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Aristotle wrote in his book Meteorology about an Antarctic region in c. 350 B.C. Marinus of Tyre reportedly used the name in his unpreserved world map from the 2nd century A.D. The Roman authors Hyginus and Apuleius (1–2 centuries A.D.) used for the [[South Pole]] the romanised Greek name ''polus antarcticus'', from which derived the Old French ''pole antartike'' (modern ''pôle antarctique'') attested in 1270, and from there the Middle English ''pol antartik'' in a 1391 technical treatise by Geoffrey Chaucer. | Aristotle wrote in his book Meteorology about an Antarctic region in c. 350 B.C. Marinus of Tyre reportedly used the name in his unpreserved world map from the 2nd century A.D. The Roman authors Hyginus and Apuleius (1–2 centuries A.D.) used for the [[South Pole]] the romanised Greek name ''polus antarcticus'', from which derived the Old French ''pole antartike'' (modern ''pôle antarctique'') attested in 1270, and from there the Middle English ''pol antartik'' in a 1391 technical treatise by Geoffrey Chaucer. | ||
Before acquiring its present geographical connotations, the term was used for other locations that could be defined as "opposite to the north". For example, the short-lived French colony established in Brazil in the 16th century was called "France Antarctique". | Before acquiring its present geographical connotations, the term was used for other locations that could be defined as "opposite to the north". For example, the short-lived French colony established in [[Brazilian Antarctica|Brazil]] in the 16th century was called "France Antarctique". | ||
The first formal use of the name "Antarctica" as a continental name in the 1890s is attributed to the Scottish cartographer John George Bartholomew. | The first formal use of the name "Antarctica" as a continental name in the 1890s is attributed to the Scottish cartographer John George Bartholomew. | ||
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European maps continued to show this hypothesized land until Captain James Cook's ships, HMS Resolution and Adventure, crossed the Antarctic Circle on 17 January 1773, in December 1773 and again in January 1774. Cook came within about 120 km (75 mi) of the Antarctic coast before retreating in the face of field ice in January 1773. The first confirmed sighting of Antarctica can be narrowed down to the crews of ships captained by three individuals. | ===Early exploration=== | ||
[[File:Admiral Bellingshausen.jpg|thumb|Fabian von Bellingshausen]] | |||
European maps continued to show this hypothesized land until Captain James Cook's ships, HMS Resolution and Adventure, crossed the [[Antarctic Circle]] on 17 January 1773, in December 1773 and again in January 1774. Cook came within about 120 km (75 mi) of the Antarctic coast before retreating in the face of field ice in January 1773. The first confirmed sighting of Antarctica can be narrowed down to the crews of ships captained by three individuals. | |||
According to various organisations, ships captained by three men sighted Antarctica or its ice shelf in 1820: [[Fabian Gottlieb von Bellingshausen]] (a captain in the Imperial Russian Navy), | According to various organisations, ships captained by three men sighted Antarctica or its ice shelf in 1820: [[Fabian Gottlieb von Bellingshausen]] (a captain in the Imperial Russian Navy), Edward Bransfield (a captain in the Royal Navy), and Nathaniel Palmer (a sealer out of Stonington, Connecticut). | ||
The First Russian Antarctic expedition led by Bellingshausen and Mikhail Lazarev on the 985-ton sloop-of-war ''Vostok'' and the 530-ton support vessel ''Mirny'' reached a point within 32 km (20 mi) from Queen Maud's Land and recorded the sight of an [[ice-shelf|ice shelf]] at 69°21′28″S 2°14′50″W, on 27 January, which became known as the "Fimbul ice shelf". This happened three days before Bransfield sighted land, and ten months before Palmer did so in November 1820. The first documented landing on Antarctica was by the American sealer John Davis, apparently at Hughes Bay, near Cape Charles, in West Antarctica on 7 February 1821, although some historians dispute this claim. | The First Russian Antarctic expedition led by Bellingshausen and Mikhail Lazarev on the 985-ton sloop-of-war ''Vostok'' and the 530-ton support vessel ''Mirny'' reached a point within 32 km (20 mi) from Queen Maud's Land and recorded the sight of an [[ice-shelf|ice shelf]] at 69°21′28″S 2°14′50″W, on 27 January, which became known as the "Fimbul ice shelf". This happened three days before Bransfield sighted land, and ten months before Palmer did so in November 1820. The first documented landing on Antarctica was by the American sealer John Davis, apparently at Hughes Bay, near Cape Charles, in West Antarctica on 7 February 1821, although some historians dispute this claim. | ||
