. Relative to present-day values, bottom water temperatures are 10 °C (18 °F) higher according to isotope proxies. With these bottom water temperatures, temperatures in areas where deep water forms near the poles are unable to be much cooler than the bottom water temperatures.An issue arises, however, when trying to model the Eocene and reproduce the results that are found with the proxy data. Using all different ranges of greenhouse gasses that occurred during the early Eocene, models were unable to produce the warming that was found at the poles and the reduced seasonality that occurs with winters at the poles being substantially warmer. The models, while accurately predicting the tropics, tend to produce significantly cooler temperatures of up to 20 °C (36 °F) colder than the actual determined temperature at the poles. This error has been classified as the "equable climate problem". To solve this problem, the solution would involve finding a process to warm the poles without warming the tropics. Some hypotheses and tests which attempt to find the process are listed below. Large lakes Due to the nature of water as opposed to land, less temperature variability would be present if a large body of water is also present. In an attempt to try to mitigate the cooling polar temperatures, large lakes were proposed to mitigate seasonal climate changes. To replicate this case, a lake was inserted into North America and a climate model was run using varying carbon dioxide levels. The model runs concluded that while the lake did reduce the seasonality of the region greater than just an increase in carbon dioxide, the addition of a large lake was unable to reduce the seasonality to the levels shown by the floral and faunal data. Ocean heat transport The transport of heat from the tropics to the poles, much like how ocean heat transport functions in modern times, was considered a possibility for the increased temperature and reduced seasonality for the poles. With the increased sea surface temperatures and the increased temperature of the deep ocean water during the early Eocene, one common hypothesis was that due to these increases there would be a greater transport of heat from the tropics to the poles. Simulating these differences, the models produced lower heat transport due to the lower temperature gradients and were unsuccessful in producing an equable climate from only ocean heat transport. Orbital parameters While typically seen as a control on ice growth and seasonality, the orbital parameters were theorized as a possible control on continental temperatures and seasonality. Simulating the Eocene by using an ice free planet, eccentricity, obliquity, and precession were modified in different model runs to determine all the possible different scenarios that could occur and their effects on temperature. One particular case led to warmer winters and cooler summer by up to 30% in the North American continent, and it reduced the seasonal variation of temperature by up to 75%. While orbital parameters did not produce the warming at the poles, the parameters did show a great effect on seasonality and needed to be considered. Polar stratospheric clouds Another method considered for producing the warm polar temperatures were polar stratospheric clouds. Polar stratospheric clouds are clouds that occur in the lower stratosphere at very low temperatures. Polar stratospheric clouds have a great impact on radiative forcing. Due to their minimal albedo properties and their optical thickness, polar stratospheric clouds act similar to a greenhouse gas and traps outgoing longwave radiation. Different types of polar stratospheric clouds occur in the atmosphere: polar stratospheric clouds that are created due to interactions with nitric or sulfuric acid and water (Type I) or polar stratospheric clouds that are created with only water ice (Type II).Methane is an important factor in the creation of the primary Type II polar stratospheric clouds that were created in the early Eocene. Since water vapor is the only supporting substance used in Type II polar stratospheric clouds, the presence of water vapor in the lower stratosphere is necessary where in most situations the presence of water vapor in the lower stratosphere is rare. When methane is oxidized, a significant amount of water vapor is released. Another requirement for polar stratospheric clouds is cold temperatures to ensure condensation and cloud production. Polar stratospheric cloud production, since it requires the cold temperatures, is usually limited to nighttime and winter conditions. With this combination of wetter and colder conditions in the lower stratosphere, polar stratospheric clouds could have formed over wide areas in Polar Regions.To test the polar stratospheric clouds effects on the Eocene climate, models were run comparing the effects of polar stratospheric clouds at the poles to an increase in atmospheric carbon dioxide. The polar stratospheric clouds had a warming effect on the poles, increasing temperatures by up to 20 °C in the winter months. A multitude of feedbacks also occurred in the models due to the polar stratospheric clouds' presence. Any ice growth was slowed immensely and would lead to any present ice melting. Only the poles were affected with the change in temperature and the tropics were unaffected, which with an increase in atmospheric carbon dioxide would also cause the tropics to increase in temperature. Due to the warming of the troposphere from the increased greenhouse effect of the polar stratospheric clouds, the stratosphere would cool and would potentially increase the amount of polar stratospheric clouds. While the polar stratospheric clouds could explain the reduction of the equator to pole temperature gradient and the increased temperatures at the poles during the early Eocene, there are a few drawbacks to maintaining polar stratospheric clouds for an extended period of time. Separate model runs were used to determine the sustainability of the polar stratospheric clouds. It was determined that in order to maintain the lower stratospheric water vapor, methane would need to be continually released and sustained. In addition, the amounts of ice and condensation nuclei would need to be high in order for the polar stratospheric cloud to sustain itself and eventually expand. Middle Eocene The Eocene is not only known for containing the warmest period during the Cenozoic; it also marked the decline into an icehouse climate and the rapid expansion of the Antarctic ice sheet. The transition from a warming climate into a cooling climate began at around 49 Ma. Isotopes of carbon and oxygen indicate a shift to a global cooling climate. The cause of the cooling has been attributed to a significant decrease of >2,000 ppm in atmospheric carbon dioxide concentrations. One proposed cause of the reduction in carbon dioxide during the warming to cooling transition was the azolla event. With the equable climate during the early Eocene, warm temperatures in the arctic allowed for the growth of azolla, which is a floating aquatic fern, on the Arctic Ocean. The significantly high amounts of carbon dioxide also acted to facilitate azolla blooms across the Arctic Ocean. Compared to current carbon dioxide levels, these azolla grew rapidly in the enhanced carbon dioxide levels found in the early Eocene. The isolation of the Arctic Ocean, evidenced by euxinia that occurred at this time, led to stagnant waters and as the azolla sank to the sea floor, they became part of the sediments on the seabed and effectively sequestered the carbon by locking it out of the atmosphere for good. The ability for the azolla to sequester carbon is exceptional, and the enhanced burial of azolla could have had a significant effect on the world atmospheric carbon content and may have been the event to begin the transition into an ice house climate. The azolla event could have led to a draw down of atmospheric carbon dioxide of up to 470 ppm. Assuming the carbon dioxide concentrations were at 900 ppmv prior to the Azolla Event they would have dropped to 430 ppmv, or 30 ppmv more than they are today, after the Azolla Event. This cooling trend at the end of the Early Eocene Climatic Optimum has also been proposed to have been caused by increased siliceous plankton productivity and marine carbon burial, which also helped draw carbon dioxide out of the atmosphere. Cooling after this event continued due to continual decrease in atmospheric carbon dioxide from organic productivity and weathering from mountain building.Global cooling continued until there was a major reversal from cooling to warming in the Bartonian. This warming event, signifying a sudden and temporary reversal of the cooling conditions, is known as the Middle Eocene Climatic Optimum (MECO). At around 41.5 Ma, stable isotopic analysis of samples from Southern Ocean drilling sites indicated a warming event for 600,000 years. A similar shift in carbon isotopes is known from the Northern Hemisphere in the Scaglia Limestones of Italy. Oxygen isotope analysis showed a large negative change in the proportion of heavier oxygen isotopes to lighter oxygen isotopes, which indicates an increase in global temperatures. The warming is considered to be primarily due to carbon dioxide increases, because carbon isotope signatures rule out major methane release during this short-term warming. A sharp increase in atmospheric carbon dioxide was observed with a maximum of 4,000 ppm: the highest amount of atmospheric carbon dioxide detected during the Eocene. Other studies suggest a more modest rise in carbon dioxide levels. The increase in atmospheric carbon dioxide has also been hypothesised to have been driven by increased seafloor spreading rates and metamorphic decarbonation reactions between Australia and Antarctica and increased amounts of volcanism in the region. One possible cause of atmospheric carbon dioxide increase could have been a sudden increase due to metamorphic release due to continental drift and collision of India with Asia and the resulting formation of the Himalayas; however, data on the exact timing of metamorphic release of atmospheric carbon dioxide is not well resolved in the data. Recent studies have mentioned, however, that the removal of the ocean between Asia and India could have released significant amounts of carbon dioxide. Another hypothesis still implicates a diminished negative feedback of silicate weathering as a result of continental rocks having become less weatherable during the warm Early and Middle Eocene, allowing volcanically released carbon dioxide to persist in the atmosphere for longer. Yet another explanation hypothesises that MECO warming was caused by the simultaneous occurrence of minima in both the 400 kyr and 2.4 Myr eccentricity cycles. During the MECO, sea surface temperatures in the Tethys Ocean jumped to 32-36 °C, and Tethyan seawater became more dysoxic. A decline in carbonate accumulation at ocean depths of greater than three kilometres took place synchronously with the peak of the MECO, signifying ocean acidification took place in the deep ocean. An abrupt decrease in lakewater salinity in western North America occurred during this warming interval. This warming is short lived, as benthic oxygen isotope records indicate a return to cooling at ~40 Ma. Late Eocene At the end of the Middle Eocene Climatic Optimum, cooling and the carbon dioxide drawdown continued through the late Eocene and into the Eocene–Oligocene transition around 34 Ma. The post-MECO cooling brought with it a major aridification trend in Asia. The cooling during the initial stages of the opening of the Drake Passage ~38.5 Ma was not global, as evidenced by an absence of cooling in the North Atlantic. During the cooling period, benthic oxygen isotopes show the possibility of ice creation and ice increase during this later cooling. The end of the Eocene and beginning of the Oligocene is marked with the massive expansion of area of the Antarctic ice sheet that was a major step into the icehouse climate. Multiple proxies, such as oxygen isotopes and alkenones, indicate that at the Eocene–Oligocene transition, the atmospheric carbon dioxide concentration had decreased to around 750–800 ppm, approximately twice that of present levels. Along with the decrease of atmospheric carbon dioxide reducing the global temperature, orbital factors in ice creation can be seen with 100,000-year and 400,000-year fluctuations in benthic oxygen isotope records. Another major contribution to the expansion of the ice sheet was the creation of the Antarctic Circumpolar Current. The creation of the Antarctic circumpolar current would isolate the cold water around the Antarctic, which would reduce heat transport to the Antarctic along with creating ocean gyres that result in the upwelling of colder bottom waters. The issue with this hypothesis of the consideration of this being a factor for the Eocene-Oligocene transition is the timing of the creation of the circulation is uncertain. For Drake Passage, sediments indicate the opening occurred ~41 Ma while tectonics indicate that this occurred ~32 Ma. Flora During the early-middle Eocene, forests covered most of the Earth including the poles. Tropical forests extended across much of modern Africa, South America, Central America, India, South-east Asia and China. Paratropical forests grew over North America, Europe and Russia, with broad-leafed evergreen and broad-leafed deciduous forests at higher latitudes.Polar forests were quite extensive. Fossils and even preserved remains of trees such as swamp cypress and dawn redwood from the Eocene have been found on Ellesmere Island in the Arctic. Even at that time, Ellesmere Island was only a few degrees in latitude further south than it is today. Fossils of subtropical and even tropical trees and plants from the Eocene also have been found in Greenland and Alaska. Tropical rainforests grew as far north as northern North America and Europe.Palm trees were growing as far north as Alaska and northern Europe during the early Eocene, although they became less abundant as the climate cooled. Dawn redwoods were far more extensive as well.The earliest definitive Eucalyptus fossils were dated from 51.9 Mya, and were found in the Laguna del Hunco deposit in Chubut province in Argentina.Cooling began mid-period, and by the end of the Eocene continental interiors had begun to dry, with forests thinning considerably in some areas. The newly evolved grasses were still confined to river banks and lake shores, and had not yet expanded into plains and savannas.The cooling also brought seasonal changes. Deciduous trees, better able to cope with large temperature changes, began to overtake evergreen tropical species. By the end of the period, deciduous forests covered large parts of the northern continents, including North America, Eurasia and the Arctic, and rainforests held on only in equatorial South America, Africa, India and Australia.Antarctica began the Eocene fringed with a warm temperate to sub-tropical rainforest. Pollen found in Prydz Bay from the Eocene suggest taiga forest existed there. It became much colder as the period progressed; the heat-loving tropical flora was wiped out, and by the beginning of the Oligocene, the continent hosted deciduous forests and vast stretches of tundra. Fauna During the Eocene, plants and marine faunas became quite modern. Many modern bird orders first appeared in the Eocene. The Eocene oceans were warm and teeming with fish and other sea life. Mammals The oldest known fossils of most of the modern mammal orders appear within a brief period during the early Eocene. At the beginning of the Eocene, several new mammal groups arrived in North America. These modern mammals, like artiodactyls, perissodactyls, and primates, had features like long, thin legs, feet, and hands capable of grasping, as well as differentiated teeth adapted for chewing. Dwarf forms reigned. All the members of the new mammal orders were small, under 10 kg; based on comparisons of tooth size, Eocene mammals were only 60% of the size of the primitive Palaeocene mammals that preceded them. They were also smaller than the mammals that followed them. It is assumed that the hot Eocene temperatures favored smaller animals that were better able to manage the heat.Both groups of modern ungulates (hoofed animals) became prevalent because of a major radiation between Europe and North America, along with carnivorous ungulates like Mesonyx. Early forms of many other modern mammalian orders appeared, including horses (most notably the Eohippus), bats, proboscidians (elephants), primates, rodents, and marsupials. Older primitive forms of mammals declined in variety and importance. Important Eocene land fauna fossil remains have been found in western North America, Europe, Patagonia, Egypt, and southeast Asia. Marine fauna are best known from South Asia and the southeast United States.Established megafauna of the Eocene include the Uintatherium, Arsinoitherium, and brontotheres, in which the former two, unlike the latter, did not belong to ungulates but groups that became extinct shortly after their establishments. Large terrestrial mammalian predators began to take form as the terrestrial carnivores like the Hyaenodon and Daphoenus (the earliest lineage of a once-successful predatory family known as bear dogs). Entelodonts meanwhile established themselves as some of the largest omnivores. The first nimravids, including Dinictis, established themselves as amongst the first feliforms to appear. Their groups became highly successful and continued to live past the Eocene. Basilosaurus is a very well-known Eocene whale, but whales as a group had become very diverse during the Eocene, which is when the major transitions from being terrestrial to fully aquatic in cetaceans occurred. The first sirenians were evolving at this time, and would eventually evolve into the extant manatees and dugongs. It is thought that millions of years after the Cretaceous-Paleogene extinction event, brain sizes of mammals now started to increase, "likely driven by a need for greater cognition in increasingly complex environments". Birds Eocene birds include some enigmatic groups with resemblances to modern forms, some of which continued from the Paleocene. Bird taxa of the Eocene include carnivorous psittaciforms, such as Messelasturidae, Halcyornithidae, large flightless forms such as Gastornis and Eleutherornis, long legged falcon Masillaraptor, ancient galliforms such as Gallinuloides, putative rail relatives of the family Songziidae, various pseudotooth birds such as Gigantornis, the ibis relative Rhynchaeites, primitive swifts of the genus Aegialornis, and primitive penguins such as Archaeospheniscus and Inkayacu. Reptiles Reptile fossils from this time, such as fossils of pythons and turtles, are abundant. Insects and arachnids Several rich fossil insect faunas are known from the Eocene, notably the Baltic amber found mainly along the south coast of the Baltic Sea, amber from the Paris Basin, France, the Fur Formation, Denmark, and the Bembridge Marls from the Isle of Wight, England. Insects found in Eocene deposits mostly belong to genera that exist today, though their range has often shifted since the Eocene. For instance the bibionid genus Plecia is common in fossil faunas from presently temperate areas, but only lives in the tropics and subtropics today. Gallery See also Bolca in Italy List of fossil sites (with link directory) London Clay Messel pit in Germany Wadi El Hitan in Egypt Notes References Further reading Ogg, Jim; June, 2004, Overview of Global Boundary Stratotype Sections and Points (GSSP's) Global Stratotype Sections and Points Accessed April 30, 2006. Stanley, Steven M. Earth System History. New York: W.H. Freeman and Company, 1999. ISBN 0-7167-2882-6 External links PaleoMap Project Paleos Eocene page PBS Deep Time: Eocene Eocene and Oligocene Fossils The UPenn Fossil Forest Project, focusing on the Eocene polar forests in Ellesmere Island, Canada Basilosaurus Primitive Eocene Whales Basilosaurus - The plesiosaur that wasn't.... Detailed maps of Tertiary Western North America Map of Eocene Earth Eocene Microfossils: 60+ images of Foraminifera Eocene Epoch. (2011). In Encyclopædia Britannica. Retrieved from Eocene Epoch \| geochronology	Store norske leksikon ID	{ "answer_start": [ 417 ], "text": [ "eocen" ] }
