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{| border=1 align=right cellpadding=4 cellspacing=0 width=250 style="margin: 0 0 1em 1em; background: #f9f9f9; border: 1px #aaaaaa solid; border-collapse: collapse; font-size: 95%;"
|+<big><big>'''Antarctica'''</big></big>
| align=center colspan=2 style="background:#f9f9f9;" |
[[Image:LocationAntarctica.png|250px|Location of Antarctica.]]
|-
| '''[[Area]]''' || 14,000,000 km² (5,400,000 [[sq mi]]) 280,000 km² (108,000 sq mi) ice-free, 13,720,000 km² (5,297,000 sq mi) ice-covered
|-
| '''[[Population]]''' || ~1,000 (none permanent)
|-
| '''[[Government]]''' <br/>
|| governed by the [[Antarctic Treaty System]]<br/>
- current executive secretary [[Johannes Huber]]
|-
| '''[[Antarctic territorial claims|Territorial claims]]''' || {{ARG}} <br/> {{AUS}} <br/> {{CHL}} <br/> {{FRA}} <br/> {{NZL}} <br/> {{NOR}} <br/> {{GBR}}
|-
| '''Reserved the right to make claims''' || {{RUS}} <br/> {{USA}}
|-
| '''Internet [[Top-level domain|TLD]]''' || [[.aq]]
|-
| '''Calling Code''' || [[List of country calling codes#Locations with no country code|Listed Here]]
|}
[[Image:Adelie chicks in antarctica and Ms Explorer.jpg|thumb|300px|[[adelie|Adélie]] [[penguin]] chicks in [[Antarctica]], with [[MS Explorer|MS ''Explorer'']] and an [[iceberg]] in the background. The image was taken in January 1999. MS ''Explorer'' sunk on [[November 23]], [[2007]], after hitting an iceberg in Antarctica.]]
'''Antarctica''' is [[Earth]]'s southernmost [[continent]], overlying the [[South Pole]]. It is situated in the [[southern hemisphere]], almost entirely south of the [[Antarctic Circle]], and is surrounded by the [[Southern Ocean]]. At 14.4 million km² (5.4 million sq mi), it is the fifth-largest continent in area after [[Asia]], [[Africa]], [[North America]], and [[South America]]. Some 98% of Antarctica is covered by [[ice]], which averages at least 1.6 kilometres (1.0 [[statute mile|mi]]) in thickness.
On average, Antarctica is the coldest, driest and windiest continent, and has the highest average [[elevation]] of all the continents.<ref>{{cite web | title=National Geophysical Data Center | publisher=National Satellite, Data, and Information Service| url=http://www.ngdc.noaa.gov/mgg/image/2minrelief.html | accessmonthday=9 June |accessyear=2006}}</ref> Since there is little [[Precipitation (meteorology)|precipitation]], except at the coasts, the interior of the continent is technically the largest [[desert]] in the world. There are no permanent human residents and there is no evidence of any existing or pre-historic indigenous population. Only cold-adapted plants and animals survive there, including [[penguin]]s, [[fur seals]], [[moss]]es, [[lichen]], and many types of [[algae]].
The name ''Antarctica'' is a [[Romanization of Greek|romanized]] version of the [[Greek language|Greek]] compound word ''Αntarktiké'' (''Aνταρκτική''), meaning "Opposite of the [[Arctic]]".<ref>{{cite web|author=[[Henry Liddell|Liddell, Henry George]] and [[Robert Scott|Scott, Robert]]|work=[[A Greek-English Lexicon]] | publisher=Clarendon Press | title={{polytonic|ἀνταρκτικός}} | year=1940 | url=http://www.perseus.tufts.edu/cgi-bin/ptext?doc=Perseus:text:1999.04.0057:entry=%239514 | accessdate=12 February | accessyear=2006}}</ref> Although myths and speculation about a ''[[Terra Australis]]'' ("Southern Land") date back to antiquity, the first confirmed sighting of the continent is commonly accepted to have occurred in 1820 by the [[Russia]]n expedition of [[Mikhail Petrovich Lazarev|Mikhail Lazarev]] and [[Fabian Gottlieb von Bellingshausen]]. However, the continent remained largely neglected for the rest of the 19th century because of its hostile environment, lack of resources, and isolation.
The [[Antarctic Treaty System|Antarctic Treaty]] was signed in 1959 by twelve countries; to date, forty-five countries have signed the treaty. The treaty prohibits military activities and mineral mining, supports scientific research, and protects the continent's [[ecozone]]. Ongoing experiments are conducted by more than 4,000 scientists of many nationalities and with different research interests.<ref name="cia">{{cite web|url=https://www.cia.gov/library/publications/the-world-factbook/geos/ay.html#People|title=Antarctica - The World Factbook|publisher=United States Central Intelligence Agency|date=2007-03-08|accessdate=2007-03-14}}</ref>
==History==
{{main|History of Antarctica}} ''See also:'' ''[[List of Antarctic expeditions]]''
Belief in the existence of a ''Terra Australis''—a vast continent in the far south of the globe to "balance" the northern lands of [[Europe]], [[Asia]] and [[north Africa]]—had existed since the times of [[Ptolemy]] (1st century AD), who suggested the idea to preserve the [[symmetry]] of all known [[landmass]]es in the world. Depictions of a large southern landmass were common in maps such as the early 16th century [[Turkish]] [[Piri Reis map]]. Even in the late 17th century, after explorers had found that [[South America]] and [[Australia]] were not part of the fabled "Antarctica", geographers believed that the continent was much larger than its actual size.
[[Image:AntarcticaDomeCSnow.jpg|thumb|right|The snow surface at [[Dome C]] [[Concordia Station|Station]] is representative of the majority of the continent's surface.]]