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In December 1839, as part of the United States Exploring Expedition of 1838–42 conducted by the United States Navy (sometimes called the "Ex. Ex.", or "the Wilkes Expedition"), an expedition sailed from Sydney, Australia, into the [[Southern Ocean]] and reported the discovery "of an Antarctic continent west of the Balleny Islands" on 25 January 1840. That part of Antarctica was later named "Wilkes Land", a name it retains to this day. | In December 1839, as part of the United States Exploring Expedition of 1838–42 conducted by the United States Navy (sometimes called the "Ex. Ex.", or "the Wilkes Expedition"), an expedition sailed from Sydney, Australia, into the [[Southern Ocean]] and reported the discovery "of an Antarctic continent west of the Balleny Islands" on 25 January 1840. That part of Antarctica was later named "Wilkes Land", a name it retains to this day. | ||
Explorer [[James Clark Ross]] passed through what is now known as the Ross Sea and discovered Ross Island (both of which were named after him) in 1841. He sailed along a huge wall of ice that was later named the Ross Ice Shelf. Mount Erebus and Mount Terror are named after two ships from his expedition: HMS Erebus and Terror. Mercator Cooper landed in [[East Antarctica]] on 26 January 1853. | Explorer [[James Clark Ross]] passed through what is now known as the Ross Sea and discovered Ross Island (both of which were named after him) in 1841. He sailed along a huge wall of ice that was later named the Ross Ice Shelf. [[Mount Erebus]] and Mount Terror are named after two ships from his expedition: HMS ''Erebus'' and [[HMS Terror|HMS ''Terror'']]. Mercator Cooper landed in [[East Antarctica]] on 26 January 1853. | ||
During the Nimrod Expedition led by [[Ernest Shackleton]] in 1907, parties led by Edgeworth David became the first to climb Mount Erebus and to reach the [[South Magnetic Pole]]. [[Douglas Mawson]], who assumed the leadership of the Magnetic Pole party on their perilous return, went on to lead several expeditions until retiring in 1931. In addition, Shackleton himself and three other members of his expedition made several firsts in December 1908 – February 1909: they were the first humans to traverse the [[Ross Ice Shelf]], the first to traverse the [[Transantarctic Mountains]] (via the [[Beardmore Glacier]]), and the first to set foot on the | ===Modern day exploration=== | ||
[[File:Scott's party at the South Pole.jpg|thumb|left|British explorer Robert Scott at the South Pole]] | |||
During the Nimrod Expedition led by [[Ernest Shackleton]] in 1907, parties led by Edgeworth David became the first to climb Mount Erebus and to reach the [[South Magnetic Pole]]. [[Douglas Mawson]], who assumed the leadership of the Magnetic Pole party on their perilous return, went on to lead several expeditions until retiring in 1931. In addition, Shackleton himself and three other members of his expedition made several firsts in December 1908 – February 1909: they were the first humans to traverse the [[Ross Ice Shelf]], the first to traverse the [[Transantarctic Mountains]] (via the [[Beardmore Glacier]]), and the first to set foot on the South Polar Plateau. An expedition led by Norwegian polar explorer [[Roald Amundsen]] from the ship ''[[Fram]]'' became the first to reach the geographic [[South Pole]] on 14 December 1911, using a route from the [[Bay of Whales]] and up the Axel Heiberg Glacier. One month later, the doomed Scott Expedition reached the pole. | |||
[[Richard E. Byrd]] led several voyages to the Antarctic by plane in the 1930s and 1940s. He is credited with implementing mechanized land transport on the continent and conducting extensive geological and biological research. The first women to set foot on Antarctica did so in the 1930s with | [[Richard E. Byrd]] led several voyages to the Antarctic by plane in the 1930s and 1940s. He is credited with implementing mechanized land transport on the continent and conducting extensive geological and biological research. The first women to set foot on Antarctica did so in the 1930s with Caroline Mikkelsen landing on an island of Antarctica in 1935, and Ingrid Christensen stepping onto the mainland in 1937. | ||