The Washington University Medical Center (WUMC), located in St. Louis, Missouri, is a large scale health-care focused commercial development located in St. Louis' Central West End neighborhood. The Washington University Medical Center Redevelopment Corporation focuses on developing public-private partnerships that promote infrastructure and housing development in the WUMC area. As of 2017, the executive director of WUMCRC is Brian Phillips. Although many of the institutions are affiliated with Washington University in St. Louis, most of the institutions of WUMC are independent of the university. Notably, the medical center is anchored by Barnes-Jewish Hospital and also houses the Washington University Medical School. History The Washington University Medical Center was incorporated in 1962. It is located on over 230 acres (93 ha) directly to the east of Forest Park. WUMC serves as the anchor of the Central West End community, a commercial and residential neighborhood with numerous shops, restaurants, and night spots.WUMC is accessible from the Kingshighway at I-64/US 40 or the Central West End station of the St. Louis Metrolink. Regular transportation is provided by rail and bus between WUMC and the other campuses of Washington University. Institutions The institutions of the Washington University Medical center are frequently ranked among the most prestigious and renowned hospitals in the United States. The major institutions in the Washington University Medical Center include: Alvin J. Siteman Cancer Center Barnes-Jewish Hospital Center for Advanced Medicine Central Institute for the Deaf Goldfarb School of Nursing at Barnes-Jewish College St. Louis Children's Hospital St. Louis College of Pharmacy Washington University School of MedicineOther institutions located at the campus are: Shriners Hospital for Children- St Louis References External links Alvin J. Siteman Cancer Center Center for Advanced Medicine Goldfarb School of Nursing	instance of	{ "answer_start": [ 1399 ], "text": [ "hospital" ] }
The Washington University Medical Center (WUMC), located in St. Louis, Missouri, is a large scale health-care focused commercial development located in St. Louis' Central West End neighborhood. The Washington University Medical Center Redevelopment Corporation focuses on developing public-private partnerships that promote infrastructure and housing development in the WUMC area. As of 2017, the executive director of WUMCRC is Brian Phillips. Although many of the institutions are affiliated with Washington University in St. Louis, most of the institutions of WUMC are independent of the university. Notably, the medical center is anchored by Barnes-Jewish Hospital and also houses the Washington University Medical School. History The Washington University Medical Center was incorporated in 1962. It is located on over 230 acres (93 ha) directly to the east of Forest Park. WUMC serves as the anchor of the Central West End community, a commercial and residential neighborhood with numerous shops, restaurants, and night spots.WUMC is accessible from the Kingshighway at I-64/US 40 or the Central West End station of the St. Louis Metrolink. Regular transportation is provided by rail and bus between WUMC and the other campuses of Washington University. Institutions The institutions of the Washington University Medical center are frequently ranked among the most prestigious and renowned hospitals in the United States. The major institutions in the Washington University Medical Center include: Alvin J. Siteman Cancer Center Barnes-Jewish Hospital Center for Advanced Medicine Central Institute for the Deaf Goldfarb School of Nursing at Barnes-Jewish College St. Louis Children's Hospital St. Louis College of Pharmacy Washington University School of MedicineOther institutions located at the campus are: Shriners Hospital for Children- St Louis References External links Alvin J. Siteman Cancer Center Center for Advanced Medicine Goldfarb School of Nursing	located in the administrative territorial entity	{ "answer_start": [ 60 ], "text": [ "St. Louis" ] }
The Psathyrellaceae are a family of dark-spored agarics that generally have rather soft, fragile fruiting bodies, and are characterized by black, dark brown, rarely reddish, or even pastel-colored spore prints. About 50% of species produce fruiting bodies that dissolve into ink-like ooze when the spores are mature via autodigestion. Prior to phylogenetic research based upon DNA comparisons, most of the species that autodigested were classified as Coprinaceae, which contained all of the inky-cap mushrooms. However, the type species of Coprinus, Coprinus comatus, and a few other species, were found to be more closely related to Agaricaceae. The former genus Coprinus was split between two families, and the name "Coprinaceae" became a synonym of Agaricaceae in its 21st-century phylogenetic redefinition. Note that in the 19th and early 20th centuries the family name Agaricaceae had far broader application, while in the late 20th century it had a narrower application. The family name Psathyrellaceae is based on the former Coprinaceae subfamily name Psathyrelloideae. The type genus Psathyrella consists of species that produce fruiting bodies which do not liquify via autodigestion. Psathyrella remained a polyphyletic genus until it was split into several genera including 3 new ones in 2015. Lacrymaria is another genus that does not autodigest its fruiting bodies. It is characterized by rough basidiospores and lamellar edges that exude beads of clear liquid when in prime condition, hence the Latin reference, lacryma (tears). Most Psathyrellaceae basidiospores have germ pores, and the pigment in the spore walls bleaches in concentrated sulfuric acid. This contrasts with another phylogenetically unrelated dark-spored genus, Panaeolus. Psathyrellaceae are saprotrophs or rarely mycoparasites on other agarics (e.g. Psathyrella epimyces). They often occur in nitrogen-rich habitats such as muck soils, dung, wet soft decayed wood, lawns, garden soils. Genera Coprinellus, Coprinopsis and Parasola Species in the genera Coprinellus, Coprinopsis and Parasola were until recently classified in the genus Coprinus, or in the case of a few Coprinellus species, in Pseudocoprinus. Based on molecular data, the genus Coprinus was divided, with these three genera moved to the family Psathyrellaceae. [1]. Coprinellus is a genus first described by Petter Karsten in 1879. Coprinopsis was split from the genus Coprinus based on molecular data. The species Coprinopsis cinerea is a model organism for mushroom-forming Basidiomycota, and its genome has recently been sequenced completely. See also List of Agaricales families References External links "The Genus Coprinus: The Inky Caps" by Michael Kuo, MushroomExpert.com, February, 2005. All about Inkcaps: Coprinus site of Kees Uljé – taxonomy and keys to coprinoid fungi. Fungus of the Month for May 2004: Coprinus comatus, the shaggy mane by Tom Volk, TomVolkFungi.net. – Includes information on how the genus Coprinus was recently segregated. Psathyrella Genus, Illinois Mycological Association (online).	KBpedia ID	{ "answer_start": [ 4 ], "text": [ "Psathyrellaceae" ] }
The Psathyrellaceae are a family of dark-spored agarics that generally have rather soft, fragile fruiting bodies, and are characterized by black, dark brown, rarely reddish, or even pastel-colored spore prints. About 50% of species produce fruiting bodies that dissolve into ink-like ooze when the spores are mature via autodigestion. Prior to phylogenetic research based upon DNA comparisons, most of the species that autodigested were classified as Coprinaceae, which contained all of the inky-cap mushrooms. However, the type species of Coprinus, Coprinus comatus, and a few other species, were found to be more closely related to Agaricaceae. The former genus Coprinus was split between two families, and the name "Coprinaceae" became a synonym of Agaricaceae in its 21st-century phylogenetic redefinition. Note that in the 19th and early 20th centuries the family name Agaricaceae had far broader application, while in the late 20th century it had a narrower application. The family name Psathyrellaceae is based on the former Coprinaceae subfamily name Psathyrelloideae. The type genus Psathyrella consists of species that produce fruiting bodies which do not liquify via autodigestion. Psathyrella remained a polyphyletic genus until it was split into several genera including 3 new ones in 2015. Lacrymaria is another genus that does not autodigest its fruiting bodies. It is characterized by rough basidiospores and lamellar edges that exude beads of clear liquid when in prime condition, hence the Latin reference, lacryma (tears). Most Psathyrellaceae basidiospores have germ pores, and the pigment in the spore walls bleaches in concentrated sulfuric acid. This contrasts with another phylogenetically unrelated dark-spored genus, Panaeolus. Psathyrellaceae are saprotrophs or rarely mycoparasites on other agarics (e.g. Psathyrella epimyces). They often occur in nitrogen-rich habitats such as muck soils, dung, wet soft decayed wood, lawns, garden soils. Genera Coprinellus, Coprinopsis and Parasola Species in the genera Coprinellus, Coprinopsis and Parasola were until recently classified in the genus Coprinus, or in the case of a few Coprinellus species, in Pseudocoprinus. Based on molecular data, the genus Coprinus was divided, with these three genera moved to the family Psathyrellaceae. [1]. Coprinellus is a genus first described by Petter Karsten in 1879. Coprinopsis was split from the genus Coprinus based on molecular data. The species Coprinopsis cinerea is a model organism for mushroom-forming Basidiomycota, and its genome has recently been sequenced completely. See also List of Agaricales families References External links "The Genus Coprinus: The Inky Caps" by Michael Kuo, MushroomExpert.com, February, 2005. All about Inkcaps: Coprinus site of Kees Uljé – taxonomy and keys to coprinoid fungi. Fungus of the Month for May 2004: Coprinus comatus, the shaggy mane by Tom Volk, TomVolkFungi.net. – Includes information on how the genus Coprinus was recently segregated. Psathyrella Genus, Illinois Mycological Association (online).	instance of	{ "answer_start": [ 2799 ], "text": [ "taxon" ] }
The Psathyrellaceae are a family of dark-spored agarics that generally have rather soft, fragile fruiting bodies, and are characterized by black, dark brown, rarely reddish, or even pastel-colored spore prints. About 50% of species produce fruiting bodies that dissolve into ink-like ooze when the spores are mature via autodigestion. Prior to phylogenetic research based upon DNA comparisons, most of the species that autodigested were classified as Coprinaceae, which contained all of the inky-cap mushrooms. However, the type species of Coprinus, Coprinus comatus, and a few other species, were found to be more closely related to Agaricaceae. The former genus Coprinus was split between two families, and the name "Coprinaceae" became a synonym of Agaricaceae in its 21st-century phylogenetic redefinition. Note that in the 19th and early 20th centuries the family name Agaricaceae had far broader application, while in the late 20th century it had a narrower application. The family name Psathyrellaceae is based on the former Coprinaceae subfamily name Psathyrelloideae. The type genus Psathyrella consists of species that produce fruiting bodies which do not liquify via autodigestion. Psathyrella remained a polyphyletic genus until it was split into several genera including 3 new ones in 2015. Lacrymaria is another genus that does not autodigest its fruiting bodies. It is characterized by rough basidiospores and lamellar edges that exude beads of clear liquid when in prime condition, hence the Latin reference, lacryma (tears). Most Psathyrellaceae basidiospores have germ pores, and the pigment in the spore walls bleaches in concentrated sulfuric acid. This contrasts with another phylogenetically unrelated dark-spored genus, Panaeolus. Psathyrellaceae are saprotrophs or rarely mycoparasites on other agarics (e.g. Psathyrella epimyces). They often occur in nitrogen-rich habitats such as muck soils, dung, wet soft decayed wood, lawns, garden soils. Genera Coprinellus, Coprinopsis and Parasola Species in the genera Coprinellus, Coprinopsis and Parasola were until recently classified in the genus Coprinus, or in the case of a few Coprinellus species, in Pseudocoprinus. Based on molecular data, the genus Coprinus was divided, with these three genera moved to the family Psathyrellaceae. [1]. Coprinellus is a genus first described by Petter Karsten in 1879. Coprinopsis was split from the genus Coprinus based on molecular data. The species Coprinopsis cinerea is a model organism for mushroom-forming Basidiomycota, and its genome has recently been sequenced completely. See also List of Agaricales families References External links "The Genus Coprinus: The Inky Caps" by Michael Kuo, MushroomExpert.com, February, 2005. All about Inkcaps: Coprinus site of Kees Uljé – taxonomy and keys to coprinoid fungi. Fungus of the Month for May 2004: Coprinus comatus, the shaggy mane by Tom Volk, TomVolkFungi.net. – Includes information on how the genus Coprinus was recently segregated. Psathyrella Genus, Illinois Mycological Association (online).	taxon rank	{ "answer_start": [ 26 ], "text": [ "family" ] }
The Psathyrellaceae are a family of dark-spored agarics that generally have rather soft, fragile fruiting bodies, and are characterized by black, dark brown, rarely reddish, or even pastel-colored spore prints. About 50% of species produce fruiting bodies that dissolve into ink-like ooze when the spores are mature via autodigestion. Prior to phylogenetic research based upon DNA comparisons, most of the species that autodigested were classified as Coprinaceae, which contained all of the inky-cap mushrooms. However, the type species of Coprinus, Coprinus comatus, and a few other species, were found to be more closely related to Agaricaceae. The former genus Coprinus was split between two families, and the name "Coprinaceae" became a synonym of Agaricaceae in its 21st-century phylogenetic redefinition. Note that in the 19th and early 20th centuries the family name Agaricaceae had far broader application, while in the late 20th century it had a narrower application. The family name Psathyrellaceae is based on the former Coprinaceae subfamily name Psathyrelloideae. The type genus Psathyrella consists of species that produce fruiting bodies which do not liquify via autodigestion. Psathyrella remained a polyphyletic genus until it was split into several genera including 3 new ones in 2015. Lacrymaria is another genus that does not autodigest its fruiting bodies. It is characterized by rough basidiospores and lamellar edges that exude beads of clear liquid when in prime condition, hence the Latin reference, lacryma (tears). Most Psathyrellaceae basidiospores have germ pores, and the pigment in the spore walls bleaches in concentrated sulfuric acid. This contrasts with another phylogenetically unrelated dark-spored genus, Panaeolus. Psathyrellaceae are saprotrophs or rarely mycoparasites on other agarics (e.g. Psathyrella epimyces). They often occur in nitrogen-rich habitats such as muck soils, dung, wet soft decayed wood, lawns, garden soils. Genera Coprinellus, Coprinopsis and Parasola Species in the genera Coprinellus, Coprinopsis and Parasola were until recently classified in the genus Coprinus, or in the case of a few Coprinellus species, in Pseudocoprinus. Based on molecular data, the genus Coprinus was divided, with these three genera moved to the family Psathyrellaceae. [1]. Coprinellus is a genus first described by Petter Karsten in 1879. Coprinopsis was split from the genus Coprinus based on molecular data. The species Coprinopsis cinerea is a model organism for mushroom-forming Basidiomycota, and its genome has recently been sequenced completely. See also List of Agaricales families References External links "The Genus Coprinus: The Inky Caps" by Michael Kuo, MushroomExpert.com, February, 2005. All about Inkcaps: Coprinus site of Kees Uljé – taxonomy and keys to coprinoid fungi. Fungus of the Month for May 2004: Coprinus comatus, the shaggy mane by Tom Volk, TomVolkFungi.net. – Includes information on how the genus Coprinus was recently segregated. Psathyrella Genus, Illinois Mycological Association (online).	parent taxon	{ "answer_start": [ 2616 ], "text": [ "Agaricales" ] }
The Psathyrellaceae are a family of dark-spored agarics that generally have rather soft, fragile fruiting bodies, and are characterized by black, dark brown, rarely reddish, or even pastel-colored spore prints. About 50% of species produce fruiting bodies that dissolve into ink-like ooze when the spores are mature via autodigestion. Prior to phylogenetic research based upon DNA comparisons, most of the species that autodigested were classified as Coprinaceae, which contained all of the inky-cap mushrooms. However, the type species of Coprinus, Coprinus comatus, and a few other species, were found to be more closely related to Agaricaceae. The former genus Coprinus was split between two families, and the name "Coprinaceae" became a synonym of Agaricaceae in its 21st-century phylogenetic redefinition. Note that in the 19th and early 20th centuries the family name Agaricaceae had far broader application, while in the late 20th century it had a narrower application. The family name Psathyrellaceae is based on the former Coprinaceae subfamily name Psathyrelloideae. The type genus Psathyrella consists of species that produce fruiting bodies which do not liquify via autodigestion. Psathyrella remained a polyphyletic genus until it was split into several genera including 3 new ones in 2015. Lacrymaria is another genus that does not autodigest its fruiting bodies. It is characterized by rough basidiospores and lamellar edges that exude beads of clear liquid when in prime condition, hence the Latin reference, lacryma (tears). Most Psathyrellaceae basidiospores have germ pores, and the pigment in the spore walls bleaches in concentrated sulfuric acid. This contrasts with another phylogenetically unrelated dark-spored genus, Panaeolus. Psathyrellaceae are saprotrophs or rarely mycoparasites on other agarics (e.g. Psathyrella epimyces). They often occur in nitrogen-rich habitats such as muck soils, dung, wet soft decayed wood, lawns, garden soils. Genera Coprinellus, Coprinopsis and Parasola Species in the genera Coprinellus, Coprinopsis and Parasola were until recently classified in the genus Coprinus, or in the case of a few Coprinellus species, in Pseudocoprinus. Based on molecular data, the genus Coprinus was divided, with these three genera moved to the family Psathyrellaceae. [1]. Coprinellus is a genus first described by Petter Karsten in 1879. Coprinopsis was split from the genus Coprinus based on molecular data. The species Coprinopsis cinerea is a model organism for mushroom-forming Basidiomycota, and its genome has recently been sequenced completely. See also List of Agaricales families References External links "The Genus Coprinus: The Inky Caps" by Michael Kuo, MushroomExpert.com, February, 2005. All about Inkcaps: Coprinus site of Kees Uljé – taxonomy and keys to coprinoid fungi. Fungus of the Month for May 2004: Coprinus comatus, the shaggy mane by Tom Volk, TomVolkFungi.net. – Includes information on how the genus Coprinus was recently segregated. Psathyrella Genus, Illinois Mycological Association (online).	taxon name	{ "answer_start": [ 4 ], "text": [ "Psathyrellaceae" ] }