[[Image:Antarctic-Iceberg.jpg|thumb|upright|An Iceberg dwarfs a ship in this 1920s English magazine illustration of a whaler in the Antarctic]]
European maps continued to show this hypothetical land until Captain [[James Cook]]'s ships, [[HMS Resolution (Cook)|HMS ''Resolution'']] and ''[[HMS Adventure (1771)|Adventure]]'', crossed the [[Antarctic Circle]] on [[January 17]], [[1773]], and once again in 1774.<ref>{{cite web | author=The Mariners' Museum | title=Age of Exploration: John Cook | url=http://www.mariner.org/educationalad/ageofex/cook.php | accessmonthday=12 February | accessyear=2006}}</ref> The first confirmed sighting of Antarctica can be narrowed down to the crews of ships captained by three individuals. According to various organizations (the [[National Science Foundation]],<ref>{{cite web | author=U.S. Antarctic Program External Panel of the [[National Science Foundation]] | title=Antarctica—Past and Present|url=http://www.nsf.gov/pubs/1997/antpanel/antpan05.pdf|accessmonthday=6 February |accessyear=2006}}</ref> [[NASA]],<ref>{{cite web|url=http://quest.arc.nasa.gov/antarctica/background/NSF/palmer.html|title=NATHANIEL BROWN PALMER, 1799-1877|publisher=NASA, U.S. Government|author=Guy G. Guthridge|accessdate=2006-02-06}}</ref> the [[University of California, San Diego]],<ref>{{cite web|url=http://arcane.ucsd.edu/pstat.html|title=Palmer Station|accessdate=2006-02-05}}</ref> and other sources<ref>{{cite web|url=http://www.south-pole.com/p0000052.htm|title=An Antarctic Time Line : 1519–1959|publisher=south-pole.com|accessdate=2006-02-12}}</ref><ref>{{cite web|url=http://ku-prism.org/polarscientist/timeline/antarcticexplorers1800.html|title=Antarctic Explorers Timeline: Early 1800s|accessdate=2006-02-12}}</ref>), ships captained by three men sighted Antarctica in 1820: [[Fabian Gottlieb von Bellingshausen]] (a captain in the [[Russian Imperial Navy]]), [[Edward Bransfield]] (a captain in the [[British Navy]]), and [[Nathaniel Palmer]] (an American [[Sealing|sealer]] out of [[Stonington, Connecticut]]). Von Bellingshausen saw Antarctica on [[January 27]], [[1820]], three days before Bransfield sighted land, and ten months before Palmer did so in November 1820. On that day the two-ship expedition led by Von Bellingshausen and [[Mikhail Petrovich Lazarev]] reached a point within 32 kilometers (20 mi) of the Antarctic mainland and saw ice fields there. The first documented landing on mainland Antarctica was by the American sealer [[John Davis (sealer)|John Davis]] in [[Western Antarctica]] on [[February 7]], [[1821]], although some historians dispute this claim.
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 [[Antarctic Ocean]], as it was then known, and reported the discovery "of an Antarctic continent west of the [[Balleny Islands]]". That part of Antarctica was later named "[[Wilkes Land]]", a name it maintains to this day.
In 1841, explorer [[James Clark Ross]] passed through what is now known as the [[Ross Sea]] and discovered [[Ross Island]] (both of which were named for him). He sailed along a huge wall of ice that was later named the [[Ross Ice Shelf]] (also named for him). [[Mount Erebus]] and [[Mount Terror (Antarctica)|Mount Terror]] are named after two ships from his expedition: [[HMS Erebus (1826)|HMS ''Erebus'']] and ''[[HMS Terror (1813)|Terror]]''.<ref>{{cite web|url=http://www.south-pole.com/p0000081.htm|title=South-Pole - Exploring Antarctica|accessdate=2006-02-12|publisher=south-pole.com}}</ref> [[Mercator Cooper]] landed in [[Eastern Antarctica]] on [[January 26]], [[1853]].<ref>{{cite web|url=http://www.antarctic-circle.org/firsts.htm|title=Antarctic Circle - Antarctic First|date=2005-02-09|accessdate=2006-02-12}}</ref>
[[Image:Shackleton expedition.jpg|left|thumb|[[Endurance (1912 ship)|''The Endurance'']] at night during [[Ernest Shackleton]]'s [[Imperial Trans-Antarctic Expedition]] in 1914.]]
During an [[Exploration|expedition]] led by [[Ernest Shackleton]] in 1907, parties led by [[T. W. 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.<ref>{{cite web|url=http://www.aad.gov.au/default.asp?casid=6660|title=''Tannatt William Edgeworth David''|publisher=Australian Government Antarctic Division|accessdate=2006-02-07}}</ref> 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 Mountain Range (via the [[Beardmore Glacier]]), and the first to set foot on the South Polar Plateau. On [[December 14]], [[1911]], an [[Amundsen's South Pole expedition|expedition]] led by Norwegian polar explorer [[Roald Amundsen]] from the ship ''[[Fram]]'' became the first to reach the geographic [[South Pole]], using a route from the [[Bay of Whales]] and up the [[Axel Heiberg Glacier]].<ref>{{cite web|url=http://www.south-pole.com/p0000101.htm|title=''Roald Amundsen''|publisher=south-pole.com|accessdate=2006-02-09}}</ref> One month later, the ill-fated [[Robert Falcon Scott|Scott Expedition]] reached the pole.
[[Richard Evelyn 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.<ref>{{cite web|url=http://www.70south.com/resources/antarctic-history/explorers/richardbyrd|title=Richard Byrd|publisher=70South.com|accessdate=2006-02-12}}</ref> However, it was not until [[October 31]], [[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.<ref>{{cite web|url=http://www.history.navy.mil/wars/datesoct.htm|title=Dates in American Naval History: October|publisher=U.S. Navy|accessdate=2006-02-12}}</ref>
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==Geography==
{{Main|Geography of Antarctica}}
[[Image:Antarctica 6400px from Blue Marble.jpg|thumb|right|A satellite composite image of Antarctica.]]
[[Image:Maritime-Antarctica.jpg|thumb|right|Maritime Antarctica.]]
[[Image:Europe antarctica size.png|thumb|Size comparison Europe-Antarctica.]]
Centered asymmetrically around the [[South Pole]] and largely south of the [[Antarctic Circle]], Antarctica is the southernmost continent and is surrounded by the [[Southern Ocean]]; alternatively, it may be considered to be surrounded by the southern [[Pacific Ocean|Pacific]], [[Atlantic Ocean|Atlantic]], and [[Indian Ocean]]s, or by the southern waters of the [[World Ocean]]. It covers more than 14 million km² (5.4 million sq mi), making it the fifth-largest continent, about 1.3 times larger than [[Europe]]. The coastline measures 17,968 kilometers (11,160 mi) and is mostly characterized by [[ice]] formations, as the following table shows:
{| class="wikitable"
|+ '''Coastal types around Antarctica (Drewry, 1983)'''
|-
! Type !! Frequency
|-
| [[Ice shelf]] (floating ice front)
|align=right| 44%
|-
| Ice walls (resting on ground)
|align=right| 38%
|-
| Ice stream/outlet glacier (ice front or ice wall)
|align=right| 13%
|-
| Rock
|align=right| 4%
|-
! Total
|align=right| 100%
|}
Antarctica is divided in two by the [[Transantarctic Mountains]] close to the neck between the [[Ross Sea]] and the [[Weddell Sea]]. The portion west of the Weddell Sea and east of the Ross Sea is called [[West Antarctica|Western Antarctica]] and the remainder [[Eastern Antarctica]], because they roughly correspond to the Western and Eastern Hemispheres relative to the [[Greenwich meridian]].