It was not until 31 October 1956 that anyone set foot on the [[South Pole]] again; on that day a U.S. Navy group led by Rear Admiral George J. Dufek successfully landed an aircraft there. The first women to step onto the South Pole were Pam Young, Jean Pearson, Lois Jones, Eileen McSaveney, Kay Lindsay and Terry Tickhill in 1969. | It was not until 31 October 1956 that anyone set foot on the [[South Pole]] again; on that day a U.S. Navy group led by Rear [[Admiral George J. Dufek]] successfully landed an aircraft there. The first women to step onto the South Pole were Pam Young, Jean Pearson, Lois Jones, Eileen McSaveney, Kay Lindsay and Terry Tickhill in 1969. | ||
The first person to sail single-handed to Antarctica was the New Zealander David Henry Lewis, in 1972, in the 10-meter steel sloop ''Ice Bird''. | The first person to sail single-handed to Antarctica was the New Zealander David Henry Lewis, in 1972, in the 10-meter steel sloop ''Ice Bird''. | ||
==Geography== | ==Geography== | ||
There are a number of rivers and lakes in Antarctica, the longest river being the | [[File:Hull Glacier.jpg|thumb|400px|The Hull Glacier is typical of the glaciated landscape of Antarctica]] | ||
There are a number of rivers and lakes in Antarctica, the longest river being the Onyx. The largest lake, Vostok, is one of the largest sub-glacial lakes in the world. Antarctica covers more than 14 million km2 (5,400,000 sq mi), making it the fifth-largest continent, about 1.3 times as large as Europe. The coastline measures 17,968 km (11,165 mi) and is mostly characterized by ice formations, as the following table shows: | |||
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More than 170 million years ago, Antarctica was part of the supercontinent Gondwana. Over time, Gondwana gradually broke apart and Antarctica as we know it today was formed around 25 million years ago. Antarctica was not always cold, dry, and covered in ice sheets. At a number of points in its long history, it was farther north, experienced a tropical or temperate climate, was covered in forests, and inhabited by various ancient life forms. | More than 170 million years ago, Antarctica was part of the supercontinent Gondwana. Over time, Gondwana gradually broke apart and Antarctica as we know it today was formed around 25 million years ago. Antarctica was not always cold, dry, and covered in ice sheets. At a number of points in its long history, it was farther north, experienced a tropical or temperate climate, was covered in forests, and inhabited by various ancient life forms. | ||
The geological study of Antarctica has been greatly hindered by nearly all of the continent being permanently covered with a thick layer of [[ice]]. However, new techniques such as remote sensing, ground-penetrating radar and satellite imagery have begun to reveal the structures beneath the ice. | The geological study of Antarctica has been greatly hindered by nearly all of the continent being permanently covered with a thick layer of [[ice]]. However, new techniques such as remote sensing, ground-penetrating radar and satellite imagery have begun to reveal the structures beneath the ice. | ||
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==Human population== | ==Human population== | ||
[[File:Orientation to Fosdick Mountains.jpg|thumb|Scientists working in the Fosdick Mountains]] | |||
Several governments maintain permanent manned research stations on the continent. The number of people conducting and supporting scientific research and other work on the continent and its nearby islands varies from about 1,000 in winter to about 5,000 in the summer, giving it a population density between 70 and 350 inhabitants per million square kilometers (180 and 900 per million square miles) at these times. Many of the stations are staffed year-round, the winter-over personnel typically arriving from their home countries for a one-year assignment. An Orthodox church—Trinity Church, opened in 2004 at the Russian Bellingshausen Station—is manned year-round by one or two priests, who are similarly rotated every year. | Several governments maintain permanent manned research stations on the continent. The number of people conducting and supporting scientific research and other work on the continent and its nearby islands varies from about 1,000 in winter to about 5,000 in the summer, giving it a population density between 70 and 350 inhabitants per million square kilometers (180 and 900 per million square miles) at these times. Many of the stations are staffed year-round, the winter-over personnel typically arriving from their home countries for a one-year assignment. An Orthodox church—Trinity Church, opened in 2004 at the Russian Bellingshausen Station—is manned year-round by one or two priests, who are similarly rotated every year. | ||