The Psathyrellaceae are a family of dark-spored agarics that generally have rather soft, fragile fruiting bodies, and are characterized by black, dark brown, rarely reddish, or even pastel-colored spore prints. About 50% of species produce fruiting bodies that dissolve into ink-like ooze when the spores are mature via autodigestion. Prior to phylogenetic research based upon DNA comparisons, most of the species that autodigested were classified as Coprinaceae, which contained all of the inky-cap mushrooms. However, the type species of Coprinus, Coprinus comatus, and a few other species, were found to be more closely related to Agaricaceae. The former genus Coprinus was split between two families, and the name "Coprinaceae" became a synonym of Agaricaceae in its 21st-century phylogenetic redefinition. Note that in the 19th and early 20th centuries the family name Agaricaceae had far broader application, while in the late 20th century it had a narrower application. The family name Psathyrellaceae is based on the former Coprinaceae subfamily name Psathyrelloideae. The type genus Psathyrella consists of species that produce fruiting bodies which do not liquify via autodigestion. Psathyrella remained a polyphyletic genus until it was split into several genera including 3 new ones in 2015. Lacrymaria is another genus that does not autodigest its fruiting bodies. It is characterized by rough basidiospores and lamellar edges that exude beads of clear liquid when in prime condition, hence the Latin reference, lacryma (tears). Most Psathyrellaceae basidiospores have germ pores, and the pigment in the spore walls bleaches in concentrated sulfuric acid. This contrasts with another phylogenetically unrelated dark-spored genus, Panaeolus. Psathyrellaceae are saprotrophs or rarely mycoparasites on other agarics (e.g. Psathyrella epimyces). They often occur in nitrogen-rich habitats such as muck soils, dung, wet soft decayed wood, lawns, garden soils. Genera Coprinellus, Coprinopsis and Parasola Species in the genera Coprinellus, Coprinopsis and Parasola were until recently classified in the genus Coprinus, or in the case of a few Coprinellus species, in Pseudocoprinus. Based on molecular data, the genus Coprinus was divided, with these three genera moved to the family Psathyrellaceae. [1]. Coprinellus is a genus first described by Petter Karsten in 1879. Coprinopsis was split from the genus Coprinus based on molecular data. The species Coprinopsis cinerea is a model organism for mushroom-forming Basidiomycota, and its genome has recently been sequenced completely. See also List of Agaricales families References External links "The Genus Coprinus: The Inky Caps" by Michael Kuo, MushroomExpert.com, February, 2005. All about Inkcaps: Coprinus site of Kees Uljé – taxonomy and keys to coprinoid fungi. Fungus of the Month for May 2004: Coprinus comatus, the shaggy mane by Tom Volk, TomVolkFungi.net. – Includes information on how the genus Coprinus was recently segregated. Psathyrella Genus, Illinois Mycological Association (online).	Commons category	{ "answer_start": [ 4 ], "text": [ "Psathyrellaceae" ] }
The 2018 BRD Bucharest Open was a tennis tournament played on outdoor clay courts. It was the fifth edition of the tournament and part of the International category of the 2018 WTA Tour. It was held from 16 to 22 July 2018 at the Arenele BNR in Bucharest, Romania. Points and prize money Point distribution Prize money Singles main-draw entrants Seeds 1 Rankings as of 2 July 2018. Other entrants The following players received wildcards into the singles main draw: Miriam Bulgaru Andreea Roșca Elena-Gabriela RuseThe following players received entry using a protected ranking into the singles main draw: Laura SiegemundThe following players received entry from the qualifying draw: Irina Bara Çağla Büyükakçay Claire Liu Rebecca Šramková Withdrawals Before the tournament Sara Errani → replaced by Ons Jabeur Kaia Kanepi → replaced by Ysaline Bonaventure Monica Niculescu → replaced by Viktoriya Tomova Yulia Putintseva → replaced by Jasmine Paolini Carla Suárez Navarro → replaced by Vera Zvonareva Retirements Polona Hercog WTA doubles main-draw entrants Seeds Rankings are as of July 2, 2018 Other entrants The following pairs received wildcards into the doubles main draw: Irina-Camelia Begu / Andreea Mitu Anna Bondár / Miriam Bulgaru Champions Singles Anastasija Sevastova def. Petra Martić, 7–6(7–4), 6–2 Doubles Irina-Camelia Begu / Andreea Mitu def. Danka Kovinić / Maryna Zanevska 6–3, 6–4 References External links Official website	country	{ "answer_start": [ 256 ], "text": [ "Romania" ] }
The 2018 BRD Bucharest Open was a tennis tournament played on outdoor clay courts. It was the fifth edition of the tournament and part of the International category of the 2018 WTA Tour. It was held from 16 to 22 July 2018 at the Arenele BNR in Bucharest, Romania. Points and prize money Point distribution Prize money Singles main-draw entrants Seeds 1 Rankings as of 2 July 2018. Other entrants The following players received wildcards into the singles main draw: Miriam Bulgaru Andreea Roșca Elena-Gabriela RuseThe following players received entry using a protected ranking into the singles main draw: Laura SiegemundThe following players received entry from the qualifying draw: Irina Bara Çağla Büyükakçay Claire Liu Rebecca Šramková Withdrawals Before the tournament Sara Errani → replaced by Ons Jabeur Kaia Kanepi → replaced by Ysaline Bonaventure Monica Niculescu → replaced by Viktoriya Tomova Yulia Putintseva → replaced by Jasmine Paolini Carla Suárez Navarro → replaced by Vera Zvonareva Retirements Polona Hercog WTA doubles main-draw entrants Seeds Rankings are as of July 2, 2018 Other entrants The following pairs received wildcards into the doubles main draw: Irina-Camelia Begu / Andreea Mitu Anna Bondár / Miriam Bulgaru Champions Singles Anastasija Sevastova def. Petra Martić, 7–6(7–4), 6–2 Doubles Irina-Camelia Begu / Andreea Mitu def. Danka Kovinić / Maryna Zanevska 6–3, 6–4 References External links Official website	instance of	{ "answer_start": [ 13 ], "text": [ "Bucharest Open" ] }
The 2018 BRD Bucharest Open was a tennis tournament played on outdoor clay courts. It was the fifth edition of the tournament and part of the International category of the 2018 WTA Tour. It was held from 16 to 22 July 2018 at the Arenele BNR in Bucharest, Romania. Points and prize money Point distribution Prize money Singles main-draw entrants Seeds 1 Rankings as of 2 July 2018. Other entrants The following players received wildcards into the singles main draw: Miriam Bulgaru Andreea Roșca Elena-Gabriela RuseThe following players received entry using a protected ranking into the singles main draw: Laura SiegemundThe following players received entry from the qualifying draw: Irina Bara Çağla Büyükakçay Claire Liu Rebecca Šramková Withdrawals Before the tournament Sara Errani → replaced by Ons Jabeur Kaia Kanepi → replaced by Ysaline Bonaventure Monica Niculescu → replaced by Viktoriya Tomova Yulia Putintseva → replaced by Jasmine Paolini Carla Suárez Navarro → replaced by Vera Zvonareva Retirements Polona Hercog WTA doubles main-draw entrants Seeds Rankings are as of July 2, 2018 Other entrants The following pairs received wildcards into the doubles main draw: Irina-Camelia Begu / Andreea Mitu Anna Bondár / Miriam Bulgaru Champions Singles Anastasija Sevastova def. Petra Martić, 7–6(7–4), 6–2 Doubles Irina-Camelia Begu / Andreea Mitu def. Danka Kovinić / Maryna Zanevska 6–3, 6–4 References External links Official website	located in the administrative territorial entity	{ "answer_start": [ 13 ], "text": [ "Bucharest" ] }
The 2018 BRD Bucharest Open was a tennis tournament played on outdoor clay courts. It was the fifth edition of the tournament and part of the International category of the 2018 WTA Tour. It was held from 16 to 22 July 2018 at the Arenele BNR in Bucharest, Romania. Points and prize money Point distribution Prize money Singles main-draw entrants Seeds 1 Rankings as of 2 July 2018. Other entrants The following players received wildcards into the singles main draw: Miriam Bulgaru Andreea Roșca Elena-Gabriela RuseThe following players received entry using a protected ranking into the singles main draw: Laura SiegemundThe following players received entry from the qualifying draw: Irina Bara Çağla Büyükakçay Claire Liu Rebecca Šramková Withdrawals Before the tournament Sara Errani → replaced by Ons Jabeur Kaia Kanepi → replaced by Ysaline Bonaventure Monica Niculescu → replaced by Viktoriya Tomova Yulia Putintseva → replaced by Jasmine Paolini Carla Suárez Navarro → replaced by Vera Zvonareva Retirements Polona Hercog WTA doubles main-draw entrants Seeds Rankings are as of July 2, 2018 Other entrants The following pairs received wildcards into the doubles main draw: Irina-Camelia Begu / Andreea Mitu Anna Bondár / Miriam Bulgaru Champions Singles Anastasija Sevastova def. Petra Martić, 7–6(7–4), 6–2 Doubles Irina-Camelia Begu / Andreea Mitu def. Danka Kovinić / Maryna Zanevska 6–3, 6–4 References External links Official website	part of	{ "answer_start": [ 172 ], "text": [ "2018 WTA Tour" ] }
The 2018 BRD Bucharest Open was a tennis tournament played on outdoor clay courts. It was the fifth edition of the tournament and part of the International category of the 2018 WTA Tour. It was held from 16 to 22 July 2018 at the Arenele BNR in Bucharest, Romania. Points and prize money Point distribution Prize money Singles main-draw entrants Seeds 1 Rankings as of 2 July 2018. Other entrants The following players received wildcards into the singles main draw: Miriam Bulgaru Andreea Roșca Elena-Gabriela RuseThe following players received entry using a protected ranking into the singles main draw: Laura SiegemundThe following players received entry from the qualifying draw: Irina Bara Çağla Büyükakçay Claire Liu Rebecca Šramková Withdrawals Before the tournament Sara Errani → replaced by Ons Jabeur Kaia Kanepi → replaced by Ysaline Bonaventure Monica Niculescu → replaced by Viktoriya Tomova Yulia Putintseva → replaced by Jasmine Paolini Carla Suárez Navarro → replaced by Vera Zvonareva Retirements Polona Hercog WTA doubles main-draw entrants Seeds Rankings are as of July 2, 2018 Other entrants The following pairs received wildcards into the doubles main draw: Irina-Camelia Begu / Andreea Mitu Anna Bondár / Miriam Bulgaru Champions Singles Anastasija Sevastova def. Petra Martić, 7–6(7–4), 6–2 Doubles Irina-Camelia Begu / Andreea Mitu def. Danka Kovinić / Maryna Zanevska 6–3, 6–4 References External links Official website	sport	{ "answer_start": [ 34 ], "text": [ "tennis" ] }
Horoka Dam (Japanese: 幌加ダム) is a rockfill dam located in Hokkaido Prefecture in Japan. The dam is used for power production. The catchment area of the dam is 256.3 km2. The dam impounds about 8 ha of land when full and can store 493 thousand cubic meters of water. The construction of the dam was completed in 1965. == References ==	country	{ "answer_start": [ 12 ], "text": [ "Japan" ] }
Horoka Dam (Japanese: 幌加ダム) is a rockfill dam located in Hokkaido Prefecture in Japan. The dam is used for power production. The catchment area of the dam is 256.3 km2. The dam impounds about 8 ha of land when full and can store 493 thousand cubic meters of water. The construction of the dam was completed in 1965. == References ==	instance of	{ "answer_start": [ 42 ], "text": [ "dam" ] }
Horoka Dam (Japanese: 幌加ダム) is a rockfill dam located in Hokkaido Prefecture in Japan. The dam is used for power production. The catchment area of the dam is 256.3 km2. The dam impounds about 8 ha of land when full and can store 493 thousand cubic meters of water. The construction of the dam was completed in 1965. == References ==	located in the administrative territorial entity	{ "answer_start": [ 57 ], "text": [ "Hokkaido" ] }
Sir Reginald Blair, 1st Baronet (8 November 1881 – 18 September 1962) was a British politician. He served as a Conservative Member of Parliament (MP) from 1912 to 1922, and from 1935 to 1945. Early life Blair was born in Glasgow in 1881. He was educated at Kelvinside Academy and Glasgow University, after which he became an accountant. Blair was married, and had a son Malcolm Reginald Blair, who died on 31 May 1940, aged 33, while in active service in World War II. Early career Blair was first elected to Parliament in a by-election in the Bow and Bromley constituency on 26 November 1912. The by-election was caused by George Lansbury, the Labour MP, taking the Chiltern Hundreds, a way of resigning from the House of Commons. Lansbury caused the by-election to highlight the issue of women's suffrage, but the Labour Party did not endorse him as their candidate so he stood as an independent on a platform of "Votes for Women". Labour did not stand a candidate, and Blair won the by-election by a majority of 751 votes. For the first two years of World War I, Blair served with the British Expeditionary Force and was mentioned in dispatches. From 1916 to 1918, he served as a field cashier with the temporary rank of Major. Reginald Blair held his seat in the 1918 general election, but was defeated in 1922 by Lansbury, who remained Bow and Bromley's MP until his death in 1940. Following his election defeat, Blair was knighted, and became the Chairman of the Racehorse Betting Control Board. Later career In the 1935 general election, Reginald Blair was elected as MP for Hendon, succeeding the Conservative Philip Cunliffe-Lister. On 19 June 1945, he was created a baronet, of Harrow Weald in the County of Middlesex. His Hendon seat was abolished for the 1945 general election, and he retired. Reginald Blair died in 1962, aged 80, and was buried in Harrow Cemetery in Harrow, London. The baronetcy became extinct on his death. References Specific GeneralLeigh Rayment's Historical List of MPs British Parliamentary Election Results 1918–1949, compiled and edited by F.W.S. Craig (The Macmillan Press 1977) Who's Who of British Members of Parliament: Volume III 1919–1945, edited by M. Stenton and S. Lees (The Harvester Press 1976) External links Hansard 1803–2005: contributions in Parliament by Sir Reginald Blair	educated at	{ "answer_start": [ 258 ], "text": [ "Kelvinside Academy" ] }
Sir Reginald Blair, 1st Baronet (8 November 1881 – 18 September 1962) was a British politician. He served as a Conservative Member of Parliament (MP) from 1912 to 1922, and from 1935 to 1945. Early life Blair was born in Glasgow in 1881. He was educated at Kelvinside Academy and Glasgow University, after which he became an accountant. Blair was married, and had a son Malcolm Reginald Blair, who died on 31 May 1940, aged 33, while in active service in World War II. Early career Blair was first elected to Parliament in a by-election in the Bow and Bromley constituency on 26 November 1912. The by-election was caused by George Lansbury, the Labour MP, taking the Chiltern Hundreds, a way of resigning from the House of Commons. Lansbury caused the by-election to highlight the issue of women's suffrage, but the Labour Party did not endorse him as their candidate so he stood as an independent on a platform of "Votes for Women". Labour did not stand a candidate, and Blair won the by-election by a majority of 751 votes. For the first two years of World War I, Blair served with the British Expeditionary Force and was mentioned in dispatches. From 1916 to 1918, he served as a field cashier with the temporary rank of Major. Reginald Blair held his seat in the 1918 general election, but was defeated in 1922 by Lansbury, who remained Bow and Bromley's MP until his death in 1940. Following his election defeat, Blair was knighted, and became the Chairman of the Racehorse Betting Control Board. Later career In the 1935 general election, Reginald Blair was elected as MP for Hendon, succeeding the Conservative Philip Cunliffe-Lister. On 19 June 1945, he was created a baronet, of Harrow Weald in the County of Middlesex. His Hendon seat was abolished for the 1945 general election, and he retired. Reginald Blair died in 1962, aged 80, and was buried in Harrow Cemetery in Harrow, London. The baronetcy became extinct on his death. References Specific GeneralLeigh Rayment's Historical List of MPs British Parliamentary Election Results 1918–1949, compiled and edited by F.W.S. Craig (The Macmillan Press 1977) Who's Who of British Members of Parliament: Volume III 1919–1945, edited by M. Stenton and S. Lees (The Harvester Press 1976) External links Hansard 1803–2005: contributions in Parliament by Sir Reginald Blair	noble title	{ "answer_start": [ 1679 ], "text": [ "baronet" ] }
Sir Reginald Blair, 1st Baronet (8 November 1881 – 18 September 1962) was a British politician. He served as a Conservative Member of Parliament (MP) from 1912 to 1922, and from 1935 to 1945. Early life Blair was born in Glasgow in 1881. He was educated at Kelvinside Academy and Glasgow University, after which he became an accountant. Blair was married, and had a son Malcolm Reginald Blair, who died on 31 May 1940, aged 33, while in active service in World War II. Early career Blair was first elected to Parliament in a by-election in the Bow and Bromley constituency on 26 November 1912. The by-election was caused by George Lansbury, the Labour MP, taking the Chiltern Hundreds, a way of resigning from the House of Commons. Lansbury caused the by-election to highlight the issue of women's suffrage, but the Labour Party did not endorse him as their candidate so he stood as an independent on a platform of "Votes for Women". Labour did not stand a candidate, and Blair won the by-election by a majority of 751 votes. For the first two years of World War I, Blair served with the British Expeditionary Force and was mentioned in dispatches. From 1916 to 1918, he served as a field cashier with the temporary rank of Major. Reginald Blair held his seat in the 1918 general election, but was defeated in 1922 by Lansbury, who remained Bow and Bromley's MP until his death in 1940. Following his election defeat, Blair was knighted, and became the Chairman of the Racehorse Betting Control Board. Later career In the 1935 general election, Reginald Blair was elected as MP for Hendon, succeeding the Conservative Philip Cunliffe-Lister. On 19 June 1945, he was created a baronet, of Harrow Weald in the County of Middlesex. His Hendon seat was abolished for the 1945 general election, and he retired. Reginald Blair died in 1962, aged 80, and was buried in Harrow Cemetery in Harrow, London. The baronetcy became extinct on his death. References Specific GeneralLeigh Rayment's Historical List of MPs British Parliamentary Election Results 1918–1949, compiled and edited by F.W.S. Craig (The Macmillan Press 1977) Who's Who of British Members of Parliament: Volume III 1919–1945, edited by M. Stenton and S. Lees (The Harvester Press 1976) External links Hansard 1803–2005: contributions in Parliament by Sir Reginald Blair	occupation	{ "answer_start": [ 84 ], "text": [ "politician" ] }
Sir Reginald Blair, 1st Baronet (8 November 1881 – 18 September 1962) was a British politician. He served as a Conservative Member of Parliament (MP) from 1912 to 1922, and from 1935 to 1945. Early life Blair was born in Glasgow in 1881. He was educated at Kelvinside Academy and Glasgow University, after which he became an accountant. Blair was married, and had a son Malcolm Reginald Blair, who died on 31 May 1940, aged 33, while in active service in World War II. Early career Blair was first elected to Parliament in a by-election in the Bow and Bromley constituency on 26 November 1912. The by-election was caused by George Lansbury, the Labour MP, taking the Chiltern Hundreds, a way of resigning from the House of Commons. Lansbury caused the by-election to highlight the issue of women's suffrage, but the Labour Party did not endorse him as their candidate so he stood as an independent on a platform of "Votes for Women". Labour did not stand a candidate, and Blair won the by-election by a majority of 751 votes. For the first two years of World War I, Blair served with the British Expeditionary Force and was mentioned in dispatches. From 1916 to 1918, he served as a field cashier with the temporary rank of Major. Reginald Blair held his seat in the 1918 general election, but was defeated in 1922 by Lansbury, who remained Bow and Bromley's MP until his death in 1940. Following his election defeat, Blair was knighted, and became the Chairman of the Racehorse Betting Control Board. Later career In the 1935 general election, Reginald Blair was elected as MP for Hendon, succeeding the Conservative Philip Cunliffe-Lister. On 19 June 1945, he was created a baronet, of Harrow Weald in the County of Middlesex. His Hendon seat was abolished for the 1945 general election, and he retired. Reginald Blair died in 1962, aged 80, and was buried in Harrow Cemetery in Harrow, London. The baronetcy became extinct on his death. References Specific GeneralLeigh Rayment's Historical List of MPs British Parliamentary Election Results 1918–1949, compiled and edited by F.W.S. Craig (The Macmillan Press 1977) Who's Who of British Members of Parliament: Volume III 1919–1945, edited by M. Stenton and S. Lees (The Harvester Press 1976) External links Hansard 1803–2005: contributions in Parliament by Sir Reginald Blair	conflict	{ "answer_start": [ 456 ], "text": [ "World War I" ] }