About 98% of Antarctica is covered by the [[Antarctic ice sheet]], a [[ice sheet|sheet]] of ice averaging at least 1.6 kilometers (1.0 mi) thick. The continent has about 90% of the world's ice (and thereby about 70% of the world's [[fresh water]]). If all of this ice were melted, sea levels would rise about 60 meters (200 ft).<ref name="howstuffworks">{{cite web|url=http://science.howstuffworks.com/question473.htm|title=How Stuff Works: polar ice caps|publisher=howstuffworks.com|accessdate=2006-02-12}}</ref> In most of the interior of the continent [[Precipitation (meteorology)|precipitation]] is very low, down to {{convert|20|mm|in|1|lk=on|sp=us}} per year; in a few "[[Blue ice (glacial)|blue ice]]" areas precipitation is lower than mass loss by [[Sublimation (chemistry)|sublimation]] and so the local mass balance is negative. In the [[McMurdo Dry Valleys|dry valleys]] the same effect occurs over a rock base, leading to a desiccated landscape.
Western Antarctica is covered by the [[West Antarctic Ice Sheet]]. The sheet has been of recent concern because of the real, if small, possibility of its collapse. If the sheet were to break down, [[Sea level change|ocean levels]] would rise by several meters in a relatively [[geological timescale|geologically short]] period of time, perhaps a matter of centuries. Several Antarctic [[ice stream]]s, which account for about 10% of the ice sheet, flow to one of the many [[Ice shelf#Antarctic ice shelves|Antarctic ice shelves]].
[[Image:Mt erebus.jpg|thumb|left|[[Mount Erebus]], an active volcano on [[Ross Island]].]]
[[Vinson Massif]], the highest peak in Antarctica at 4,892 meters (16,050 ft), is located in the [[Ellsworth Mountains]]. Although Antarctica is home to many volcanoes, only [[Mount Erebus]] is known to be active. Located on [[Ross Island]], Erebus is the southernmost active volcano. There is another famous volcano called [[Deception Island]], which is famous for its giant eruption in 1970. Minor eruptions are frequent and lava flow has been observed in recent years. Other dormant volcanoes may potentially be active.<ref>{{cite web|url=http://www.antarctica.ac.uk/About_Antarctica/Rock/Volcanoes.html|title=Volcanoes|publisher=British Antarctic Survey|accessdate=2006-02-13}}</ref> In 2004, an underwater volcano was found in the [[Antarctic Peninsula]] by American and Canadian researchers. Recent evidence shows this unnamed volcano may be active.<ref>{{cite web|url=http://www.nsf.gov/news/news_summ.jsp?cntn_id=100385|title=Scientists Discover Undersea Volcano Off Antarctica|publisher=United States National Science Foundation|accessdate=2006-02-13}}</ref>
Antarctica is home to more than 70 [[lake]]s that lie thousands of meters under the surface of the continental ice sheet. [[Lake Vostok]], discovered beneath [[Russia]]'s [[Vostok Station]] in 1996, is the largest of these [[subglacial lake]]s. It is believed that the lake has been sealed off for 500,000 to one million years. There is some evidence, in the form of [[ice core]]s drilled to about {{convert|400|m|ft|-2|sp=us}} above the water line, that Vostok's waters may contain [[microorganism|microbial life]]. The sealed, frozen surface of the lake shares similarities with [[Jupiter]]'s moon [[Europa (moon)|Europa]]. If life is discovered in Lake Vostok, this would strengthen the argument for the possibility of life on Europa.<ref>{{cite web|url=http://www.nsf.gov/od/lpa/news/02/fslakevostok.htm|title=Lake Vostok|publisher=United States National Science Foundation|accessdate=2006-02-13}}</ref><ref>{{cite web|url=http://astrobiology.arc.nasa.gov/stories/europa_vostok_0899.html|title=Lake Vostok may teach us about Europa|publisher=NASA|accessdate=2006-02-04}}</ref>
{{seealso|Extreme points of Antarctica|Antarctic territories|List of Antarctic and sub-Antarctic islands}}
==Geology==
{{Main|Geology of Antarctica}}
===Geological history and paleontology===
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.
====Paleozoic era (540–250 mya)====
[[Image:Survey-Route.jpg|thumb|right|Survey route]]
During the Cambrian period, Gondwana had a mild climate. West Antarctica was partially in the northern hemisphere, and during this period large amounts of [[sandstone]]s, [[limestone]]s and [[shale]]s were deposited. East Antarctica was at the equator, where sea floor [[invertebrate]]s and [[trilobite]]s flourished in the tropical seas. By the start of the Devonian period (416 [[Mya (unit)|mya]]), Gondwana was in more southern latitudes and the climate was cooler, though fossils of land plants are known from this time. [[Sand]] and [[silt]]s were laid down in what is now the [[Ellsworth Mountains|Ellsworth]], [[Horlick Mountains|Horlick]] and [[Pensacola Mountains]]. [[Glaciation]] began at the end of the Devonian period (360 mya), as Gondwana became centered around the [[South Pole]] and the climate cooled, though [[Antarctic flora|flora]] remained. During the Permian period, the plant life became dominated by [[fern]]-like plants such as ''[[Glossopteris]]'', which grew in swamps. Over time these swamps became deposits of coal in the [[Transantarctic Mountains]]. Towards the end of the Permian period, continued warming led to a dry, hot climate over much of Gondwana.<ref name="Stonehouse">{{cite book | editor = Stonehouse, B. (ed.) | title = Encyclopedia of Antarctica and the Southern Oceans | year = 2002 | month = June | publisher = John Wiley & Sons | id = ISBN 0-471-98665-8}}</ref>
====Mesozoic era (250–65 mya)====
[[Image:Bransfield-Strait.jpg|thumb|left|Bransfield Strait]]
As a result of continued warming, the polar ice caps melted and much of Gondwana became a desert. In East Antarctica, the [[seed fern]] became established, and large amounts of sandstone and shale were laid down at this time. The Antarctic Peninsula began to form during the Jurassic period (206–146 mya), and islands gradually rose out of the ocean. [[Ginkgo]] trees and [[cycad]]s were plentiful during this period, as were reptiles such as ''[[Lystrosaurus]]''. In West Antarctica, [[conifer]]ous [[forest]]s dominated through the entire Cretaceous period (146–65 mya), though [[Nothofagus|Southern beech]] began to take over at the end of this period. [[Ammonite]]s were common in the seas around Antarctica, and dinosaurs were also present, though only two Antarctic dinosaur species (''[[Cryolophosaurus]]'', from the [[Mount Kirkpatrick Formation|Hanson Formation]], and ''[[Antarctopelta]]'') have been described to date. It was during this period that Gondwana began to break up.