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==Animals== | ==Animals== | ||
Few terrestrial vertebrates live in Antarctica, and those that do are limited to the sub-Antarctic islands. Invertebrate life includes microscopic mites like the ''Alaskozetes antarcticus'', lice, nematodes, tardigrades, rotifers, [[krill]] and springtails. The flightless midge ''Belgica antarctica'', up to 6 mm (1⁄4 in) in size, is the largest purely terrestrial animal in Antarctica. The [[snow petrel]] is one of only three birds that breed exclusively in Antarctica. | [[File:EmperorPenguinFeedingChick.jpg|thumb|Emperor penguin with chick]] | ||
Few terrestrial vertebrates live in Antarctica, and those that do are limited to the sub-Antarctic islands. Invertebrate life includes microscopic mites like the ''Alaskozetes antarcticus'', lice, nematodes, tardigrades, rotifers, [[krill]] and springtails. The flightless midge ''[[Antarctic midge|Belgica antarctica]]'', up to 6 mm (1⁄4 in) in size, is the largest purely terrestrial animal in Antarctica. The [[snow petrel]] is one of only three birds that breed exclusively in Antarctica. | |||
Some species of marine animals exist and rely, directly or indirectly, on the phytoplankton. Antarctic sea life includes penguins, [[blue whale]]s, [[orca]]s, [[colossal squid]]s and fur seals. The [[emperor penguin]] is the only penguin that breeds during the winter in Antarctica, while the [[Adélie penguin]] breeds farther south than any other penguin. The southern rockhopper penguin has distinctive feathers around the eyes, giving the appearance of elaborate eyelashes. [[King penguin]]s, [[chinstrap penguin]]s, and [[gentoo penguin]]s also breed in the Antarctic. | Some species of marine animals exist and rely, directly or indirectly, on the phytoplankton. Antarctic sea life includes penguins, [[blue whale]]s, [[orca]]s, [[colossal squid]]s and fur seals. The [[emperor penguin]] is the only penguin that breeds during the winter in Antarctica, while the [[Adélie penguin]] breeds farther south than any other penguin. The southern rockhopper penguin has distinctive feathers around the eyes, giving the appearance of elaborate eyelashes. [[King penguin]]s, [[chinstrap penguin]]s, and [[gentoo penguin]]s also breed in the Antarctic. | ||
The Antarctic fur seal was very heavily hunted in the 18th and 19th centuries for its pelt by sealers from the United States and the United Kingdom. The [[Weddell seal]], a "true seal", is named after Sir James Weddell, commander of British sealing expeditions in the Weddell Sea. [[Antarctic krill]], which congregate in large schools, is the keystone species of the ecosystem of the [[Southern Ocean]], and is an important food organism for whales, seals, [[leopard seal]]s, fur seals, squid, icefish, penguins, albatrosses and many other birds. | The Antarctic fur seal was very heavily hunted in the 18th and 19th centuries for its pelt by sealers from the United States and the United Kingdom. The [[Weddell seal]], a "true seal", is named after Sir James Weddell, commander of British sealing expeditions in the [[Weddell Sea]]. [[Antarctic krill]], which congregate in large schools, is the keystone species of the ecosystem of the [[Southern Ocean]], and is an important food organism for whales, seals, [[leopard seal]]s, fur seals, squid, icefish, penguins, albatrosses and many other birds. | ||
A census of sea life carried out during the International Polar Year and which involved some 500 researchers was released in 2010. The research is part of the global Census of Marine Life (CoML) and has disclosed some remarkable findings. More than 235 marine organisms live in both polar regions, having bridged the gap of 12,000 km (7,456 mi). Large animals such as some cetaceans and birds make the round trip annually. More surprising are small forms of life such as sea cucumbers, and free-swimming snails found in both polar oceans. Various factors may aid in their distribution – fairly uniform temperatures of the deep ocean at the poles and the equator which differ by no more than 5 °C, and the major current systems or marine conveyor belt which transport eggs and larval stages. | A census of sea life carried out during the International Polar Year and which involved some 