Sir Reginald Blair, 1st Baronet (8 November 1881 – 18 September 1962) was a British politician. He served as a Conservative Member of Parliament (MP) from 1912 to 1922, and from 1935 to 1945. Early life Blair was born in Glasgow in 1881. He was educated at Kelvinside Academy and Glasgow University, after which he became an accountant. Blair was married, and had a son Malcolm Reginald Blair, who died on 31 May 1940, aged 33, while in active service in World War II. Early career Blair was first elected to Parliament in a by-election in the Bow and Bromley constituency on 26 November 1912. The by-election was caused by George Lansbury, the Labour MP, taking the Chiltern Hundreds, a way of resigning from the House of Commons. Lansbury caused the by-election to highlight the issue of women's suffrage, but the Labour Party did not endorse him as their candidate so he stood as an independent on a platform of "Votes for Women". Labour did not stand a candidate, and Blair won the by-election by a majority of 751 votes. For the first two years of World War I, Blair served with the British Expeditionary Force and was mentioned in dispatches. From 1916 to 1918, he served as a field cashier with the temporary rank of Major. Reginald Blair held his seat in the 1918 general election, but was defeated in 1922 by Lansbury, who remained Bow and Bromley's MP until his death in 1940. Following his election defeat, Blair was knighted, and became the Chairman of the Racehorse Betting Control Board. Later career In the 1935 general election, Reginald Blair was elected as MP for Hendon, succeeding the Conservative Philip Cunliffe-Lister. On 19 June 1945, he was created a baronet, of Harrow Weald in the County of Middlesex. His Hendon seat was abolished for the 1945 general election, and he retired. Reginald Blair died in 1962, aged 80, and was buried in Harrow Cemetery in Harrow, London. The baronetcy became extinct on his death. References Specific GeneralLeigh Rayment's Historical List of MPs British Parliamentary Election Results 1918–1949, compiled and edited by F.W.S. Craig (The Macmillan Press 1977) Who's Who of British Members of Parliament: Volume III 1919–1945, edited by M. Stenton and S. Lees (The Harvester Press 1976) External links Hansard 1803–2005: contributions in Parliament by Sir Reginald Blair	family name	{ "answer_start": [ 13 ], "text": [ "Blair" ] }
Sir Reginald Blair, 1st Baronet (8 November 1881 – 18 September 1962) was a British politician. He served as a Conservative Member of Parliament (MP) from 1912 to 1922, and from 1935 to 1945. Early life Blair was born in Glasgow in 1881. He was educated at Kelvinside Academy and Glasgow University, after which he became an accountant. Blair was married, and had a son Malcolm Reginald Blair, who died on 31 May 1940, aged 33, while in active service in World War II. Early career Blair was first elected to Parliament in a by-election in the Bow and Bromley constituency on 26 November 1912. The by-election was caused by George Lansbury, the Labour MP, taking the Chiltern Hundreds, a way of resigning from the House of Commons. Lansbury caused the by-election to highlight the issue of women's suffrage, but the Labour Party did not endorse him as their candidate so he stood as an independent on a platform of "Votes for Women". Labour did not stand a candidate, and Blair won the by-election by a majority of 751 votes. For the first two years of World War I, Blair served with the British Expeditionary Force and was mentioned in dispatches. From 1916 to 1918, he served as a field cashier with the temporary rank of Major. Reginald Blair held his seat in the 1918 general election, but was defeated in 1922 by Lansbury, who remained Bow and Bromley's MP until his death in 1940. Following his election defeat, Blair was knighted, and became the Chairman of the Racehorse Betting Control Board. Later career In the 1935 general election, Reginald Blair was elected as MP for Hendon, succeeding the Conservative Philip Cunliffe-Lister. On 19 June 1945, he was created a baronet, of Harrow Weald in the County of Middlesex. His Hendon seat was abolished for the 1945 general election, and he retired. Reginald Blair died in 1962, aged 80, and was buried in Harrow Cemetery in Harrow, London. The baronetcy became extinct on his death. References Specific GeneralLeigh Rayment's Historical List of MPs British Parliamentary Election Results 1918–1949, compiled and edited by F.W.S. Craig (The Macmillan Press 1977) Who's Who of British Members of Parliament: Volume III 1919–1945, edited by M. Stenton and S. Lees (The Harvester Press 1976) External links Hansard 1803–2005: contributions in Parliament by Sir Reginald Blair	given name	{ "answer_start": [ 4 ], "text": [ "Reginald" ] }
Sir Reginald Blair, 1st Baronet (8 November 1881 – 18 September 1962) was a British politician. He served as a Conservative Member of Parliament (MP) from 1912 to 1922, and from 1935 to 1945. Early life Blair was born in Glasgow in 1881. He was educated at Kelvinside Academy and Glasgow University, after which he became an accountant. Blair was married, and had a son Malcolm Reginald Blair, who died on 31 May 1940, aged 33, while in active service in World War II. Early career Blair was first elected to Parliament in a by-election in the Bow and Bromley constituency on 26 November 1912. The by-election was caused by George Lansbury, the Labour MP, taking the Chiltern Hundreds, a way of resigning from the House of Commons. Lansbury caused the by-election to highlight the issue of women's suffrage, but the Labour Party did not endorse him as their candidate so he stood as an independent on a platform of "Votes for Women". Labour did not stand a candidate, and Blair won the by-election by a majority of 751 votes. For the first two years of World War I, Blair served with the British Expeditionary Force and was mentioned in dispatches. From 1916 to 1918, he served as a field cashier with the temporary rank of Major. Reginald Blair held his seat in the 1918 general election, but was defeated in 1922 by Lansbury, who remained Bow and Bromley's MP until his death in 1940. Following his election defeat, Blair was knighted, and became the Chairman of the Racehorse Betting Control Board. Later career In the 1935 general election, Reginald Blair was elected as MP for Hendon, succeeding the Conservative Philip Cunliffe-Lister. On 19 June 1945, he was created a baronet, of Harrow Weald in the County of Middlesex. His Hendon seat was abolished for the 1945 general election, and he retired. Reginald Blair died in 1962, aged 80, and was buried in Harrow Cemetery in Harrow, London. The baronetcy became extinct on his death. References Specific GeneralLeigh Rayment's Historical List of MPs British Parliamentary Election Results 1918–1949, compiled and edited by F.W.S. Craig (The Macmillan Press 1977) Who's Who of British Members of Parliament: Volume III 1919–1945, edited by M. Stenton and S. Lees (The Harvester Press 1976) External links Hansard 1803–2005: contributions in Parliament by Sir Reginald Blair	work location	{ "answer_start": [ 1892 ], "text": [ "London" ] }
Sir Reginald Blair, 1st Baronet (8 November 1881 – 18 September 1962) was a British politician. He served as a Conservative Member of Parliament (MP) from 1912 to 1922, and from 1935 to 1945. Early life Blair was born in Glasgow in 1881. He was educated at Kelvinside Academy and Glasgow University, after which he became an accountant. Blair was married, and had a son Malcolm Reginald Blair, who died on 31 May 1940, aged 33, while in active service in World War II. Early career Blair was first elected to Parliament in a by-election in the Bow and Bromley constituency on 26 November 1912. The by-election was caused by George Lansbury, the Labour MP, taking the Chiltern Hundreds, a way of resigning from the House of Commons. Lansbury caused the by-election to highlight the issue of women's suffrage, but the Labour Party did not endorse him as their candidate so he stood as an independent on a platform of "Votes for Women". Labour did not stand a candidate, and Blair won the by-election by a majority of 751 votes. For the first two years of World War I, Blair served with the British Expeditionary Force and was mentioned in dispatches. From 1916 to 1918, he served as a field cashier with the temporary rank of Major. Reginald Blair held his seat in the 1918 general election, but was defeated in 1922 by Lansbury, who remained Bow and Bromley's MP until his death in 1940. Following his election defeat, Blair was knighted, and became the Chairman of the Racehorse Betting Control Board. Later career In the 1935 general election, Reginald Blair was elected as MP for Hendon, succeeding the Conservative Philip Cunliffe-Lister. On 19 June 1945, he was created a baronet, of Harrow Weald in the County of Middlesex. His Hendon seat was abolished for the 1945 general election, and he retired. Reginald Blair died in 1962, aged 80, and was buried in Harrow Cemetery in Harrow, London. The baronetcy became extinct on his death. References Specific GeneralLeigh Rayment's Historical List of MPs British Parliamentary Election Results 1918–1949, compiled and edited by F.W.S. Craig (The Macmillan Press 1977) Who's Who of British Members of Parliament: Volume III 1919–1945, edited by M. Stenton and S. Lees (The Harvester Press 1976) External links Hansard 1803–2005: contributions in Parliament by Sir Reginald Blair	name in native language	{ "answer_start": [ 4 ], "text": [ "Reginald Blair" ] }
Great Britain has been participating at the Deaflympics since 1924 and has earned 249 medals. Medal tallies Summer Deaflympics See also United Kingdom at the Paralympics United Kingdom at the Olympics References External links 2017 Deaflympics Archived 2019-12-30 at the Wayback Machine	country	{ "answer_start": [ 138 ], "text": [ "United Kingdom" ] }
Great Britain has been participating at the Deaflympics since 1924 and has earned 249 medals. Medal tallies Summer Deaflympics See also United Kingdom at the Paralympics United Kingdom at the Olympics References External links 2017 Deaflympics Archived 2019-12-30 at the Wayback Machine	participant in	{ "answer_start": [ 45 ], "text": [ "Deaflympics" ] }
Head of a Woman may refer to: Head of a Woman (Bosch), a Hieronymus Bosch painting fragment. Head of a Woman (Leonardo da Vinci), painted around 1500 Head of a Woman (Delacroix), 1823 Head of a Woman (Fernande Olivier) by Pablo Picasso, 1909 See also Woman's Head	instance of	{ "answer_start": [ 75 ], "text": [ "painting" ] }
Head of a Woman may refer to: Head of a Woman (Bosch), a Hieronymus Bosch painting fragment. Head of a Woman (Leonardo da Vinci), painted around 1500 Head of a Woman (Delacroix), 1823 Head of a Woman (Fernande Olivier) by Pablo Picasso, 1909 See also Woman's Head	creator	{ "answer_start": [ 111 ], "text": [ "Leonardo da Vinci" ] }
Head of a Woman may refer to: Head of a Woman (Bosch), a Hieronymus Bosch painting fragment. Head of a Woman (Leonardo da Vinci), painted around 1500 Head of a Woman (Delacroix), 1823 Head of a Woman (Fernande Olivier) by Pablo Picasso, 1909 See also Woman's Head	title	{ "answer_start": [ 0 ], "text": [ "Head of a Woman" ] }
Head of a Woman may refer to: Head of a Woman (Bosch), a Hieronymus Bosch painting fragment. Head of a Woman (Leonardo da Vinci), painted around 1500 Head of a Woman (Delacroix), 1823 Head of a Woman (Fernande Olivier) by Pablo Picasso, 1909 See also Woman's Head	based on	{ "answer_start": [ 0 ], "text": [ "Head of a Woman" ] }
Head of a Woman may refer to: Head of a Woman (Bosch), a Hieronymus Bosch painting fragment. Head of a Woman (Leonardo da Vinci), painted around 1500 Head of a Woman (Delacroix), 1823 Head of a Woman (Fernande Olivier) by Pablo Picasso, 1909 See also Woman's Head	height	{ "answer_start": [ 180 ], "text": [ "18" ] }
Head of a Woman may refer to: Head of a Woman (Bosch), a Hieronymus Bosch painting fragment. Head of a Woman (Leonardo da Vinci), painted around 1500 Head of a Woman (Delacroix), 1823 Head of a Woman (Fernande Olivier) by Pablo Picasso, 1909 See also Woman's Head	catalog code	{ "answer_start": [ 147 ], "text": [ "50" ] }
Head of a Woman may refer to: Head of a Woman (Bosch), a Hieronymus Bosch painting fragment. Head of a Woman (Leonardo da Vinci), painted around 1500 Head of a Woman (Delacroix), 1823 Head of a Woman (Fernande Olivier) by Pablo Picasso, 1909 See also Woman's Head	author name string	{ "answer_start": [ 229 ], "text": [ "Picasso" ] }
Head of a Woman may refer to: Head of a Woman (Bosch), a Hieronymus Bosch painting fragment. Head of a Woman (Leonardo da Vinci), painted around 1500 Head of a Woman (Delacroix), 1823 Head of a Woman (Fernande Olivier) by Pablo Picasso, 1909 See also Woman's Head	width	{ "answer_start": [ 147 ], "text": [ "50" ] }
The Cévennes ( say-VEN, French: [sevɛn] (listen); Occitan: Cevenas) is a cultural region and range of mountains in south-central France, on the south-east edge of the Massif Central. It covers parts of the départements of Ardèche, Gard, Hérault and Lozère. Rich in geographical, natural, and cultural significance, portions of the region are protected within the Cévennes National Park, the Cévennes Biosphere Reserve (UNESCO), as well as a UNESCO World Heritage Site: Causses and the Cévennes, Mediterranean agro-pastoral Cultural Landscape. The area has been inhabited since 400,000 BCE and has numerous megaliths which were erected beginning around 2500 BCE. As an agriculturally-rich area, but not a suitable location for cities, the Cévennes developed a wide diversity of pastoral systems, including transhumance. The irrigation and road networks put in place in the early Middle Ages for these pastoral systems are still in use today.The name Cévennes comes from the Gaulish Cebenna. As of 1999, there were 165,707 inhabitants in the region, with 20,847 living inside the UNESCO protected zone.: 108 Inhabitants of the region are known as Cévenols, from the adjective Cévenol (fem. Cévenole).The mountain range also gives its name to a meteorological effect when cold air from the Atlantic coast meets warm air of southern winds from the Mediterranean and causes heavy autumnal downpours, often leading to floods. These are called épisodes cévenols. Defining the Cévennes Etymology The origin of the name Cévennes is Celtic, coming from the Gaulish Cebenna, which was Latinized by Julius Caesar to Cevenna. The Cévennes are named Cemmenon (Κέμμενων) in Strabo's Geographica. The word in Gaulish probably meant ridgeline and is related to the Breton word kein meaning back. The -vennes part of the name is likely related to the Gaelic word beinn meaning mountain or hill.There are several popular false etymologies, one of which is that the name is derived for the words seven veins (sept veines in French) which is supposed to be a reference to the seven rivers (veins) flowing through the region. Historical references to the name that predate the French Language itself, preclude this possibility. Another false etymology suggests that the name comes from the Occitan word ceba (also written cebo) which means "onion", which is supposed to reference the layered structure of slate which makes up the mountains. But this is not possible as the Occitan ceba derives from Latin cepa which does not phonetically fit the references to the region in Latin and Greek Literature. Additionally, the suffix -enna, originally Celtic, was brought over into Latin, and was never used for words of Latin origin. Geography Extent In the larger sense, the Cévennes include nine départements : le Tarn, l'Aude, l'Hérault, l'Aveyron, le Gard, la Lozère, l'Ardèche, le Rhône and la Loire. More strictly the Cévennes encompasses the Lozère and the Gard. The Parc national des Cévennes is almost entirely within Lozère.The principal towns and villages of the Cévennes are Alès, Le Vigan, Sumène, Valleraugue, Ganges, Hérault, Saint-Hippolyte-du-Fort, Sauve, Lasalle, Saint-André-de-Valborgne, Saint-Jean-du-Gard, Anduze, Florac, Saint-Germain-de-Calberte, le Pont-de-Montvert, Villefort, Génolhac, Bessèges, Saint-Ambroix, Gagnières, Les Vans, Mende. Description The Cévennes mountains run from southwest (Grandes causses (Causses de Blandas and Larzac) to northeast (Monts du Vivarais), with the highest point being the Mont Lozère (1702m). The Mont Aigoual (1567m) is on the border of two departments. The Loire and Allier flowing towards the Atlantic Ocean, as well as the Ardèche and tributary Chassezac, Cèze, the different rivers Gardons to the Rhône, Vidourle, Hérault and Dourbie that flow to the Mediterranean Sea, have their headwaters in the Cévennes. Cévennes National Park was created in the region in 1970 and the Parc Naturel Régional des Monts d'Ardèche also preserves some of the natural areas. Two canyons are near the region: the Gorges de la Jonte (the Jonte gorge) and the Gorges du Tarn (the Tarn gorge). This is a socio-economic marginal region, while bio-geographically, there is altitudinal stratification and a gradient between the mountainous centre and the mediterranean littoral ecologies. Geology The Cévennes form the south eastern fragment of the Massif Central, separated from the related Montagne Noire by the limestone Causses. The basement rocks of granites and schists were uplifted by the Variscan orogeny forming a discontinuity, with the subsequent erosion infilling the lower voids for much of Permian and Triassic period (280–195 Ma), while changing sea levels added a thick limestone covering, with only the tops of the Cévennes protruding as islands in the Jurassic sea. This in turn was eroded, The Cévennes forms the watershed between the Atlantic and Mediterranean. In late Cretaceous and early Tertiary times further mountain building occurred. The Alpine orogeny lifted and deformed the Alps and the Pyrenees though the Massif Central acted as a rigid block, and the cover rocks remained mostly horizontal. Some have been folded through later faulting at the time of the opening of the western Mediterranean in Tertiary times. The principal rivers of the region have cut deeply into the limestone forming deep gorges: Gorges du Tarn, Gorges de la Jonte, Lot, Gorges de l'Ardèche, Cèze etc. Population and history Prehistory Transhumance is most likely the beginning of human activity in the Cévennes: 23 but little trace has been found of humans from the Paleolithic era except in the southern portion around Ganges and Saint-Hippolyte-du-Fort which contains a large quantity of caves rich with archeological evidence such as "La Roque Aynier" (Ganges), and "Baume Dolente" (Vebron) which suggest the presence of Magdalenian peoples (17,000–12,000 BCE).: 25 By the Neolithic epoch, which lasted from about 12,000 BCE to around 2,300 BCE in France (Bronze Age in France), transhumance and hunting were prevalent throughout the entire Cévennes with developments such as pottery moving from south to north in the region. Sheep were common in Mediterranean France before 7000 BCE: 23 and numerous prehistoric pots and tools have been recovered dating from as early as 4000 BCE. Around this time many Megalithic constructions such as stone circles, dolmen, and menhirs appeared in the area, with the second largest megalithic site in Europe, the stone rows of Bondons, being created around 3,000–2,500 BCE, and important sites such as the stone circles around Blandas in the south appearing between 3,500–2,500 BCE. Ancient The Celts arrived in the area sometime in the Iron Age between 800–400 BCE, and most of what is known about their presence in the area is from Latin historians. In the 3rd century BCE, the Arverne Confederation was formed of several tribes who used the Cévennes as a defensive feature to prevent the Romans from taking their territories. By the time the Romans successfully conquered the area in 121 BC, several tribes of celtic Gauls were living around the Cévennes: the Ruteni in the west, the Gabali in the north, the Volcae Arecomici in the south, the Helvii in the southeast and the Vellavi in the northeast. The Volcae Arecomici voluntarily surrendered their territory to the Romans, and the Arverni gave up much territory