====Gondwana breakup (160–23 mya)====
The cooling of Antarctica occurred stepwise by the continental spread changing the oceanic currents from longitudinal equator-to-pole temperature-equalizing currents to latitudinal currents that preserved and accentuated latitude temperature differences.
[[Africa]] separated from Antarctica around 160 mya, followed by the [[Indian subcontinent]], in the early Cretaceous (about 125 mya). About 65 mya, Antarctica (then connected to [[Australia]]) still had a tropical to subtropical climate, complete with a [[marsupial]] fauna. About 40 mya [[Australia]]-[[New Guinea]] separated from Antarctica,
so that latitudinal current could isolate Antarctica from Australia, and so the first ice began to appear. Around 23 mya, the [[Drake Passage]] opened between Antarctica and [[South America]], which resulted in the [[Antarctic Circumpolar Current]]. The ice spread, replacing the forests that then covered the continent. Since about 15 mya, the continent has been mostly covered with ice,<ref name="Trewby">{{cite book | editor = Trewby, Mary (ed.) | title = Antarctica: An Encyclopedia from Abbott Ice Shelf to Zooplankton | year = 2002 | month = September | publisher = Firefly Books | id = ISBN 1-55297-590-8}}</ref> with the Antarctic ice cap reaching its present extension around 6 mya.
===Geology of present-day Antarctica===
[[Image:AntarcticaRockSurface.jpg|thumb|upright|Antarctica without its ice shield. This map does not consider that sea level would rise because of the melted ice, nor that the landmass would rise by several hundred meters over a few tens of thousands of years after the weight of the ice were no longer depressing the landmass.]]
[[Image:Port-Lockroy.jpg|thumb|[[Port Lockroy]] Museum.]]
The geological study of Antarctica has been greatly hindered by the fact that nearly all of the continent is 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.
Geologically, West Antarctica closely resembles the [[Andes]] mountain range of [[South America]].<ref name="Stonehouse" /> The [[Antarctic Peninsula]] was formed by uplift and [[metamorphism]] of sea bed sediments during the late Paleozoic and the early Mesozoic eras. This sediment uplift was accompanied by [[igneous]] intrusions and [[volcanism]]. The most common rocks in West Antarctica are [[andesite]] and [[rhyolite]] volcanics formed during the Jurassic period. There is also evidence of volcanic activity, even after the ice sheet had formed, in [[Marie Byrd Land]] and [[Alexander Island]]. The only anomalous area of West Antarctica is the [[Ellsworth Mountains]] region, where the [[stratigraphy]] is more similar to the eastern part of the continent.
East Antarctica is geologically very varied, dating from the [[Precambrian]] era, with some rocks formed more than 3 billion years ago. It is composed of a [[Metamorphic rock|metamorphic]] and [[igneous]] platform which is the basis of the [[Shield (geology)|continental shield]]. On top of this base are various modern rocks, such as [[sandstone]]s, [[limestone]]s, coal and [[shale]]s laid down during the Devonian and Jurassic periods to form the [[Transantarctic Mountains]]. In coastal areas such as [[Shackleton Range]] and [[Victoria Land]] some [[Geologic fault|faulting]] has occurred.
The main [[mineral]] resource known on the continent is [[coal]].<ref name="Trewby" /> It was first recorded near the [[Beardmore Glacier]] by [[Frank Wild]] on the [[Nimrod Expedition]], and now low-grade coal is known across many parts of the Transantarctic Mountains. The [[Prince Charles Mountains]] contain significant deposits of [[iron ore]]. The most valuable resources of Antarctica lie offshore, namely the [[oil field|oil]] and [[natural gas field]]s found in the [[Ross Sea]] in 1973. Exploitation of all mineral resources is banned until 2048 by the [[Protocol on Environmental Protection to the Antarctic Treaty]].
==Climate==
{{Main|Climate of Antarctica}}
[[Image:Fryxellsee Opt.jpg|thumb|left|The [[Blue ice (glacial)|blue ice]] covering [[Lake Fryxell]], in the [[Transantarctic Mountains]], comes from [[glacier|glacial]] meltwater from the [[Canada Glacier]] and other smaller glaciers.]]
[[Image:AntarcticaSummer.jpg|thumb|Near the coast, December looks fairly temperate.]]
Antarctica is the coldest place on [[Earth]]. At the 3-kilometer (2 mi)-high Vostok Station in Antarctica, scientists recorded the world's lowest temperature: {{nowrap|−89 °C}} {{nowrap|(−129 °F)}}.<ref>[http://weatherquesting.com/cold-places.htm Coldest spot on Earth]</ref> Antarctica is a frozen desert with little [[precipitation (meteorology)|precipitation]]; the South Pole itself receives less than 10 centimeters (4 in) per year, on average. Temperatures reach a minimum of between {{nowrap|−80 °C}} and {{nowrap|−90 °C}} {{nowrap|(−112 °F}} and {{nowrap|−130 °F)}} in the interior in winter and reach a maximum of between {{nowrap|5 °C}} and {{nowrap|15 °C}} {{nowrap|(41 °F}} and {{nowrap|59 °F)}} near the coast in summer. Sunburn is often a health issue as the snow surface reflects almost all of the ultraviolet light falling on it.<ref name="BAS-weather">{{cite web|url=http://www.antarctica.ac.uk/met/jds/weather/weather.htm|title=''Weather in the Antarctic''|publisher=British Antarctic Survey.|accessdate=2006-02-09}}</ref> Eastern Antarctica is colder than its western counterpart because of its higher elevation. [[Weather front]]s rarely penetrate far into the continent, leaving the center cold and dry. Despite the lack of precipitation over the central portion of the continent, [[ice]] there lasts for extended time periods. Heavy snowfalls are not uncommon on the coastal portion of the continent, where snowfalls of up to 1.22 meters (48 in) in 48 hours have been recorded. [[Image:Friesland-St-Boris.jpg|thumb|[[Cornice (climbing)|Snow cornices]] on a ridge top]] At the edge of the continent, strong [[katabatic wind]]s off the polar plateau often blow at storm force. In the interior, however, wind speeds are typically moderate. During summer, more [[solar radiation]] reaches the surface during clear days at the South Pole than at the [[equator]] because of the 24 hours of sunlight each day at the Pole.<ref name="cia" />
Antarctica is colder than the [[Arctic]] for two reasons. First, much of the continent is more than 3 kilometers (2 mi) above sea level, and temperature decreases with elevation. Second, the [[Arctic Ocean]] covers the north polar zone: the ocean's relative warmth is transferred through the icepack and prevents temperatures in the Arctic regions from reaching the extremes typical of the land surface of Antarctica.