500 researchers was released in 2010. The research is part of the global Census of Marine Life (CoML) and has disclosed some remarkable findings. More than 235 marine organisms live in both polar regions, having bridged the gap of 12,000 km (7,456 mi). Large animals such as some cetaceans and birds make the round trip annually. More surprising are small forms of life such as sea cucumbers, and free-swimming snails found in both polar oceans. Various factors may aid in their distribution – fairly uniform temperatures of the deep ocean at the poles and the equator which differ by no more than 5 °C, and the major current systems or marine conveyor belt which transport eggs and larval stages. | ||
==Fungi== | ==Fungi== | ||
About 1,150 species of fungi have been recorded from Antarctica, of which about 750 are non-lichen-forming and 400 are lichen-forming. Some of these species are cryptoendoliths as a result of evolution under extreme conditions, and have significantly contributed to shaping the impressive rock formations of the McMurdo Dry Valleys and surrounding mountain ridges. The apparently simple morphology, scarcely differentiated structures, metabolic systems and enzymes still active at very low temperatures, and reduced life cycles shown by such fungi make them particularly suited to harsh environments such as the McMurdo Dry Valleys. In particular, their thick-walled and strongly melanised cells make them resistant to UV light. Those features can also be observed in algae and cyanobacteria, suggesting that these are adaptations to the conditions prevailing in Antarctica. This has led to speculation that, if life ever occurred on Mars, it might have looked similar to Antarctic fungi such as Cryomyces antarcticus, and Cryomyces minteri. Some of these fungi are also apparently endemic to Antarctica. | About 1,150 species of fungi have been recorded from Antarctica, of which about 750 are non-[[lichen]]-forming and 400 are [[lichen]]-forming. Some of these species are cryptoendoliths as a result of evolution under extreme conditions, and have significantly contributed to shaping the impressive rock formations of the McMurdo Dry Valleys and surrounding mountain ridges. The apparently simple morphology, scarcely differentiated structures, metabolic systems and enzymes still active at very low temperatures, and reduced life cycles shown by such fungi make them particularly suited to harsh environments such as the McMurdo Dry Valleys. In particular, their thick-walled and strongly melanised cells make them resistant to UV light. Those features can also be observed in algae and cyanobacteria, suggesting that these are adaptations to the conditions prevailing in Antarctica. This has led to speculation that, if life ever occurred on Mars, it might have looked similar to Antarctic fungi such as Cryomyces antarcticus, and Cryomyces minteri. Some of these fungi are also apparently endemic to Antarctica. | ||
Endemic Antarctic fungi also include certain dung-inhabiting species which have had to evolve in response to the double challenge of extreme cold while growing on dung, and the need to survive passage through the gut of warm-blooded animals. | Endemic Antarctic fungi also include certain dung-inhabiting species which have had to evolve in response to the double challenge of extreme cold while growing on dung, and the need to survive passage through the gut of warm-blooded animals. | ||
==Plants== | ==Plants== | ||
About 298 million years ago Permian forests started to cover the continent, and tundra vegetation survived as late as 15 million years ago, but the climate of present-day Antarctica does not allow extensive vegetation to form. A combination of freezing temperatures, poor soil quality, lack of moisture, and lack of sunlight inhibit plant growth. As a result, the diversity of plant life is very low and limited in distribution. The flora of the continent largely consists of bryophytes. There are about 100 species of | About 298 million years ago Permian forests started to cover the continent, and tundra vegetation survived as late as 15 million years ago, but the climate of present-day Antarctica does not allow extensive vegetation to form. A combination of freezing temperatures, poor soil quality, lack of moisture, and lack of sunlight inhibit plant growth. As a result, the diversity of plant life is very low and limited in distribution. The flora of the continent largely consists of bryophytes. There are about 100 species of [[moss]]es and 25 species of liverworts, but only three species of flowering plants, all of which are found in the Antarctic Peninsula: ''Deschampsia antarctica'' (Antarctic hair grass), ''Colobanthus quitensis'' (Antarctic pearlwort) and the non-native ''Poa annua'' (annual bluegrass). Growth is restricted to a few weeks in the summer. | ||