in a treaty that nevertheless preserved their independence. Under Roman control, Le Vigan was part of the Roman "Provincia," (hence Provence) called Gallia Narbonensis. Julius Caesar crossed the Cévennes mountains in the winter of 52 BCE, having his soldiers clear paths in up to six feet of snow, to attack the Averne Confederation.: 231 The Visigoths took control of the western half of Gallia Narbonensis in 462 CE, a part known as Septimania which included Le Vigan, and they retained control despite attempts in 586 and 589 BCE when the Frankish, Merovingian King Guntram attempted to conquer the area from the north. Middle Ages In 587 the region came under Catholic rule with the conversion of the Visigoth king Reccared I. In 719, the Moor Al-Samh conquered Septimania as part of the Umayyad invasion of Gaul and the Franks struggled to take it back over the next several decades. By 780, Charlemagne had conquered the entire territory. The "Desert" period and the Camisards War French Protestants, also called the Huguenots, were established in the Cévennes by the beginning of the 16th century. They were often persecuted and lacked the freedom to worship openly, so they kept away from cities. They worshiped in deserted wilderness areas: forests, caves, and gullies. The Edict of Nantes in 1598 gave some relief and freedom of worship to Protestants but also concentrated the power of the Catholic Church in France.The Edict of Fontainebleau, on October 1685, revoked the Edict of Nantes, and forbade Protestant worship services. It called for the destruction of temples, exiling pastors, and forced Catholic instruction on the children. The borders were closed in response to the exodus of Huguenots from the area and the resulting economic losses. The Huguenots who stayed resisted and, known as Camisards in the Cévennes, they took up arms to fight for their religious freedom. As many as 3,000 Protestants fought against 30,000 royal troops from 1702 till 1704. Sporadic fighting continued until 1715. The Edict of Versailles in 1787, and the French Revolution and the Declaration of the Rights of Man and of the Citizen in 1789, finally brought a political solution to the struggles and gave non-Catholics the right to practice their religion openly. Modern In the 21st century, the region still has a large community of French Protestants. They identify as Huguenots, descendants of peoples who have inhabited the mountains since before the 16th century. During the reign of Louis XIV, much of the Huguenot population fled France, particularly following the Revocation of the Edict of Nantes in 1685. The Protestant community in the Cévennes largely remained in place, protected from attack by the hilly terrain. This area became a refuge from persecution for other Huguenots during the time. In 1702, this Huguenot population, dubbed the Camisards, rose up against the monarchy to protect their religious freedom. The two sides agreed to peace in 1715, which enabled the local Protestant Huguenot population to continue living in the Cévennes. Their descendants have continued to live there to the present day. During World War II, a network of families in the Cévennes sheltered a number of Jews from capture by the Nazis. These efforts, organized by local Protestant pastors, ultimately protected hundreds from capture and likely death. Popular culture Vincent d'Indy, a composer of Ardèche origin, wrote the Symphonie Cévenole (known in English as his Symphony on a French Mountain Air). Robert Louis Stevenson, a Scottish writer, visited the Cévennes in 1878 and wrote Travels with a Donkey in the Cévennes (1879) about his experiences. Transport 3-hour TGV from Paris, 1h30 flight from London (Luton) to Nîmes (Garons), the closest international airport and 3h30 drive from Barcelona. By car A75 Montpellier – Clermont-Ferrand – Paris A9 (la Languedocienne) Barcelona (Espagne) – Montpellier Tourism The Corniche des Cévennes (the D 907) is a spectacular road between St-Jean-Gard and Florac. It was constructed at the beginning of the 18th century to enable the movement of Louis XIV's troops during his conflict with the Camisards. References External links , by Sabine Baring-Gould Regordane Info – The independent portal for The Regordane Way or St Gilles Trail Archived 2019-05-28 at the Wayback Machine (in English and French) Cévennes mediterranenan tourism Cévennes tourism	country	{ "answer_start": [ 129 ], "text": [ "France" ] }
The Cévennes ( say-VEN, French: [sevɛn] (listen); Occitan: Cevenas) is a cultural region and range of mountains in south-central France, on the south-east edge of the Massif Central. It covers parts of the départements of Ardèche, Gard, Hérault and Lozère. Rich in geographical, natural, and cultural significance, portions of the region are protected within the Cévennes National Park, the Cévennes Biosphere Reserve (UNESCO), as well as a UNESCO World Heritage Site: Causses and the Cévennes, Mediterranean agro-pastoral Cultural Landscape. The area has been inhabited since 400,000 BCE and has numerous megaliths which were erected beginning around 2500 BCE. As an agriculturally-rich area, but not a suitable location for cities, the Cévennes developed a wide diversity of pastoral systems, including transhumance. The irrigation and road networks put in place in the early Middle Ages for these pastoral systems are still in use today.The name Cévennes comes from the Gaulish Cebenna. As of 1999, there were 165,707 inhabitants in the region, with 20,847 living inside the UNESCO protected zone.: 108 Inhabitants of the region are known as Cévenols, from the adjective Cévenol (fem. Cévenole).The mountain range also gives its name to a meteorological effect when cold air from the Atlantic coast meets warm air of southern winds from the Mediterranean and causes heavy autumnal downpours, often leading to floods. These are called épisodes cévenols. Defining the Cévennes Etymology The origin of the name Cévennes is Celtic, coming from the Gaulish Cebenna, which was Latinized by Julius Caesar to Cevenna. The Cévennes are named Cemmenon (Κέμμενων) in Strabo's Geographica. The word in Gaulish probably meant ridgeline and is related to the Breton word kein meaning back. The -vennes part of the name is likely related to the Gaelic word beinn meaning mountain or hill.There are several popular false etymologies, one of which is that the name is derived for the words seven veins (sept veines in French) which is supposed to be a reference to the seven rivers (veins) flowing through the region. Historical references to the name that predate the French Language itself, preclude this possibility. Another false etymology suggests that the name comes from the Occitan word ceba (also written cebo) which means "onion", which is supposed to reference the layered structure of slate which makes up the mountains. But this is not possible as the Occitan ceba derives from Latin cepa which does not phonetically fit the references to the region in Latin and Greek Literature. Additionally, the suffix -enna, originally Celtic, was brought over into Latin, and was never used for words of Latin origin. Geography Extent In the larger sense, the Cévennes include nine départements : le Tarn, l'Aude, l'Hérault, l'Aveyron, le Gard, la Lozère, l'Ardèche, le Rhône and la Loire. More strictly the Cévennes encompasses the Lozère and the Gard. The Parc national des Cévennes is almost entirely within Lozère.The principal towns and villages of the Cévennes are Alès, Le Vigan, Sumène, Valleraugue, Ganges, Hérault, Saint-Hippolyte-du-Fort, Sauve, Lasalle, Saint-André-de-Valborgne, Saint-Jean-du-Gard, Anduze, Florac, Saint-Germain-de-Calberte, le Pont-de-Montvert, Villefort, Génolhac, Bessèges, Saint-Ambroix, Gagnières, Les Vans, Mende. Description The Cévennes mountains run from southwest (Grandes causses (Causses de Blandas and Larzac) to northeast (Monts du Vivarais), with the highest point being the Mont Lozère (1702m). The Mont Aigoual (1567m) is on the border of two departments. The Loire and Allier flowing towards the Atlantic Ocean, as well as the Ardèche and tributary Chassezac, Cèze, the different rivers Gardons to the Rhône, Vidourle, Hérault and Dourbie that flow to the Mediterranean Sea, have their headwaters in the Cévennes. Cévennes National Park was created in the region in 1970 and the Parc Naturel Régional des Monts d'Ardèche also preserves some of the natural areas. Two canyons are near the region: the Gorges de la Jonte (the Jonte gorge) and the Gorges du Tarn (the Tarn gorge). This is a socio-economic marginal region, while bio-geographically, there is altitudinal stratification and a gradient between the mountainous centre and the mediterranean littoral ecologies. Geology The Cévennes form the south eastern fragment of the Massif Central, separated from the related Montagne Noire by the limestone Causses. The basement rocks of granites and schists were uplifted by the Variscan orogeny forming a discontinuity, with the subsequent erosion infilling the lower voids for much of Permian and Triassic period (280–195 Ma), while changing sea levels added a thick limestone covering, with only the tops of the Cévennes protruding as islands in the Jurassic sea. This in turn was eroded, The Cévennes forms the watershed between the Atlantic and Mediterranean. In late Cretaceous and early Tertiary times further mountain building occurred. The Alpine orogeny lifted and deformed the Alps and the Pyrenees though the Massif Central acted as a rigid block, and the cover rocks remained mostly horizontal. Some have been folded through later faulting at the time of the opening of the western Mediterranean in Tertiary times. The principal rivers of the region have cut deeply into the limestone forming deep gorges: Gorges du Tarn, Gorges de la Jonte, Lot, Gorges de l'Ardèche, Cèze etc. Population and history Prehistory Transhumance is most likely the beginning of human activity in the Cévennes: 23 but little trace has been found of humans from the Paleolithic era except in the southern portion around Ganges and Saint-Hippolyte-du-Fort which contains a large quantity of caves rich with archeological evidence such as "La Roque Aynier" (Ganges), and "Baume Dolente" (Vebron) which suggest the presence of Magdalenian peoples (17,000–12,000 BCE).: 25 By the Neolithic epoch, which lasted from about 12,000 BCE to around 2,300 BCE in France (Bronze Age in France), transhumance and hunting were prevalent throughout the entire Cévennes with developments such as pottery moving from south to north in the region. Sheep were common in Mediterranean France before 7000 BCE: 23 and numerous prehistoric pots and tools have been recovered dating from as early as 4000 BCE. Around this time many Megalithic constructions such as stone circles, dolmen, and menhirs appeared in the area, with the second largest megalithic site in Europe, the stone rows of Bondons, being created around 3,000–2,500 BCE, and important sites such as the stone circles around Blandas in the south appearing between 3,500–2,500 BCE. Ancient The Celts arrived in the area sometime in the Iron Age between 800–400 BCE, and most of what is known about their presence in the area is from Latin historians. In the 3rd century BCE, the Arverne Confederation was formed of several tribes who used the Cévennes as a defensive feature to prevent the Romans from taking their territories. By the time the Romans successfully conquered the area in 121 BC, several tribes of celtic Gauls were living around the Cévennes: the Ruteni in the west, the Gabali in the north, the Volcae Arecomici in the south, the Helvii in the southeast and the Vellavi in the northeast. The Volcae Arecomici voluntarily surrendered their territory to the Romans, and the Arverni gave up much territory in a treaty that nevertheless preserved their independence. Under Roman control, Le Vigan was part of the Roman "Provincia," (hence Provence) called Gallia Narbonensis. Julius Caesar crossed the Cévennes mountains in the winter of 52 BCE, having his soldiers clear paths in up to six feet of snow, to attack the Averne Confederation.: 231 The Visigoths took control of the western half of Gallia Narbonensis in 462 CE, a part known as Septimania which included Le Vigan, and they retained control despite attempts in 586 and 589 BCE when the Frankish, Merovingian King Guntram attempted to conquer the area from the north. Middle Ages In 587 the region came under Catholic rule with the conversion of the Visigoth king Reccared I. In 719, the Moor Al-Samh conquered Septimania as part of the Umayyad invasion of Gaul and the Franks struggled to take it back over the next several decades. By 780, Charlemagne had conquered the entire territory. The "Desert" period and the Camisards War French Protestants, also called the Huguenots, were established in the Cévennes by the beginning of the 16th century. They were often persecuted and lacked the freedom to worship openly, so they kept away from cities. They worshiped in deserted wilderness areas: forests, caves, and gullies. The Edict of Nantes in 1598 gave some relief and freedom of worship to Protestants but also concentrated the power of the Catholic Church in France.The Edict of Fontainebleau, on October 1685, revoked the Edict of Nantes, and forbade Protestant worship services. It called for the destruction of temples, exiling pastors, and forced Catholic instruction on the children. The borders were closed in response to the exodus of Huguenots from the area and the resulting economic losses. The Huguenots who stayed resisted and, known as Camisards in the Cévennes, they took up arms to fight for their religious freedom. As many as 3,000 Protestants fought against 30,000 royal troops from 1702 till 1704. Sporadic fighting continued until 1715. The Edict of Versailles in 1787, and the French Revolution and the Declaration of the Rights of Man and of the Citizen in 1789, finally brought a political solution to the struggles and gave non-Catholics the right to practice their religion openly. Modern In the 21st century, the region still has a large community of French Protestants. They identify as Huguenots, descendants of peoples who have inhabited the mountains since before the 16th century. During the reign of Louis XIV, much of the Huguenot population fled France, particularly following the Revocation of the Edict of Nantes in 1685. The Protestant community in the Cévennes largely remained in place, protected from attack by the hilly terrain. This area became a refuge from persecution for other Huguenots during the time. In 1702, this Huguenot population, dubbed the Camisards, rose up against the monarchy to protect their religious freedom. The two sides agreed to peace in 1715, which enabled the local Protestant Huguenot population to continue living in the Cévennes. Their descendants have continued to live there to the present day. During World War II, a network of families in the Cévennes sheltered a number of Jews from capture by the Nazis. These efforts, organized by local Protestant pastors, ultimately protected hundreds from capture and likely death. Popular culture Vincent d'Indy, a composer of Ardèche origin, wrote the Symphonie Cévenole (known in English as his Symphony on a French Mountain Air). Robert Louis Stevenson, a Scottish writer, visited the Cévennes in 1878 and wrote Travels with a Donkey in the Cévennes (1879) about his experiences. Transport 3-hour TGV from Paris, 1h30 flight from London (Luton) to Nîmes (Garons), the closest international airport and 3h30 drive from Barcelona. By car A75 Montpellier – Clermont-Ferrand – Paris A9 (la Languedocienne) Barcelona (Espagne) – Montpellier Tourism The Corniche des Cévennes (the D 907) is a spectacular road between St-Jean-Gard and Florac. It was constructed at the beginning of the 18th century to enable the movement of Louis XIV's troops during his conflict with the Camisards. References External links , by Sabine Baring-Gould Regordane Info – The independent portal for The Regordane Way or St Gilles Trail Archived 2019-05-28 at the Wayback Machine (in English and French) Cévennes mediterranenan tourism Cévennes tourism	instance of	{ "answer_start": [ 1203 ], "text": [ "mountain range" ] }
The Cévennes ( say-VEN, French: [sevɛn] (listen); Occitan: Cevenas) is a cultural region and range of mountains in south-central France, on the south-east edge of the Massif Central. It covers parts of the départements of Ardèche, Gard, Hérault and Lozère. Rich in geographical, natural, and cultural significance, portions of the region are protected within the Cévennes National Park, the Cévennes Biosphere Reserve (UNESCO), as well as a UNESCO World Heritage Site: Causses and the Cévennes, Mediterranean agro-pastoral Cultural Landscape. The area has been inhabited since 400,000 BCE and has numerous megaliths which were erected beginning around 2500 BCE. As an agriculturally-rich area, but not a suitable location for cities, the Cévennes developed a wide diversity of pastoral systems, including transhumance. The irrigation and road networks put in place in the early Middle Ages for these pastoral systems are still in use today.The name Cévennes comes from the Gaulish Cebenna. As of 1999, there were 165,707 inhabitants in the region, with 20,847 living inside the UNESCO protected zone.: 108 Inhabitants of the region are known as Cévenols, from the adjective Cévenol (fem. Cévenole).The mountain range also gives its name to a meteorological effect when cold air from the Atlantic coast meets warm air of southern winds from the Mediterranean and causes heavy autumnal downpours, often leading to floods. These are called épisodes cévenols. Defining the Cévennes Etymology The origin of the name Cévennes is Celtic, coming from the Gaulish Cebenna, which was Latinized by Julius Caesar to Cevenna. The Cévennes are named Cemmenon (Κέμμενων) in Strabo's Geographica. The word in Gaulish probably meant ridgeline and is related to the Breton word kein meaning back. The -vennes part of the name is likely related to the Gaelic word beinn meaning mountain or hill.There are several popular false etymologies, one of which is that the name is derived for the words seven veins (sept veines in French) which is supposed to be a reference to the seven rivers (veins) flowing through the region. Historical references to the name that predate the French Language itself, preclude this possibility. Another false etymology suggests that the name comes from the Occitan word ceba (also written cebo) which means "onion", which is supposed to reference the layered structure of slate which makes up the mountains. But this is not possible as the Occitan ceba derives from Latin cepa which does not phonetically fit the references to the region in Latin and Greek Literature. Additionally, the suffix -enna, originally Celtic, was brought over into Latin, and was never used for words of Latin origin. Geography Extent In the larger sense, the Cévennes include nine départements : le Tarn, l'Aude, l'Hérault, l'Aveyron, le Gard, la Lozère, l'Ardèche, le Rhône and la Loire. More strictly the Cévennes encompasses the Lozère and the Gard. The Parc national des Cévennes is almost entirely within Lozère.The principal towns and villages of the Cévennes are Alès, Le Vigan, Sumène, Valleraugue, Ganges, Hérault, Saint-Hippolyte-du-Fort, Sauve, Lasalle, Saint-André-de-Valborgne, Saint-Jean-du-Gard, Anduze, Florac, Saint-Germain-de-Calberte, le Pont-de-Montvert, Villefort, Génolhac, Bessèges, Saint-Ambroix, Gagnières, Les Vans, Mende. Description The Cévennes mountains run from southwest (Grandes causses (Causses de Blandas and Larzac) to northeast (Monts du Vivarais), with the highest point being the Mont Lozère (1702m). The Mont Aigoual (1567m) is on the border of two departments. The Loire and Allier flowing towards the Atlantic Ocean, as well as the Ardèche and tributary Chassezac, Cèze, the different rivers Gardons to the Rhône, Vidourle, Hérault and Dourbie that flow to the Mediterranean Sea, have their headwaters in the Cévennes. Cévennes National Park was created in the region in 1970 and the Parc Naturel Régional des Monts d'Ardèche also preserves some of the natural areas. Two canyons are near the region: the Gorges de la Jonte (the Jonte gorge) and the Gorges du Tarn (the Tarn gorge). This is a socio-economic marginal region, while bio-geographically, there is