Given the latitude, long periods of constant darkness or constant sunlight create climates unfamiliar to human beings in much of the rest of the world. The [[aurora australis]], commonly known as the southern lights, is a glow observed in the night sky near the South Pole. Another unique spectacle is [[diamond dust]], a ground-level cloud composed of tiny ice crystals. It generally forms under otherwise clear or nearly clear skies, so people sometimes also refer to it as clear-sky precipitation. A [[sun dog]], a frequent atmospheric [[optical phenomenon]], is a bright "spot" beside the true [[sun]].<ref name="BAS-weather" />
[[Image:iceberg09.jpg|thumb|500px|center|Tabletop [[iceberg]]s in Antarctica.]]
==Population==
{{seealso|Demographics of Antarctica}}
Antarctica has no permanent residents, but a number of governments maintain permanent [[research station]]s throughout the continent. The number of people conducting and supporting scientific research and other work on the continent and its nearby islands varies from about 4,000 in summer to about 1,000 in winter. Many of the stations are staffed year-round.
[[Image:Antarctic researchers.jpg|thumb|left|Two researchers studying [[plankton]] through [[microscope]]s.]]
The first semi-permanent inhabitants of regions near Antarctica (areas situated south of the [[Antarctic Convergence]]) were British and American sealers who used to spend a year or more on [[South Georgia Island|South Georgia]], from 1786 onward. During the [[whaling]] era, which lasted until 1966, the population of that island varied from over 1,000 in the summer (over 2,000 in some years) to some 200 in the winter. Most of the whalers were Norwegian, with an increasing proportion of Britons. The settlements included [[Grytviken]], [[Leith Harbour]], [[King Edward Point]], [[Stromness (South Georgia)|Stromness]], [[Husvik]], [[Prince Olav Harbour]], [[Ocean Harbour]] and [[Godthul]]. Managers and other senior officers of the whaling stations often lived together with their families. Among them was the founder of [[Grytviken]], Captain [[Carl Anton Larsen]], a prominent Norwegian whaler and explorer who, along with his family, adopted British citizenship in 1910.
[[Image:Fieldwork-Melnik.jpg|thumb|Field work.]]
The first child born in the southern polar region was Norwegian girl [[Solveig Gunbjörg Jacobsen]], born in Grytviken on [[8 October]] [[1913]], and her birth was registered by the resident British Magistrate of South Georgia. She was a daughter of Fridthjof Jacobsen, the assistant manager of the whaling station, and of Klara Olette Jacobsen. Jacobsen arrived on the island in 1904 to become the manager of [[Grytviken]], serving from 1914 to 1921; two of his children were born on the island.<ref>R.K. Headland, The Island of South Georgia, Cambridge University Press, 1984.</ref>
[[Emilio Marcos Palma]] was the first person born on the Antarctic mainland, at [[Esperanza Base|Base Esperanza]] in 1978; his parents were sent there along with seven other families by the [[Argentina|Argentinean]] government to determine if family life was suitable on the continent. In 1984, Juan Pablo Camacho was born at the [[Eduardo Frei Montalva Station]], becoming the first Chilean born in Antarctica. Several bases are now home to families with children attending schools at the station.<ref>{{cite web|url=http://antarcticsun.usap.gov/oldissues2002-2003/answer.html|title=Questions and answers|publisher=''The Antarctic Sun''|accessdate=2006-02-09}}</ref>
See the OMNI article: [http://english.ohmynews.com/ArticleView/article_view.asp?no=380296&rel_no=1 Living in Antarctica]
==Flora and fauna==
{{seealso|Antarctic ecozone}}
===Flora===
[[Image:Lichen squamulose.jpg|thumb|More than 200 species of [[lichen]]s are known in Antarctica.]]
The climate of Antarctica does not allow extensive vegetation. A combination of freezing temperatures, poor [[soil]] quality, lack of moisture, and lack of sunlight inhibit the flourishing of plants. As a result, plant life is limited to mostly [[moss]]es and [[Marchantiophyta|liverwort]]s. The [[autotroph]]ic community is made up of mostly [[protist]]s. The [[flora]] of the continent largely consists of [[lichen]]s, [[bryophyte]]s, [[algae]], and [[fungi]]. Growth generally occurs in the summer, and only for a few weeks at most.
There are more than 200 species of lichens and about 50 species of bryophytes, such as mosses. Seven hundred species of algae exist, most of which are [[phytoplankton]]. Multicolored [[snow algae]] and [[diatom]]s are especially abundant in the coastal regions during the summer. There are two species of flowering plants found in the Antarctic Peninsula: ''[[Deschampsia antarctica]]'' (Antarctic hair grass) and ''[[Colobanthus quitensis]]'' (Antarctic pearlwort).<ref>{{cite web|url=http://www.aad.gov.au/default.asp?casid=5551|title=Antarctic Wildlife|publisher=Australian Government Antarctic Division|accessdate=2006-02-05}}</ref>
===Fauna (Animals)===
Land [[fauna (animals)|fauna]] is nearly completely [[invertebrate]]. Invertebrate life includes [[microscopic]] [[mite]]s, [[lice]], [[Roundworm|nematode]]s, [[tardigrade]]s, [[rotifer]]s, [[krill]] and [[springtail]]s. The flightless [[midge (insect)|midge]] ''[[Belgica antarctica]]'', just {{convert|12|mm|in|1|sp=us}} in size, is the smallest land animal in Antarctica. The [[Snow Petrel]] is one of only three birds that breed exclusively in Antarctica. They have been seen at the [[South Pole]].
Due to the extreme cold, the body fluids of tiny mites and midges in Antarctica contain glycerol, an antifreeze liquid that protects them from solidifying when temperatures plummet to as low as {{nowrap|−34 °C}} {{nowrap|(−30 °F)}}.<ref>[http://weatherquesting.com/cold-places.htm Coldest spot on Earth]</ref>
[[Image:Emperor penguin.jpg|thumb|upright|[[Emperor Penguin]]s in [[Ross Sea]], Antarctica.]]