===Other organisms=== | ===Other organisms=== | ||
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Some of Antarctica has been warming up; particularly strong warming has been noted on the Antarctic Peninsula. A study by Eric Steig published in 2009 noted for the first time that the continent-wide average surface temperature trend of Antarctica is slightly positive at >0.05 °C (0.09 °F) per decade from 1957 to 2006. This study also noted that West Antarctica has warmed by more than 0.1 °C (0.2 °F) per decade in the last 50 years, and this warming is strongest in winter and spring. This is partly offset by autumn cooling in [[East Antarctica]]. There is evidence from one study that Antarctica is warming as a result of human carbon dioxide emissions, but this remains ambiguous. The amount of surface warming in West Antarctica, while large, has not led to appreciable melting at the surface, and is not directly affecting the [[West Antarctic Ice Sheet]]'s contribution to sea level. Instead the recent increases in [[glacier]] outflow are believed to be due to an inflow of warm water from the deep ocean, just off the continental shelf. The net contribution to sea level from the [[Antarctic Peninsula]] is more likely to be a direct result of the much greater atmospheric warming there. | Some of Antarctica has been warming up; particularly strong warming has been noted on the Antarctic Peninsula. A study by Eric Steig published in 2009 noted for the first time that the continent-wide average surface temperature trend of Antarctica is slightly positive at >0.05 °C (0.09 °F) per decade from 1957 to 2006. This study also noted that West Antarctica has warmed by more than 0.1 °C (0.2 °F) per decade in the last 50 years, and this warming is strongest in winter and spring. This is partly offset by autumn cooling in [[East Antarctica]]. There is evidence from one study that Antarctica is warming as a result of human carbon dioxide emissions, but this remains ambiguous. The amount of surface warming in West Antarctica, while large, has not led to appreciable melting at the surface, and is not directly affecting the [[West Antarctic Ice Sheet]]'s contribution to sea level. Instead the recent increases in [[glacier]] outflow are believed to be due to an inflow of warm water from the deep ocean, just off the continental shelf. The net contribution to sea level from the [[Antarctic Peninsula]] is more likely to be a direct result of the much greater atmospheric warming there. | ||
In 2002 the Antarctic Peninsula's [[Larsen-B Ice Shelf]] collapsed. Between 28 February and 8 March 2008, about 570 km2 (220 sq mi) of ice from the | In 2002 the Antarctic Peninsula's [[Larsen-B Ice Shelf]] collapsed. Between 28 February and 8 March 2008, about 570 km2 (220 sq mi) of [[ice]] from the Wilkins Ice Shelf on the southwest part of the peninsula collapsed, putting the remaining 15,000 km2 (5,800 sq mi) of the ice shelf at risk. The ice was being held back by a "thread" of ice about 6 km (4 mi) wide, prior to its collapse on 5 April 2009. According to NASA, the most widespread Antarctic surface melting of the past 30 years occurred in 2005, when an area of ice comparable in size to California briefly melted and refroze; this may have resulted from temperatures rising to as high as 5 °C (41 °F). | ||
A study published in Nature Geoscience in 2013 (online in December 2012) identified central Westarctica as one of the fastest-warming regions on Earth. The researchers present a complete temperature record from [[Westarctica]]'s [[Byrd Station]] and assert that it "reveals a linear increase in annual temperature between 1958 and 2010 by 2.4±1.2 °C". | A study published in Nature Geoscience in 2013 (online in December 2012) identified central Westarctica as one of the fastest-warming regions on Earth. The researchers present a complete temperature record from [[Westarctica]]'s [[Byrd Station]] and assert that it "reveals a linear increase in annual temperature between 1958 and 2010 by 2.4±1.2 °C". | ||
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[[Category:Geography of Westarctica]] | [[Category:Geography of Westarctica]] | ||
[[Category:Antarctica]] | [[Category:Antarctica]] | ||
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