altitudinal stratification and a gradient between the mountainous centre and the mediterranean littoral ecologies. Geology The Cévennes form the south eastern fragment of the Massif Central, separated from the related Montagne Noire by the limestone Causses. The basement rocks of granites and schists were uplifted by the Variscan orogeny forming a discontinuity, with the subsequent erosion infilling the lower voids for much of Permian and Triassic period (280–195 Ma), while changing sea levels added a thick limestone covering, with only the tops of the Cévennes protruding as islands in the Jurassic sea. This in turn was eroded, The Cévennes forms the watershed between the Atlantic and Mediterranean. In late Cretaceous and early Tertiary times further mountain building occurred. The Alpine orogeny lifted and deformed the Alps and the Pyrenees though the Massif Central acted as a rigid block, and the cover rocks remained mostly horizontal. Some have been folded through later faulting at the time of the opening of the western Mediterranean in Tertiary times. The principal rivers of the region have cut deeply into the limestone forming deep gorges: Gorges du Tarn, Gorges de la Jonte, Lot, Gorges de l'Ardèche, Cèze etc. Population and history Prehistory Transhumance is most likely the beginning of human activity in the Cévennes: 23 but little trace has been found of humans from the Paleolithic era except in the southern portion around Ganges and Saint-Hippolyte-du-Fort which contains a large quantity of caves rich with archeological evidence such as "La Roque Aynier" (Ganges), and "Baume Dolente" (Vebron) which suggest the presence of Magdalenian peoples (17,000–12,000 BCE).: 25 By the Neolithic epoch, which lasted from about 12,000 BCE to around 2,300 BCE in France (Bronze Age in France), transhumance and hunting were prevalent throughout the entire Cévennes with developments such as pottery moving from south to north in the region. Sheep were common in Mediterranean France before 7000 BCE: 23 and numerous prehistoric pots and tools have been recovered dating from as early as 4000 BCE. Around this time many Megalithic constructions such as stone circles, dolmen, and menhirs appeared in the area, with the second largest megalithic site in Europe, the stone rows of Bondons, being created around 3,000–2,500 BCE, and important sites such as the stone circles around Blandas in the south appearing between 3,500–2,500 BCE. Ancient The Celts arrived in the area sometime in the Iron Age between 800–400 BCE, and most of what is known about their presence in the area is from Latin historians. In the 3rd century BCE, the Arverne Confederation was formed of several tribes who used the Cévennes as a defensive feature to prevent the Romans from taking their territories. By the time the Romans successfully conquered the area in 121 BC, several tribes of celtic Gauls were living around the Cévennes: the Ruteni in the west, the Gabali in the north, the Volcae Arecomici in the south, the Helvii in the southeast and the Vellavi in the northeast. The Volcae Arecomici voluntarily surrendered their territory to the Romans, and the Arverni gave up much territory in a treaty that nevertheless preserved their independence. Under Roman control, Le Vigan was part of the Roman "Provincia," (hence Provence) called Gallia Narbonensis. Julius Caesar crossed the Cévennes mountains in the winter of 52 BCE, having his soldiers clear paths in up to six feet of snow, to attack the Averne Confederation.: 231 The Visigoths took control of the western half of Gallia Narbonensis in 462 CE, a part known as Septimania which included Le Vigan, and they retained control despite attempts in 586 and 589 BCE when the Frankish, Merovingian King Guntram attempted to conquer the area from the north. Middle Ages In 587 the region came under Catholic rule with the conversion of the Visigoth king Reccared I. In 719, the Moor Al-Samh conquered Septimania as part of the Umayyad invasion of Gaul and the Franks struggled to take it back over the next several decades. By 780, Charlemagne had conquered the entire territory. The "Desert" period and the Camisards War French Protestants, also called the Huguenots, were established in the Cévennes by the beginning of the 16th century. They were often persecuted and lacked the freedom to worship openly, so they kept away from cities. They worshiped in deserted wilderness areas: forests, caves, and gullies. The Edict of Nantes in 1598 gave some relief and freedom of worship to Protestants but also concentrated the power of the Catholic Church in France.The Edict of Fontainebleau, on October 1685, revoked the Edict of Nantes, and forbade Protestant worship services. It called for the destruction of temples, exiling pastors, and forced Catholic instruction on the children. The borders were closed in response to the exodus of Huguenots from the area and the resulting economic losses. The Huguenots who stayed resisted and, known as Camisards in the Cévennes, they took up arms to fight for their religious freedom. As many as 3,000 Protestants fought against 30,000 royal troops from 1702 till 1704. Sporadic fighting continued until 1715. The Edict of Versailles in 1787, and the French Revolution and the Declaration of the Rights of Man and of the Citizen in 1789, finally brought a political solution to the struggles and gave non-Catholics the right to practice their religion openly. Modern In the 21st century, the region still has a large community of French Protestants. They identify as Huguenots, descendants of peoples who have inhabited the mountains since before the 16th century. During the reign of Louis XIV, much of the Huguenot population fled France, particularly following the Revocation of the Edict of Nantes in 1685. The Protestant community in the Cévennes largely remained in place, protected from attack by the hilly terrain. This area became a refuge from persecution for other Huguenots during the time. In 1702, this Huguenot population, dubbed the Camisards, rose up against the monarchy to protect their religious freedom. The two sides agreed to peace in 1715, which enabled the local Protestant Huguenot population to continue living in the Cévennes. Their descendants have continued to live there to the present day. During World War II, a network of families in the Cévennes sheltered a number of Jews from capture by the Nazis. These efforts, organized by local Protestant pastors, ultimately protected hundreds from capture and likely death. Popular culture Vincent d'Indy, a composer of Ardèche origin, wrote the Symphonie Cévenole (known in English as his Symphony on a French Mountain Air). Robert Louis Stevenson, a Scottish writer, visited the Cévennes in 1878 and wrote Travels with a Donkey in the Cévennes (1879) about his experiences. Transport 3-hour TGV from Paris, 1h30 flight from London (Luton) to Nîmes (Garons), the closest international airport and 3h30 drive from Barcelona. By car A75 Montpellier – Clermont-Ferrand – Paris A9 (la Languedocienne) Barcelona (Espagne) – Montpellier Tourism The Corniche des Cévennes (the D 907) is a spectacular road between St-Jean-Gard and Florac. It was constructed at the beginning of the 18th century to enable the movement of Louis XIV's troops during his conflict with the Camisards. References External links , by Sabine Baring-Gould Regordane Info – The independent portal for The Regordane Way or St Gilles Trail Archived 2019-05-28 at the Wayback Machine (in English and French) Cévennes mediterranenan tourism Cévennes tourism	Commons category	{ "answer_start": [ 4 ], "text": [ "Cévennes" ] }
The Cévennes ( say-VEN, French: [sevɛn] (listen); Occitan: Cevenas) is a cultural region and range of mountains in south-central France, on the south-east edge of the Massif Central. It covers parts of the départements of Ardèche, Gard, Hérault and Lozère. Rich in geographical, natural, and cultural significance, portions of the region are protected within the Cévennes National Park, the Cévennes Biosphere Reserve (UNESCO), as well as a UNESCO World Heritage Site: Causses and the Cévennes, Mediterranean agro-pastoral Cultural Landscape. The area has been inhabited since 400,000 BCE and has numerous megaliths which were erected beginning around 2500 BCE. As an agriculturally-rich area, but not a suitable location for cities, the Cévennes developed a wide diversity of pastoral systems, including transhumance. The irrigation and road networks put in place in the early Middle Ages for these pastoral systems are still in use today.The name Cévennes comes from the Gaulish Cebenna. As of 1999, there were 165,707 inhabitants in the region, with 20,847 living inside the UNESCO protected zone.: 108 Inhabitants of the region are known as Cévenols, from the adjective Cévenol (fem. Cévenole).The mountain range also gives its name to a meteorological effect when cold air from the Atlantic coast meets warm air of southern winds from the Mediterranean and causes heavy autumnal downpours, often leading to floods. These are called épisodes cévenols. Defining the Cévennes Etymology The origin of the name Cévennes is Celtic, coming from the Gaulish Cebenna, which was Latinized by Julius Caesar to Cevenna. The Cévennes are named Cemmenon (Κέμμενων) in Strabo's Geographica. The word in Gaulish probably meant ridgeline and is related to the Breton word kein meaning back. The -vennes part of the name is likely related to the Gaelic word beinn meaning mountain or hill.There are several popular false etymologies, one of which is that the name is derived for the words seven veins (sept veines in French) which is supposed to be a reference to the seven rivers (veins) flowing through the region. Historical references to the name that predate the French Language itself, preclude this possibility. Another false etymology suggests that the name comes from the Occitan word ceba (also written cebo) which means "onion", which is supposed to reference the layered structure of slate which makes up the mountains. But this is not possible as the Occitan ceba derives from Latin cepa which does not phonetically fit the references to the region in Latin and Greek Literature. Additionally, the suffix -enna, originally Celtic, was brought over into Latin, and was never used for words of Latin origin. Geography Extent In the larger sense, the Cévennes include nine départements : le Tarn, l'Aude, l'Hérault, l'Aveyron, le Gard, la Lozère, l'Ardèche, le Rhône and la Loire. More strictly the Cévennes encompasses the Lozère and the Gard. The Parc national des Cévennes is almost entirely within Lozère.The principal towns and villages of the Cévennes are Alès, Le Vigan, Sumène, Valleraugue, Ganges, Hérault, Saint-Hippolyte-du-Fort, Sauve, Lasalle, Saint-André-de-Valborgne, Saint-Jean-du-Gard, Anduze, Florac, Saint-Germain-de-Calberte, le Pont-de-Montvert, Villefort, Génolhac, Bessèges, Saint-Ambroix, Gagnières, Les Vans, Mende. Description The Cévennes mountains run from southwest (Grandes causses (Causses de Blandas and Larzac) to northeast (Monts du Vivarais), with the highest point being the Mont Lozère (1702m). The Mont Aigoual (1567m) is on the border of two departments. The Loire and Allier flowing towards the Atlantic Ocean, as well as the Ardèche and tributary Chassezac, Cèze, the different rivers Gardons to the Rhône, Vidourle, Hérault and Dourbie that flow to the Mediterranean Sea, have their headwaters in the Cévennes. Cévennes National Park was created in the region in 1970 and the Parc Naturel Régional des Monts d'Ardèche also preserves some of the natural areas. Two canyons are near the region: the Gorges de la Jonte (the Jonte gorge) and the Gorges du Tarn (the Tarn gorge). This is a socio-economic marginal region, while bio-geographically, there is altitudinal stratification and a gradient between the mountainous centre and the mediterranean littoral ecologies. Geology The Cévennes form the south eastern fragment of the Massif Central, separated from the related Montagne Noire by the limestone Causses. The basement rocks of granites and schists were uplifted by the Variscan orogeny forming a discontinuity, with the subsequent erosion infilling the lower voids for much of Permian and Triassic period (280–195 Ma), while changing sea levels added a thick limestone covering, with only the tops of the Cévennes protruding as islands in the Jurassic sea. This in turn was eroded, The Cévennes forms the watershed between the Atlantic and Mediterranean. In late Cretaceous and early Tertiary times further mountain building occurred. The Alpine orogeny lifted and deformed the Alps and the Pyrenees though the Massif Central acted as a rigid block, and the cover rocks remained mostly horizontal. Some have been folded through later faulting at the time of the opening of the western Mediterranean in Tertiary times. The principal rivers of the region have cut deeply into the limestone forming deep gorges: Gorges du Tarn, Gorges de la Jonte, Lot, Gorges de l'Ardèche, Cèze etc. Population and history Prehistory Transhumance is most likely the beginning of human activity in the Cévennes: 23 but little trace has been found of humans from the Paleolithic era except in the southern portion around Ganges and Saint-Hippolyte-du-Fort which contains a large quantity of caves rich with archeological evidence such as "La Roque Aynier" (Ganges), and "Baume Dolente" (Vebron) which suggest the presence of Magdalenian peoples (17,000–12,000 BCE).: 25 By the Neolithic epoch, which lasted from about 12,000 BCE to around 2,300 BCE in France (Bronze Age in France), transhumance and hunting were prevalent throughout the entire Cévennes with developments such as pottery moving from south to north in the region. Sheep were common in Mediterranean France before 7000 BCE: 23 and numerous prehistoric pots and tools have been recovered dating from as early as 4000 BCE. Around this time many Megalithic constructions such as stone circles, dolmen, and menhirs appeared in the area, with the second largest megalithic site in Europe, the stone rows of Bondons, being created around 3,000–2,500 BCE, and important sites such as the stone circles around Blandas in the south appearing between 3,500–2,500 BCE. Ancient The Celts arrived in the area sometime in the Iron Age between 800–400 BCE, and most of what is known about their presence in the area is from Latin historians. In the 3rd century BCE, the Arverne Confederation was formed of several tribes who used the Cévennes as a defensive feature to prevent the Romans from taking their territories. By the time the Romans successfully conquered the area in 121 BC, several tribes of celtic Gauls were living around the Cévennes: the Ruteni in the west, the Gabali in the north, the Volcae Arecomici in the south, the Helvii in the southeast and the Vellavi in the northeast. The Volcae Arecomici voluntarily surrendered their territory to the Romans, and the Arverni gave up much territory in a treaty that nevertheless preserved their independence. Under Roman control, Le Vigan was part of the Roman "Provincia," (hence Provence) called Gallia Narbonensis. Julius Caesar crossed the Cévennes mountains in the winter of 52 BCE, having his soldiers clear paths in up to six feet of snow, to attack the Averne Confederation.: 231 The Visigoths took control of the western half of Gallia Narbonensis in 462 CE, a part known as Septimania which included Le Vigan, and they retained control despite attempts in 586 and 589 BCE when the Frankish, Merovingian King Guntram attempted to conquer the area from the north. Middle Ages In 587 the region came under Catholic rule with the conversion of the Visigoth king Reccared I. In 719, the Moor Al-Samh conquered Septimania as part of the Umayyad invasion of Gaul and the Franks struggled to take it back over the next several decades. By 780, Charlemagne had conquered the entire territory. The "Desert" period and the Camisards War French Protestants, also called the Huguenots, were established in the Cévennes by the beginning of the 16th century. They were often persecuted and lacked the freedom to worship openly, so they kept away from cities. They worshiped in deserted wilderness areas: forests, caves, and gullies. The Edict of Nantes in 1598 gave some relief and freedom of worship to Protestants but also concentrated the power of the Catholic Church in France.The Edict of Fontainebleau, on October 1685, revoked the Edict of Nantes, and forbade Protestant worship services. It called for the destruction of temples, exiling pastors, and forced Catholic instruction on the children. The borders were closed in response to the exodus of Huguenots from the area and the resulting economic losses. The Huguenots who stayed resisted and, known as Camisards in the Cévennes, they took up arms to fight for their religious freedom. As many as 3,000 Protestants fought against 30,000 royal troops from 1702 till 1704. Sporadic fighting continued until 1715. The Edict of Versailles in 1787, and the French Revolution and the Declaration of the Rights of Man and of the Citizen in 1789, finally brought a political solution to the struggles and gave non-Catholics the right to practice their religion openly. Modern In the 21st century, the region still has a large community of French Protestants. They identify as Huguenots, descendants of peoples who have inhabited the mountains since before the 16th century. During the reign of Louis XIV, much of the Huguenot population fled France, particularly following the Revocation of the Edict of Nantes in 1685. The Protestant community in the Cévennes largely remained in place, protected from attack by the hilly terrain. This area became a refuge from persecution for other Huguenots during the time. In 1702, this Huguenot population, dubbed the Camisards, rose up against the monarchy to protect their religious freedom. The two sides agreed to peace in 1715, which enabled the local Protestant Huguenot population to continue living in the Cévennes. Their descendants have continued to live there to the present day. During World War II, a network of families in the Cévennes sheltered a number of Jews from capture by the Nazis. These efforts, organized by local Protestant pastors, ultimately protected hundreds from capture and likely death. Popular culture Vincent d'Indy, a composer of Ardèche origin, wrote the Symphonie Cévenole (known in English as his Symphony on a French Mountain Air). Robert Louis Stevenson, a Scottish writer, visited the Cévennes in 1878 and wrote Travels with a Donkey in the Cévennes (1879) about his experiences. Transport 3-hour TGV from Paris, 1h30 flight from London (Luton) to Nîmes (Garons), the closest international airport and 3h30 drive from Barcelona. By car A75 Montpellier – Clermont-Ferrand – Paris A9 (la Languedocienne) Barcelona (Espagne) – Montpellier Tourism The Corniche des Cévennes (the D 907) is a spectacular road between St-Jean-Gard and Florac. It was constructed at the beginning of the 18th century to enable the movement of Louis XIV's troops during his conflict with the Camisards. References External links , by Sabine Baring-Gould Regordane Info – The independent portal for The Regordane Way or St Gilles Trail Archived 2019-05-28 at the Wayback Machine (in English and French) Cévennes mediterranenan tourism Cévennes tourism	highest point	{ "answer_start": [ 3513 ], "text": [ "Mont Lozère" ] }