A variety of marine animals exist and rely, directly or indirectly, on the phytoplankton. Antarctic sea life includes [[penguin]]s, [[blue whales]], [[orca]]s and [[fur seal]]s. The [[Emperor penguin]] is the only penguin that breeds during the winter in Antarctica, while the [[Adelie Penguin|Adélie Penguin]] breeds farther south than any other penguin. The [[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 [[James Weddell|Sir James Weddell]], commander of [[United Kingdom|British]] sealing expeditions in the [[Weddell Sea]]. [[Antarctic krill]], which congregates in large [[swarm|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, [[albatross]]es and many other birds.<ref>{{cite web|url=http://www.knet.co.za/antarctica/fauna_and_flora.htm|title=Creatures of Antarctica|accessdate=2006-02-06}}</ref>
The passing of the [[Antarctic Conservation Act]] in the U.S. brought several restrictions to U.S. activity on the continent. The introduction of alien plants or animals can bring a criminal penalty, as can the extraction of any indigenous species. The [[overfishing]] of krill, which plays a large role in the Antarctic ecosystem, led officials to enact regulations on [[fishing]]. The Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR), a treaty that came into force in 1980, requires that regulations managing all Southern Ocean fisheries consider potential effects on the entire Antarctic ecosystem.<ref name="cia" /> Despite these new acts, unregulated and illegal fishing, particularly of [[Patagonian toothfish]] (marketed as Chilean Sea Bass in the U.S.), remains a serious problem. The illegal fishing of toothfish has been increasing, with estimates of 32,000 [[Metric ton|tonnes]] (35,300 short tons) in 2000.<ref>{{cite web|url=http://news.bbc.co.uk/2/hi/science/nature/1492380.stm|title=Toothfish at risk from illegal catches|publisher=BBC News|accessdate=2006-02-11}}</ref><ref>{{cite web|url=http://www.aad.gov.au/default.asp?casid=1539|title=Toothfish|publisher=Australian Government Antarctic Division|accessdate=2006-02-11}}</ref>
==Politics==
[[Image:Logistic-Support.jpg|thumb|left|Resupply by the Uruguayan Navy vessel ''Vanguardia''.]]
Antarctica has no government and belongs to no country. Various countries claim areas of it, although as a rule, no other countries recognize such claims. The area between 90° W and 150° W is the only part of Antarctica, indeed the only solid land on Earth, not claimed by any country.<ref name="cia" />
Since 1959, claims on Antarctica have been suspended and the continent is considered politically neutral. Its status is regulated by the 1959 [[Antarctic Treaty]] and other related agreements, collectively called the [[Antarctic Treaty System]]. For the purposes of the Treaty System, Antarctica is defined as all land and [[ice shelf|ice shelves]] south of 60° S. The treaty was signed by twelve countries, including the [[Soviet Union]] (and later [[Russia]]), the [[United Kingdom]], [[Argentina]] and the [[United States]]. It set aside Antarctica as a scientific preserve, established freedom of scientific investigation, environmental protection, and banned military activity on that continent. This was the first [[arms control]] agreement established during the [[Cold War]].
The Antarctic Treaty prohibits any [[Military activity in the Antarctic|military activity in Antarctica]], such as the establishment of military bases and fortifications, the carrying out of military manoeuvers, or the testing of any type of weapon. Military personnel or equipment are permitted only for scientific research or for other peaceful purposes.<ref>{{cite web|url=http://www.scar.org/treaty/|title=''Antarctic Treaty''|publisher=Scientific Committee on Antarctic Research|accessdate=2006-02-09}}</ref> The only documented land military manoeuvre was [[Operación 90|Operation NINETY]], undertaken by the [[Military of Argentina|Argentine military]].<ref>{{cite web|url=http://www.dna.gov.ar/INGLES/DIVULGAC/ARGANT.HTM|title=Argentina in Antarctica|publisher=Antarctica Institute of Argentina|accessdate=2006-02-09}}</ref>
The [[United States military]] issues the [[Antarctica Service Medal]] to military members or civilians who perform research duty in Antarctica. The medal includes a "wintered over" bar issued to those who remain on the continent for two complete six-month seasons.<ref>{{cite web|url=http://www.history.navy.mil/medals/antarc.htm|title=Antarctic Service Medal|publisher=U.S. Navy|accessdate=2006-02-09}}</ref>
===Antarctic territories===
[[Image:antarctica.jpg|thumb||Territorial claims of Antarctica.]]
{{main|Antarctic territorial claims}}
{| class="wikitable sortable"
!Date
!Country
!Territory
!Claim limits
|-
| 1908
| {{flagcountry|United Kingdom}}
| [[British Antarctic Territory]]
| {{coor d Antarctic|20|W}} to {{coor d Antarctic|80|W}}
|-
| 1923
| {{flagcountry|New Zealand}}
| [[Ross Dependency]]
| {{coor d Antarctic|150|W}} to {{coor d Antarctic|160|E}}
|-
| 1924
| {{flagcountry|France}}
| [[Adélie Land]]
| {{coor dm Antarctic|142|2|E}} to {{coor dm Antarctic|136|11|E}}
|-
| 1929
| {{flagcountry|Norway}}
| [[Peter I Island]]
| {{coor dm|68|50|S|90|35|W|}}
|-
| 1933
| {{flagcountry|Australia}}
| [[Australian Antarctic Territory]]
| {{coor d Antarctic|160|E}} to {{coor dm Antarctic|142|2|E}} and</br> {{coor dm Antarctic|136|11|E}} to {{coor dm Antarctic|44|38|E}}
|-
| 1939
| {{flagcountry|Norway}}
| [[Queen Maud Land]]
| {{coor dm Antarctic|44|38|E}} to {{coor d Antarctic|20|W}}
|-
| 1940
| {{flagcountry|Chile}}
| [[Antártica Chilena Province|Antarctic Chilean Territory]]
| {{coor d Antarctic|53|W}} to {{coor d Antarctic|90|W}}
|-
| 1943
| {{flagcountry|Argentina}}
| [[Argentine Antarctica]]
| {{coor d Antarctic|25|W}} to {{coor d Antarctic|74|W}}
|-
|
| None
| Unclaimed territory
| {{coor d Antarctic|90|W}} to {{coor d Antarctic|150|W}}</br>(except the [[Peter I Island]])
|}
The Argentine, British and Chilean claims all overlap. [[Australia]] has the greatest claim of Antarctic territory.
[[Germany]] also maintained a claim to Antarctica, known as [[New Swabia]], between 1939 and 1945. It was situated from {{coor d Antarctic|20|E}} to {{coor d Antarctic|10|W}}, overlapping Norway's claim. The claim was abandoned after the fall of Nazi Germany in 1945.
==Economy==
{{main|Economy of Antarctica}}
[[Image:Antarctic cod.jpg|thumb|left|The illegal capture and sale of the [[Patagonian toothfish]] has led to several arrests. Pictured here is the [[Antarctic toothfish]], a sister species.]]
Although [[coal]], [[hydrocarbon]]s, [[iron ore]], [[platinum]], [[copper]], [[chromium]], [[nickel]], [[gold]] and other minerals have been found, they have not been in large enough quantities to exploit. The 1991 [[Protocol on Environmental Protection to the Antarctic Treaty]] also restricts a struggle for resources. In 1998, a compromise agreement was reached to place an indefinite ban on mining, to be reviewed in 2048, further limiting economic development and exploitation. The primary agricultural activity is the capture and offshore trading of fish. Antarctic fisheries in 2000–01 reported landing 112,934 tonnes.<ref>{{cite web|url=http://www.biosbcc.net/ocean/AAimportance.htm|title=Importance of Antarctica|publisher=Santa Barbara City College Biological Sciences|accessdate=2006-02-05}}</ref>
[[Image:Antarctic-Postal-Services.jpg|thumb|Antarctic postal services.]]
Small-scale "expedition [[tourism]]" has existed since 1957 and is currently subject to Antarctic Treaty and Environmental Protocol provisions, but in effect self-regulated by the [[International Association of Antarctica Tour Operators]] (IAATO). Not all vessels associated with Antarctic tourism are members of IAATO, but IAATO members account for 95% of the tourist activity. Travel is largely by small or medium [[ship]], focusing on specific scenic locations with accessible concentrations of iconic wildlife. A total of 37,506 tourists visited during the 2006–07 [[Southern Hemisphere|Austral summer]] with nearly all of them coming from commercial ships. The number is predicted to increase to over 80,000 by 2010.<ref>{{cite web|url=http://30atcm.ats.aq/30atcm/Documents/Docs/fr/Atcm30_fr001_e.doc|title=Final Report, 30th Antarctic Treaty Consultative Meeting|publisher=Antarctic Treaty Secretariat|accessdate=2007-08-02}}</ref><ref>{{cite web|url=http://www.knet.co.za/antarctica/political.htm|title=Politics of Antarctica|accessdate=2006-02-05}}</ref> There has been some recent concern over the potential adverse environmental and ecosystem effects caused by the influx of visitors. A call for stricter regulations for ships and a tourism quota have been made by some environmentalists and scientists.<ref>{{cite web|url=http://www.telegraph.co.uk/travel/main.jhtml?xml=/travel/2006/02/11/etnewsant.xml&sSheet=/travel/2006/02/11/ixtrvhome.html|title=''Tourism threatens Antarctic''|publisher=''Telegraph UK''|accessdate=2006-02-05}}</ref> The primary response by Antarctic Treaty Parties has been to develop, through their Committee for Environmental Protection and in partnership with IAATO, "site use guidelines" setting landing limits and closed or restricted zones on the more frequently visited sites. Antarctic sight seeing flights (which did not land) operated out of Australia and New Zealand until the fatal crash of [[Air New Zealand Flight 901]] in 1979 on [[Mount Erebus]], which killed all 257 aboard. [[Qantas]] resumed commercial overflights to Antarctica from Australia in the mid-1990s.
==Transport==
{{main|Transport in Antarctica}}
Transport on the continent has transformed from explorers crossing the isolated remote area of Antarctica on foot to a more open area due to human technologies enabling more convenient and faster transport by land and predominantly air and water.
==Research==
[[Image:Amundsen-Scott marsstation ray h edit.jpg|thumb|A [[full moon]] and 25-second exposure allowed sufficient light for this photo to be taken at [[Amundsen-Scott South Pole Station]] during the long Antarctic night. The new station can be seen at far left, the [[power plant]] in the center and the old mechanic's garage in the lower right. The green light in the background is the [[Aurora Australis]].]]
{{seealso|List of research stations in Antarctica}}
Each year, scientists from 27 different nations conduct [[experiment]]s not reproducible in any other place in the world. In the summer more than 4,000 scientists operate [[research station]]s; this number decreases to nearly 1,000 in the winter.<ref name="cia" /> [[McMurdo Station]] is capable of housing more than 1,000 scientists, visitors, and tourists.
Researchers include [[Biology|biologists]], [[Geology|geologists]], [[Oceanography|oceanographers]], [[Physics|physicists]], [[Astronomy|astronomers]], [[Glaciology|glaciologists]], and [[Meterology|meteorologists]]. Geologists tend to study [[plate tectonics]], meteorites from [[outer space]], and resources from the breakup of the supercontinent [[Gondwanaland]]. Glaciologists in Antarctica are concerned with the study of the history and dynamics of floating [[ice]], [[snow|seasonal snow]], [[glacier]]s, and [[ice sheet]]s. Biologists, in addition to examining the wildlife, are interested in how harsh temperatures and the presence of people affect adaptation and survival strategies in a wide variety of organisms. Medical physicians have made discoveries concerning the spreading of viruses and the body's response to extreme seasonal temperatures. Astrophysicists at [[Amundsen-Scott South Pole Station]] study the celestial dome and [[cosmic microwave background radiation]]. Many astronomical observations are better made from the interior of Antarctica than from most surface locations because of the high elevation, which results in a thin atmosphere, and low temperature, which minimizes the amount of water vapour in the atmosphere, thus allowing for a view of space clearer than anywhere else on Earth. Antarctic ice serves as both the shield and the detection medium for the largest [[IceCube|neutrino telescope]] in the world, built 2 kilometers below Amundsen-Scott station.<ref>{{cite web|url=http://www.antarcticconnection.com/antarctic/science/index.shtml|title=Science in Antarctica|publisher=''Antarctic Connection''|accessdate=2006-02-04}}</ref>
Since the 1970s, an important focus of study has been the [[ozone layer]] in the [[atmosphere]] above Antarctica. In 1985, three British Scientists working on data they had gathered at [[Halley Station]] on the [[Brunt Ice Shelf]] discovered the existence of a hole in this layer. In 1998, [[NASA]] satellite data showed that the Antarctic [[ozone hole]] was the largest on record, covering 27 million km² (10 million sq mi). It was eventually determined that the destruction of the ozone was caused by [[Haloalkane#Chlorofluoro compounds .28CFC.2C HCFC.2C HFC.29|chlorofluorocarbons]] emitted by human products. With the ban of CFCs in the [[Montreal Protocol]] of 1989, it is believed that the ozone hole will close up over the next fifty years.