The Cévennes ( say-VEN, French: [sevɛn] (listen); Occitan: Cevenas) is a cultural region and range of mountains in south-central France, on the south-east edge of the Massif Central. It covers parts of the départements of Ardèche, Gard, Hérault and Lozère. Rich in geographical, natural, and cultural significance, portions of the region are protected within the Cévennes National Park, the Cévennes Biosphere Reserve (UNESCO), as well as a UNESCO World Heritage Site: Causses and the Cévennes, Mediterranean agro-pastoral Cultural Landscape. The area has been inhabited since 400,000 BCE and has numerous megaliths which were erected beginning around 2500 BCE. As an agriculturally-rich area, but not a suitable location for cities, the Cévennes developed a wide diversity of pastoral systems, including transhumance. The irrigation and road networks put in place in the early Middle Ages for these pastoral systems are still in use today.The name Cévennes comes from the Gaulish Cebenna. As of 1999, there were 165,707 inhabitants in the region, with 20,847 living inside the UNESCO protected zone.: 108 Inhabitants of the region are known as Cévenols, from the adjective Cévenol (fem. Cévenole).The mountain range also gives its name to a meteorological effect when cold air from the Atlantic coast meets warm air of southern winds from the Mediterranean and causes heavy autumnal downpours, often leading to floods. These are called épisodes cévenols. Defining the Cévennes Etymology The origin of the name Cévennes is Celtic, coming from the Gaulish Cebenna, which was Latinized by Julius Caesar to Cevenna. The Cévennes are named Cemmenon (Κέμμενων) in Strabo's Geographica. The word in Gaulish probably meant ridgeline and is related to the Breton word kein meaning back. The -vennes part of the name is likely related to the Gaelic word beinn meaning mountain or hill.There are several popular false etymologies, one of which is that the name is derived for the words seven veins (sept veines in French) which is supposed to be a reference to the seven rivers (veins) flowing through the region. Historical references to the name that predate the French Language itself, preclude this possibility. Another false etymology suggests that the name comes from the Occitan word ceba (also written cebo) which means "onion", which is supposed to reference the layered structure of slate which makes up the mountains. But this is not possible as the Occitan ceba derives from Latin cepa which does not phonetically fit the references to the region in Latin and Greek Literature. Additionally, the suffix -enna, originally Celtic, was brought over into Latin, and was never used for words of Latin origin. Geography Extent In the larger sense, the Cévennes include nine départements : le Tarn, l'Aude, l'Hérault, l'Aveyron, le Gard, la Lozère, l'Ardèche, le Rhône and la Loire. More strictly the Cévennes encompasses the Lozère and the Gard. The Parc national des Cévennes is almost entirely within Lozère.The principal towns and villages of the Cévennes are Alès, Le Vigan, Sumène, Valleraugue, Ganges, Hérault, Saint-Hippolyte-du-Fort, Sauve, Lasalle, Saint-André-de-Valborgne, Saint-Jean-du-Gard, Anduze, Florac, Saint-Germain-de-Calberte, le Pont-de-Montvert, Villefort, Génolhac, Bessèges, Saint-Ambroix, Gagnières, Les Vans, Mende. Description The Cévennes mountains run from southwest (Grandes causses (Causses de Blandas and Larzac) to northeast (Monts du Vivarais), with the highest point being the Mont Lozère (1702m). The Mont Aigoual (1567m) is on the border of two departments. The Loire and Allier flowing towards the Atlantic Ocean, as well as the Ardèche and tributary Chassezac, Cèze, the different rivers Gardons to the Rhône, Vidourle, Hérault and Dourbie that flow to the Mediterranean Sea, have their headwaters in the Cévennes. Cévennes National Park was created in the region in 1970 and the Parc Naturel Régional des Monts d'Ardèche also preserves some of the natural areas. Two canyons are near the region: the Gorges de la Jonte (the Jonte gorge) and the Gorges du Tarn (the Tarn gorge). This is a socio-economic marginal region, while bio-geographically, there is altitudinal stratification and a gradient between the mountainous centre and the mediterranean littoral ecologies. Geology The Cévennes form the south eastern fragment of the Massif Central, separated from the related Montagne Noire by the limestone Causses. The basement rocks of granites and schists were uplifted by the Variscan orogeny forming a discontinuity, with the subsequent erosion infilling the lower voids for much of Permian and Triassic period (280–195 Ma), while changing sea levels added a thick limestone covering, with only the tops of the Cévennes protruding as islands in the Jurassic sea. This in turn was eroded, The Cévennes forms the watershed between the Atlantic and Mediterranean. In late Cretaceous and early Tertiary times further mountain building occurred. The Alpine orogeny lifted and deformed the Alps and the Pyrenees though the Massif Central acted as a rigid block, and the cover rocks remained mostly horizontal. Some have been folded through later faulting at the time of the opening of the western Mediterranean in Tertiary times. The principal rivers of the region have cut deeply into the limestone forming deep gorges: Gorges du Tarn, Gorges de la Jonte, Lot, Gorges de l'Ardèche, Cèze etc. Population and history Prehistory Transhumance is most likely the beginning of human activity in the Cévennes: 23 but little trace has been found of humans from the Paleolithic era except in the southern portion around Ganges and Saint-Hippolyte-du-Fort which contains a large quantity of caves rich with archeological evidence such as "La Roque Aynier" (Ganges), and "Baume Dolente" (Vebron) which suggest the presence of Magdalenian peoples (17,000–12,000 BCE).: 25 By the Neolithic epoch, which lasted from about 12,000 BCE to around 2,300 BCE in France (Bronze Age in France), transhumance and hunting were prevalent throughout the entire Cévennes with developments such as pottery moving from south to north in the region. Sheep were common in Mediterranean France before 7000 BCE: 23 and numerous prehistoric pots and tools have been recovered dating from as early as 4000 BCE. Around this time many Megalithic constructions such as stone circles, dolmen, and menhirs appeared in the area, with the second largest megalithic site in Europe, the stone rows of Bondons, being created around 3,000–2,500 BCE, and important sites such as the stone circles around Blandas in the south appearing between 3,500–2,500 BCE. Ancient The Celts arrived in the area sometime in the Iron Age between 800–400 BCE, and most of what is known about their presence in the area is from Latin historians. In the 3rd century BCE, the Arverne Confederation was formed of several tribes who used the Cévennes as a defensive feature to prevent the Romans from taking their territories. By the time the Romans successfully conquered the area in 121 BC, several tribes of celtic Gauls were living around the Cévennes: the Ruteni in the west, the Gabali in the north, the Volcae Arecomici in the south, the Helvii in the southeast and the Vellavi in the northeast. The Volcae Arecomici voluntarily surrendered their territory to the Romans, and the Arverni gave up much territory in a treaty that nevertheless preserved their independence. Under Roman control, Le Vigan was part of the Roman "Provincia," (hence Provence) called Gallia Narbonensis. Julius Caesar crossed the Cévennes mountains in the winter of 52 BCE, having his soldiers clear paths in up to six feet of snow, to attack the Averne Confederation.: 231 The Visigoths took control of the western half of Gallia Narbonensis in 462 CE, a part known as Septimania which included Le Vigan, and they retained control despite attempts in 586 and 589 BCE when the Frankish, Merovingian King Guntram attempted to conquer the area from the north. Middle Ages In 587 the region came under Catholic rule with the conversion of the Visigoth king Reccared I. In 719, the Moor Al-Samh conquered Septimania as part of the Umayyad invasion of Gaul and the Franks struggled to take it back over the next several decades. By 780, Charlemagne had conquered the entire territory. The "Desert" period and the Camisards War French Protestants, also called the Huguenots, were established in the Cévennes by the beginning of the 16th century. They were often persecuted and lacked the freedom to worship openly, so they kept away from cities. They worshiped in deserted wilderness areas: forests, caves, and gullies. The Edict of Nantes in 1598 gave some relief and freedom of worship to Protestants but also concentrated the power of the Catholic Church in France.The Edict of Fontainebleau, on October 1685, revoked the Edict of Nantes, and forbade Protestant worship services. It called for the destruction of temples, exiling pastors, and forced Catholic instruction on the children. The borders were closed in response to the exodus of Huguenots from the area and the resulting economic losses. The Huguenots who stayed resisted and, known as Camisards in the Cévennes, they took up arms to fight for their religious freedom. As many as 3,000 Protestants fought against 30,000 royal troops from 1702 till 1704. Sporadic fighting continued until 1715. The Edict of Versailles in 1787, and the French Revolution and the Declaration of the Rights of Man and of the Citizen in 1789, finally brought a political solution to the struggles and gave non-Catholics the right to practice their religion openly. Modern In the 21st century, the region still has a large community of French Protestants. They identify as Huguenots, descendants of peoples who have inhabited the mountains since before the 16th century. During the reign of Louis XIV, much of the Huguenot population fled France, particularly following the Revocation of the Edict of Nantes in 1685. The Protestant community in the Cévennes largely remained in place, protected from attack by the hilly terrain. This area became a refuge from persecution for other Huguenots during the time. In 1702, this Huguenot population, dubbed the Camisards, rose up against the monarchy to protect their religious freedom. The two sides agreed to peace in 1715, which enabled the local Protestant Huguenot population to continue living in the Cévennes. Their descendants have continued to live there to the present day. During World War II, a network of families in the Cévennes sheltered a number of Jews from capture by the Nazis. These efforts, organized by local Protestant pastors, ultimately protected hundreds from capture and likely death. Popular culture Vincent d'Indy, a composer of Ardèche origin, wrote the Symphonie Cévenole (known in English as his Symphony on a French Mountain Air). Robert Louis Stevenson, a Scottish writer, visited the Cévennes in 1878 and wrote Travels with a Donkey in the Cévennes (1879) about his experiences. Transport 3-hour TGV from Paris, 1h30 flight from London (Luton) to Nîmes (Garons), the closest international airport and 3h30 drive from Barcelona. By car A75 Montpellier – Clermont-Ferrand – Paris A9 (la Languedocienne) Barcelona (Espagne) – Montpellier Tourism The Corniche des Cévennes (the D 907) is a spectacular road between St-Jean-Gard and Florac. It was constructed at the beginning of the 18th century to enable the movement of Louis XIV's troops during his conflict with the Camisards. References External links , by Sabine Baring-Gould Regordane Info – The independent portal for The Regordane Way or St Gilles Trail Archived 2019-05-28 at the Wayback Machine (in English and French) Cévennes mediterranenan tourism Cévennes tourism	elevation above sea level	{ "answer_start": [ 3526 ], "text": [ "1702" ] }
The Cévennes ( say-VEN, French: [sevɛn] (listen); Occitan: Cevenas) is a cultural region and range of mountains in south-central France, on the south-east edge of the Massif Central. It covers parts of the départements of Ardèche, Gard, Hérault and Lozère. Rich in geographical, natural, and cultural significance, portions of the region are protected within the Cévennes National Park, the Cévennes Biosphere Reserve (UNESCO), as well as a UNESCO World Heritage Site: Causses and the Cévennes, Mediterranean agro-pastoral Cultural Landscape. The area has been inhabited since 400,000 BCE and has numerous megaliths which were erected beginning around 2500 BCE. As an agriculturally-rich area, but not a suitable location for cities, the Cévennes developed a wide diversity of pastoral systems, including transhumance. The irrigation and road networks put in place in the early Middle Ages for these pastoral systems are still in use today.The name Cévennes comes from the Gaulish Cebenna. As of 1999, there were 165,707 inhabitants in the region, with 20,847 living inside the UNESCO protected zone.: 108 Inhabitants of the region are known as Cévenols, from the adjective Cévenol (fem. Cévenole).The mountain range also gives its name to a meteorological effect when cold air from the Atlantic coast meets warm air of southern winds from the Mediterranean and causes heavy autumnal downpours, often leading to floods. These are called épisodes cévenols. Defining the Cévennes Etymology The origin of the name Cévennes is Celtic, coming from the Gaulish Cebenna, which was Latinized by Julius Caesar to Cevenna. The Cévennes are named Cemmenon (Κέμμενων) in Strabo's Geographica. The word in Gaulish probably meant ridgeline and is related to the Breton word kein meaning back. The -vennes part of the name is likely related to the Gaelic word beinn meaning mountain or hill.There are several popular false etymologies, one of which is that the name is derived for the words seven veins (sept veines in French) which is supposed to be a reference to the seven rivers (veins) flowing through the region. Historical references to the name that predate the French Language itself, preclude this possibility. Another false etymology suggests that the name comes from the Occitan word ceba (also written cebo) which means "onion", which is supposed to reference the layered structure of slate which makes up the mountains. But this is not possible as the Occitan ceba derives from Latin cepa which does not phonetically fit the references to the region in Latin and Greek Literature. Additionally, the suffix -enna, originally Celtic, was brought over into Latin, and was never used for words of Latin origin. Geography Extent In the larger sense, the Cévennes include nine départements : le Tarn, l'Aude, l'Hérault, l'Aveyron, le Gard, la Lozère, l'Ardèche, le Rhône and la Loire. More strictly the Cévennes encompasses the Lozère and the Gard. The Parc national des Cévennes is almost entirely within Lozère.The principal towns and villages of the Cévennes are Alès, Le Vigan, Sumène, Valleraugue, Ganges, Hérault, Saint-Hippolyte-du-Fort, Sauve, Lasalle, Saint-André-de-Valborgne, Saint-Jean-du-Gard, Anduze, Florac, Saint-Germain-de-Calberte, le Pont-de-Montvert, Villefort, Génolhac, Bessèges, Saint-Ambroix, Gagnières, Les Vans, Mende. Description The Cévennes mountains run from southwest (Grandes causses (Causses de Blandas and Larzac) to northeast (Monts du Vivarais), with the highest point being the Mont Lozère (1702m). The Mont Aigoual (1567m) is on the border of two departments. The Loire and Allier flowing towards the Atlantic Ocean, as well as the Ardèche and tributary Chassezac, Cèze, the different rivers Gardons to the Rhône, Vidourle, Hérault and Dourbie that flow to the Mediterranean Sea, have their headwaters in the Cévennes. Cévennes National Park was created in the region in 1970 and the Parc Naturel Régional des Monts d'Ardèche also preserves some of the natural areas. Two canyons are near the region: the Gorges de la Jonte (the Jonte gorge) and the Gorges du Tarn (the Tarn gorge). This is a socio-economic marginal region, while bio-geographically, there is altitudinal stratification and a gradient between the mountainous centre and the mediterranean littoral ecologies. Geology The Cévennes form the south eastern fragment of the Massif Central, separated from the related Montagne Noire by the limestone Causses. The basement rocks of granites and schists were uplifted by the Variscan orogeny forming a discontinuity, with the subsequent erosion infilling the lower voids for much of Permian and Triassic period (280–195 Ma), while changing sea levels added a thick limestone covering, with only the tops of the Cévennes protruding as islands in the Jurassic sea. This in turn was eroded, The Cévennes forms the watershed between the Atlantic and Mediterranean. In late Cretaceous and early Tertiary times further mountain building occurred. The Alpine orogeny lifted and deformed the Alps and the Pyrenees though the Massif Central acted as a rigid block, and the cover rocks remained mostly horizontal. Some have been folded through later faulting at the time of the opening of the western Mediterranean in Tertiary times. The principal rivers of the region have cut deeply into the limestone forming deep gorges: Gorges du Tarn, Gorges de la Jonte, Lot, Gorges de l'Ardèche, Cèze etc. Population and history Prehistory Transhumance is most likely the beginning of human activity in the Cévennes: 23 but little trace has been found of humans from the Paleolithic era except in the southern portion around Ganges and Saint-Hippolyte-du-Fort which contains a large quantity of caves rich with archeological evidence such as "La Roque Aynier" (Ganges), and "Baume Dolente" (Vebron) which suggest the presence of Magdalenian peoples (17,000–12,000 BCE).: 25 By the Neolithic epoch, which lasted from about 12,000 BCE to around 2,300 BCE in France (Bronze Age in France), transhumance and hunting were prevalent throughout the entire Cévennes with developments such as pottery moving from south to north in the region. Sheep were common in Mediterranean France before 7000 BCE: 23 and numerous prehistoric pots and tools have been recovered dating from as early as 4000 BCE. Around this time many Megalithic constructions such as stone circles, dolmen, and menhirs appeared in the area, with the second largest megalithic site in Europe, the stone rows of Bondons, being created around 3,000–2,500 BCE, and important sites such as the stone circles around Blandas in the south appearing between 3,500–2,500 BCE. Ancient The Celts arrived in the area sometime in the Iron Age between 800–400 BCE, and most of what is known about their presence in the area is from Latin historians. In the 3rd century BCE, the Arverne Confederation was formed of several tribes who used the Cévennes as a defensive feature to prevent the Romans from taking their territories. By the time the Romans successfully conquered the area in 121 BC, several tribes of celtic Gauls were living around the Cévennes: the Ruteni in the west, the Gabali in the north, the Volcae Arecomici in the south, the Helvii in the southeast and the Vellavi in the northeast. The Volcae Arecomici voluntarily surrendered their territory to the Romans, and the Arverni gave up much territory in a treaty that nevertheless preserved their independence. Under Roman control, Le Vigan was part of the Roman "Provincia," (hence Provence) called Gallia Narbonensis. Julius Caesar crossed the Cévennes mountains in the winter of 52 BCE, having his soldiers clear paths in up to six feet of snow, to attack the Averne Confederation.: 231 The Visigoths took control of the western half of Gallia Narbonensis in 462 CE, a part known as Septimania which included Le Vigan, and they retained control despite attempts in 586 and 589 BCE when the Frankish, Merovingian King Guntram attempted to conquer the area from the north. Middle Ages In 587 the region came under Catholic rule with the conversion of the Visigoth king Reccared I. In 719, the Moor Al-Samh conquered Septimania as part of the Umayyad invasion of Gaul and the Franks struggled to take it back over the next several decades. By 780, Charlemagne had conquered the entire territory. The "Desert" period and the Camisards War French Protestants, also called the Huguenots, were established in the Cévennes by the beginning of the 16th century. They were often persecuted and lacked the freedom to worship openly, so they kept away from cities. They worshiped in deserted wilderness areas: forests, caves, and gullies. The Edict of Nantes in 1598 gave some relief and freedom of worship to Protestants but also concentrated the power of the Catholic Church in France.The Edict of Fontainebleau, on October 1685, revoked the Edict of Nantes, and forbade Protestant worship services. It called for the destruction of temples, exiling pastors, and forced Catholic instruction on the children. The borders were closed in response to the exodus of Huguenots from the area and the resulting economic losses. The Huguenots who stayed resisted and, known as Camisards in the Cévennes, they took up arms to fight for their religious freedom. As many as 3,000 Protestants fought against 30,000 royal troops from 1702 till 1704. Sporadic fighting continued until 1715. The Edict of Versailles in 1787, and the French Revolution and the Declaration of the Rights of Man and of the Citizen in 1789, finally brought a political solution to the struggles and gave non-Catholics the right to practice their religion openly. Modern In the 21st century, the region still has a large community of French Protestants. They identify as Huguenots, descendants of peoples who have inhabited the mountains since before the 16th century. During the reign of Louis XIV, much of the Huguenot population fled France, particularly following the Revocation of the Edict of Nantes in 1685. The Protestant community in the Cévennes largely remained in place, protected from attack by the hilly terrain. This area became a refuge from persecution for other Huguenots during the time. In 1702, this Huguenot population, dubbed the Camisards, rose up against the monarchy to protect their religious freedom. The two sides agreed to peace in 1715, which enabled the local Protestant Huguenot population to continue living in the Cévennes. Their descendants have continued to live there to the present day. During World War II, a network of families in the Cévennes sheltered a number of Jews from capture by the Nazis. These efforts, organized by local Protestant pastors, ultimately protected hundreds from capture and likely death. Popular culture Vincent d'Indy, a composer of Ardèche origin, wrote the Symphonie Cévenole (known in English as his Symphony on a French Mountain Air). Robert Louis Stevenson, a Scottish writer, visited the Cévennes in 1878 and wrote Travels with a Donkey in the Cévennes (1879) about his experiences. Transport 3-hour TGV from Paris, 1h30 flight from London (Luton) to Nîmes (Garons), the closest international airport and 3h30 drive from Barcelona. By car A75 Montpellier – Clermont-Ferrand – Paris A9 (la Languedocienne) Barcelona (Espagne) – Montpellier Tourism The Corniche des Cévennes (the D 907) is a spectacular road between St-Jean-Gard and Florac. It was constructed at the beginning of the 18th century to enable the movement of Louis XIV's troops during his conflict with the Camisards. References External links , by Sabine Baring-Gould Regordane Info – The independent portal for The Regordane Way or St Gilles Trail Archived 2019-05-28 at the Wayback Machine (in English and French) Cévennes mediterranenan tourism Cévennes tourism	mountain range	{ "answer_start": [ 167 ], "text": [ "Massif Central" ] }
State Road 269 (SR 269) is a part of the Indiana State Road that runs through rural Posey County in US state of Indiana. The 0.89 miles (1.43 km) of SR 269 that lie within Indiana serve as a mirror highway. None of the highway is listed on the National Highway System. The whole length is a rural two-lane highway. The highway passes through farmland and woodland properties. Route description SR 269 begins at a rural intersection in Posey County at County Road 330 and Old Dam Road. The route heads southeast away from Harmonie State Park, as a two-lane highway, passing through farmland and woodland. The highway turns due east and heads towards SR 69. SR 269 ends at a 3-way intersection with SR 69.No segment of SR 269 is included as a part of the National Highway System (NHS). The NHS is a network of highways that are identified as being most important for the economy, mobility and defense of the nation. The highway is maintained by the Indiana Department of Transportation (INDOT) like all other state road in the state. The department tracks the traffic volumes along all state highways as a part of its maintenance responsibilities using a metric called average annual daily traffic (AADT). This measurement is a calculation of the traffic level along a segment of roadway for any average day of the year. In 2010, INDOT figured that 100 vehicles and 10 commercial vehicles AADT along the route. Major intersections The entire route is in Lynn Township, Posey County. References == External links ==	instance of	{ "answer_start": [ 1021 ], "text": [ "road" ] }
State Road 269 (SR 269) is a part of the Indiana State Road that runs through rural Posey County in US state of Indiana. The 0.89 miles (1.43 km) of SR 269 that lie within Indiana serve as a mirror highway. None of the highway is listed on the National Highway System. The whole length is a rural two-lane highway. The highway passes through farmland and woodland properties. Route description SR 269 begins at a rural intersection in Posey County at County Road 330 and Old Dam Road. The route heads southeast away from Harmonie State Park, as a two-lane highway, passing through farmland and woodland. The highway turns due east and heads towards SR 69. SR 269 ends at a 3-way intersection with SR 69.No segment of SR 269 is included as a part of the National Highway System (NHS). The NHS is a network of highways that are identified as being most important for the economy, mobility and defense of the nation. The highway is maintained by the Indiana Department of Transportation (INDOT) like all other state road in the state. The department tracks the traffic volumes along all state highways as a part of its maintenance responsibilities using a metric called average annual daily traffic (AADT). This measurement is a calculation of the traffic level along a segment of roadway for any average day of the year. In 2010, INDOT figured that 100 vehicles and 10 commercial vehicles AADT along the route. Major intersections The entire route is in Lynn Township, Posey County. References == External links ==	maintained by	{ "answer_start": [ 955 ], "text": [ "Indiana Department of Transportation" ] }
State Road 269 (SR 269) is a part of the Indiana State Road that runs through rural Posey County in US state of Indiana. The 0.89 miles (1.43 km) of SR 269 that lie within Indiana serve as a mirror highway. None of the highway is listed on the National Highway System. The whole length is a rural two-lane highway. The highway passes through farmland and woodland properties. Route description SR 269 begins at a rural intersection in Posey County at County Road 330 and Old Dam Road. The route heads southeast away from Harmonie State Park, as a two-lane highway, passing through farmland and woodland. The highway turns due east and heads towards SR 69. SR 269 ends at a 3-way intersection with SR 69.No segment of SR 269 is included as a part of the National Highway System (NHS). The NHS is a network of highways that are identified as being most important for the economy, mobility and defense of the nation. The highway is maintained by the Indiana Department of Transportation (INDOT) like all other state road in the state. The department tracks the traffic volumes along all state highways as a part of its maintenance responsibilities using a metric called average annual daily traffic (AADT). This measurement is a calculation of the traffic level along a segment of roadway for any average day of the year. In 2010, INDOT figured that 100 vehicles and 10 commercial vehicles AADT along the route. Major intersections The entire route is in Lynn Township, Posey County. References == External links ==	owned by	{ "answer_start": [ 955 ], "text": [ "Indiana Department of Transportation" ] }
State Road 269 (SR 269) is a part of the Indiana State Road that runs through rural Posey County in US state of Indiana. The 0.89 miles (1.43 km) of SR 269 that lie within Indiana serve as a mirror highway. None of the highway is listed on the National Highway System. The whole length is a rural two-lane highway. The highway passes through farmland and woodland properties. Route description SR 269 begins at a rural intersection in Posey County at County Road 330 and Old Dam Road. The route heads southeast away from Harmonie State Park, as a two-lane highway, passing through farmland and woodland. The highway turns due east and heads towards SR 69. SR 269 ends at a 3-way intersection with SR 69.No segment of SR 269 is included as a part of the National Highway System (NHS). The NHS is a network of highways that are identified as being most important for the economy, mobility and defense of the nation. The highway is maintained by the Indiana Department of Transportation (INDOT) like all other state road in the state. The department tracks the traffic volumes along all state highways as a part of its maintenance responsibilities using a metric called average annual daily traffic (AADT). This measurement is a calculation of the traffic level along a segment of roadway for any average day of the year. In 2010, INDOT figured that 100 vehicles and 10 commercial vehicles AADT along the route. Major intersections The entire route is in Lynn Township, Posey County. References == External links ==	located in the administrative territorial entity	{ "answer_start": [ 41 ], "text": [ "Indiana" ] }
State Road 269 (SR 269) is a part of the Indiana State Road that runs through rural Posey County in US state of Indiana. The 0.89 miles (1.43 km) of SR 269 that lie within Indiana serve as a mirror highway. None of the highway is listed on the National Highway System. The whole length is a rural two-lane highway. The highway passes through farmland and woodland properties. Route description SR 269 begins at a rural intersection in Posey County at County Road 330 and Old Dam Road. The route heads southeast away from Harmonie State Park, as a two-lane highway, passing through farmland and woodland. The highway turns due east and heads towards SR 69. SR 269 ends at a 3-way intersection with SR 69.No segment of SR 269 is included as a part of the National Highway System (NHS). The NHS is a network of highways that are identified as being most important for the economy, mobility and defense of the nation. The highway is maintained by the Indiana Department of Transportation (INDOT) like all other state road in the state. The department tracks the traffic volumes along all state highways as a part of its maintenance responsibilities using a metric called average annual daily traffic (AADT). This measurement is a calculation of the traffic level along a segment of roadway for any average day of the year. In 2010, INDOT figured that 100 vehicles and 10 commercial vehicles AADT along the route. Major intersections The entire route is in Lynn Township, Posey County. References == External links ==	length	{ "answer_start": [ 126 ], "text": [ "0.89" ] }
Frederik Stjernfelt (born July 6, 1957) is a Danish professor and writer. As a professor, he lectures in science studies, history of ideas, and semiotics, at Aalborg University's Copenhagen department. Career Stjernfelt has been working as a reviewer and writer at 'Weekendavisen' since 1994. Earlier in his career, he was employed as an editor at Gyldendal's cultural journal 'Kritik' between 1993 and 2012. Stjernfelt has been a member of 'Danish Academy' since 2001. Also, he is cofounder of the political network 'Fri debat', which functions to promote freedom of speech. Subsequently, he has published a number of academic as well as popular books and articles. Achievements Stjernfelt has received a number of recognitions and prizes for his work. This includes 'Lærebogsprisen' for his book 'Tal en tanke' in 2006, the Danish Association of Masters and PhDs' research award in 2010, and Blixprisen's 'This year's effort for freedom of speech' in 2017.Besides his awards, Stjernfelt received funding from the Carlsberg Foundation to write a book on the Danish historic time period of total freedom of the press between 1770 and 1773. Private life Frederik Stjernfelt is married to the Danish translator, Agnete Dorph Stjernfelt. He is the father of the Danish artists, Agnes Stjernfelt and Karoline Stjernfelt. == References ==	place of birth	{ "answer_start": [ 158 ], "text": [ "Aalborg" ] }
Frederik Stjernfelt (born July 6, 1957) is a Danish professor and writer. As a professor, he lectures in science studies, history of ideas, and semiotics, at Aalborg University's Copenhagen department. Career Stjernfelt has been working as a reviewer and writer at 'Weekendavisen' since 1994. Earlier in his career, he was employed as an editor at Gyldendal's cultural journal 'Kritik' between 1993 and 2012. Stjernfelt has been a member of 'Danish Academy' since 2001. Also, he is cofounder of the political network 'Fri debat', which functions to promote freedom of speech. Subsequently, he has published a number of academic as well as popular books and articles. Achievements Stjernfelt has received a number of recognitions and prizes for his work. This includes 'Lærebogsprisen' for his book 'Tal en tanke' in 2006, the Danish Association of Masters and PhDs' research award in 2010, and Blixprisen's 'This year's effort for freedom of speech' in 2017.Besides his awards, Stjernfelt received funding from the Carlsberg Foundation to write a book on the Danish historic time period of total freedom of the press between 1770 and 1773. Private life Frederik Stjernfelt is married to the Danish translator, Agnete Dorph Stjernfelt. He is the father of the Danish artists, Agnes Stjernfelt and Karoline Stjernfelt. == References ==	spouse	{ "answer_start": [ 1214 ], "text": [ "Agnete Dorph Stjernfelt" ] }
Frederik Stjernfelt (born July 6, 1957) is a Danish professor and writer. As a professor, he lectures in science studies, history of ideas, and semiotics, at Aalborg University's Copenhagen department. Career Stjernfelt has been working as a reviewer and writer at 'Weekendavisen' since 1994. Earlier in his career, he was employed as an editor at Gyldendal's cultural journal 'Kritik' between 1993 and 2012. Stjernfelt has been a member of 'Danish Academy' since 2001. Also, he is cofounder of the political network 'Fri debat', which functions to promote freedom of speech. Subsequently, he has published a number of academic as well as popular books and articles. Achievements Stjernfelt has received a number of recognitions and prizes for his work. This includes 'Lærebogsprisen' for his book 'Tal en tanke' in 2006, the Danish Association of Masters and PhDs' research award in 2010, and Blixprisen's 'This year's effort for freedom of speech' in 2017.Besides his awards, Stjernfelt received funding from the Carlsberg Foundation to write a book on the Danish historic time period of total freedom of the press between 1770 and 1773. Private life Frederik Stjernfelt is married to the Danish translator, Agnete Dorph Stjernfelt. He is the father of the Danish artists, Agnes Stjernfelt and Karoline Stjernfelt. == References ==	occupation	{ "answer_start": [ 52 ], "text": [ "professor" ] }
Frederik Stjernfelt (born July 6, 1957) is a Danish professor and writer. As a professor, he lectures in science studies, history of ideas, and semiotics, at Aalborg University's Copenhagen department. Career Stjernfelt has been working as a reviewer and writer at 'Weekendavisen' since 1994. Earlier in his career, he was employed as an editor at Gyldendal's cultural journal 'Kritik' between 1993 and 2012. Stjernfelt has been a member of 'Danish Academy' since 2001. Also, he is cofounder of the political network 'Fri debat', which functions to promote freedom of speech. Subsequently, he has published a number of academic as well as popular books and articles. Achievements Stjernfelt has received a number of recognitions and prizes for his work. This includes 'Lærebogsprisen' for his book 'Tal en tanke' in 2006, the Danish Association of Masters and PhDs' research award in 2010, and Blixprisen's 'This year's effort for freedom of speech' in 2017.Besides his awards, Stjernfelt received funding from the Carlsberg Foundation to write a book on the Danish historic time period of total freedom of the press between 1770 and 1773. Private life Frederik Stjernfelt is married to the Danish translator, Agnete Dorph Stjernfelt. He is the father of the Danish artists, Agnes Stjernfelt and Karoline Stjernfelt. == References ==	member of	{ "answer_start": [ 443 ], "text": [ "Danish Academy" ] }
Frederik Stjernfelt (born July 6, 1957) is a Danish professor and writer. As a professor, he lectures in science studies, history of ideas, and semiotics, at Aalborg University's Copenhagen department. Career Stjernfelt has been working as a reviewer and writer at 'Weekendavisen' since 1994. Earlier in his career, he was employed as an editor at Gyldendal's cultural journal 'Kritik' between 1993 and 2012. Stjernfelt has been a member of 'Danish Academy' since 2001. Also, he is cofounder of the political network 'Fri debat', which functions to promote freedom of speech. Subsequently, he has published a number of academic as well as popular books and articles. Achievements Stjernfelt has received a number of recognitions and prizes for his work. This includes 'Lærebogsprisen' for his book 'Tal en tanke' in 2006, the Danish Association of Masters and PhDs' research award in 2010, and Blixprisen's 'This year's effort for freedom of speech' in 2017.Besides his awards, Stjernfelt received funding from the Carlsberg Foundation to write a book on the Danish historic time period of total freedom of the press between 1770 and 1773. Private life Frederik Stjernfelt is married to the Danish translator, Agnete Dorph Stjernfelt. He is the father of the Danish artists, Agnes Stjernfelt and Karoline Stjernfelt. == References ==	family name	{ "answer_start": [ 9 ], "text": [ "Stjernfelt" ] }
Frederik Stjernfelt (born July 6, 1957) is a Danish professor and writer. As a professor, he lectures in science studies, history of ideas, and semiotics, at Aalborg University's Copenhagen department. Career Stjernfelt has been working as a reviewer and writer at 'Weekendavisen' since 1994. Earlier in his career, he was employed as an editor at Gyldendal's cultural journal 'Kritik' between 1993 and 2012. Stjernfelt has been a member of 'Danish Academy' since 2001. Also, he is cofounder of the political network 'Fri debat', which functions to promote freedom of speech. Subsequently, he has published a number of academic as well as popular books and articles. Achievements Stjernfelt has received a number of recognitions and prizes for his work. This includes 'Lærebogsprisen' for his book 'Tal en tanke' in 2006, the Danish Association of Masters and PhDs' research award in 2010, and Blixprisen's 'This year's effort for freedom of speech' in 2017.Besides his awards, Stjernfelt received funding from the Carlsberg Foundation to write a book on the Danish historic time period of total freedom of the press between 1770 and 1773. Private life Frederik Stjernfelt is married to the Danish translator, Agnete Dorph Stjernfelt. He is the father of the Danish artists, Agnes Stjernfelt and Karoline Stjernfelt. == References ==	given name	{ "answer_start": [ 0 ], "text": [ "Frederik" ] }
Frederik Stjernfelt (born July 6, 1957) is a Danish professor and writer. As a professor, he lectures in science studies, history of ideas, and semiotics, at Aalborg University's Copenhagen department. Career Stjernfelt has been working as a reviewer and writer at 'Weekendavisen' since 1994. Earlier in his career, he was employed as an editor at Gyldendal's cultural journal 'Kritik' between 1993 and 2012. Stjernfelt has been a member of 'Danish Academy' since 2001. Also, he is cofounder of the political network 'Fri debat', which functions to promote freedom of speech. Subsequently, he has published a number of academic as well as popular books and articles. Achievements Stjernfelt has received a number of recognitions and prizes for his work. This includes 'Lærebogsprisen' for his book 'Tal en tanke' in 2006, the Danish Association of Masters and PhDs' research award in 2010, and Blixprisen's 'This year's effort for freedom of speech' in 2017.Besides his awards, Stjernfelt received funding from the Carlsberg Foundation to write a book on the Danish historic time period of total freedom of the press between 1770 and 1773. Private life Frederik Stjernfelt is married to the Danish translator, Agnete Dorph Stjernfelt. He is the father of the Danish artists, Agnes Stjernfelt and Karoline Stjernfelt. == References ==	languages spoken, written or signed	{ "answer_start": [ 45 ], "text": [ "Danish" ] }
Zaamslagveer is a hamlet in the Dutch province of Zeeland. It is a part of the municipality of Terneuzen, and lies about 30 km southeast of Vlissingen. Zaamslagveer is not a statistical entity, and the postal authorities have placed in under Zaamslag. Place name signs are present. 134 people lived in Zaamslagveer in 1840. There are currently about 50 homes there. == References ==	located in the administrative territorial entity	{ "answer_start": [ 95 ], "text": [ "Terneuzen" ] }

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