===Princess Elisabeth Polar Science Station===
On [[September 6]], [[2007]], [[Belgian]]-based International Polar Foundation unveiled [[octagonal]] [[spaceship]]-like Princess Elisabeth station, the world's first zero-emissions polar science station in Antarctica to [[research]] on [[climate change]]. Costing $16.3 million, the [[prefabricated]] station, which is part of [[International Polar Year]] will shipped to the [[South Pole]] from Belgium (to monitor the [[health]] of the [[polar]] regions, using [[icebreaker]]s, [[satellite]]s, [[station]]s and [[submarine]]s). Belgian polar [[explorer]] Alain Hubert has stated, "This base will be the first of its kind to produce zero emissions, making it a unique model of how energy should be used in the Antarctic." Johan Berte is the leader of the station design team and manager of the project (which will conduct research in [[climatology]], [[glaciology]] and [[microbiology]]), and the project unified [[scientist]]s from 63 nations in 228 studies.<ref>[http://news.yahoo.com/s/ap/20070905/ap_on_sc/belgium_polar_station;_ylt=AiISabb6uTrQkDc3pmDkTVqs0NUE Yahoo.com, Group unveils polar science station]</ref>
===Meteorites===
[[Image:ALH84001.jpg|thumb|Antarctic meteorite, named [[ALH84001]], from [[Mars]].]]
[[Meteorite]]s from Antarctica are an important area of study of material formed early in the [[solar system]]; most are thought to come from [[asteroid]]s, but some may have originated on larger [[planet]]s. The first meteorites were found in 1912. In 1969, a Japanese expedition discovered nine meteorites. Most of these meteorites have fallen onto the [[ice sheet]] in the last million years. Motion of the ice sheet tends to concentrate the meteorites at blocking locations such as mountain ranges, with wind erosion bringing them to the surface after centuries beneath accumulated snowfall. Compared with meteorites collected in more temperate regions on Earth, the Antarctic meteorites are well-preserved.<ref name="meteorite">{{cite web|url=http://www-curator.jsc.nasa.gov/antmet/index.cfm|title=Meteorites from Antarctica |publisher=NASA| accessdate=2006-02-09}}</ref>
This large collection of meteorites allows a better understanding of the abundance of meteorite types in the solar system and how meteorites relate to asteroids and comets. New types of meteorites and rare meteorites have been found. Among these are pieces blasted off the Moon, and probably Mars, by impacts. These specimens, particularly [[ALH84001]] discovered by [[ANSMET]], are at the center of the controversy about possible evidence of microbial life on Mars. Because meteorites in space absorb and record cosmic radiation, the time elapsed since the meteorite hit the Earth can be determined from laboratory studies. The elapsed time since fall, or terrestrial residence age, of a meteorite represents more information that might be useful in environmental studies of Antarctic ice sheets.<ref name="meteorite" />
In 2006, a team of researchers from [[Ohio State University]] used gravity measurements by NASA's [[Gravity Recovery and Climate Experiment|GRACE]] satellites to discover the {{convert|300|mi|km|-1|sing=on}}-wide [[Wilkes Land crater]], which probably formed about 250 million years ago.<ref name="crater">{{cite web| url=http://researchnews.osu.edu/archive/erthboom.htm| title=Big Bang in Antarctica—Killer Crater Found Under Ice| publisher=Research News| first=Pam Frost| last=Gorder| year=June 1, 2006}}</ref>
==Effects of global warming==
[[Image:160658main2 OZONE large 350.png|200px|right]]
Most of the continent's icy mass has so far proven largely impervious to [[climate change]], being situated on solid rock; its deep interior is actually growing in volume. <ref>The Economist, 3 November 2007, p. 78 </ref> However, Antarctica's periphery has been noticeably affected by [[global warming]], particularly on the [[Antarctic Peninsula]] and in [[Pine Island Bay]] which together are contributing to a rise in sea levels.<ref>The Economist, 3 November 2007, p. 78 </ref> In 2003 the [[Larsen Ice Shelf#Larsen-B| Larsen-B]] ice shelf collapsed owing to global warming.<ref name=BAS_2007_Larsen_global_warming>{{cite web | author = British antarctic survey | title = First direct evidence that human activity is linked to Antarctic Ice Shelf Collapse | url = http://www.antarctica.ac.uk/press/press_releases/press_release.php?id=82 }}</ref> According to [[NASA]], the most significant Antarctic melting in the past 30 years occurred in 2005, when a mass of ice comparable in size to [[California]] briefly melted and refroze; this may have resulted from temperatures rising to as high as {{nowrap|5 °C}} {{nowrap|(41 °F)}}.<ref name=cnn_2005_melt>{{cite web | author = Reuters | title = Big area of Antarctica melted in 2005 | publisher = CNN | date = 2007-05-16 | url = http://www.cnn.com/2007/TECH/science/05/16/antarctica.melting.reut/index.html | accessdate = 2007-06-11
}}</ref>
Also, although having no obvious effect on the continent's environment, there is a large [[ozone hole]] over Antarctica which was detected by scientists in 1973 and continues to grow to this day. The main cause is the [[Atmospheric emissions|emission]] of [[chlorofluorocarbons]] or CFCs into the [[atmosphere]], which decompose the [[ozone]] into other gasses. For more on the ozone hole, see [[Ozone depletion]].
==See also==
{{MultiCol}}
'''Geographic regions'''
*[[Antarctica ecozone]]
*[[Antarctic Peninsula]]
*[[Eastern Antarctica]]
*[[List of Antarctic and sub-Antarctic islands]]
*[[Extreme points of the Antarctic]]
*[[McMurdo Sound]]
*[[Ross Sea]]
*[[Weddell Sea]]
'''Geography'''
*[[List of Bulgarian toponyms in Antarctica]]
*[[List of deserts by area]]
*[[List of places with fewer than ten residents]] (Note: refers to permanent residents)
*[[List of research stations in Antarctica]]
*[[Ancient world maps]]
*[[World map]]
{{ColBreak}}
'''Geopolitics'''
*[[Argentine Antarctic Geopolitics]]
*[[Antarctic Treaty Secretariat]]
*[[Brazil Antarctic Geopolitics]]
*[[Chile Antarctic Geopolitics]]
*[[Flags of Antarctica]]
'''Other'''
* [[Antarctica Marathon]]
* [[Antarctic Stamps]]
* [[Soviet Antarctic Expedition]]
* [[Communications in Antarctica]]
* ''[[Life in the Freezer]]'', a [[BBC]] natural history [[television]] series on life on and around Antarctica
* The ''[[Icebird (ship)|Icebird]]'', an [[Australia]]n supply vessel.
* ''[[March of the Penguins]]'', an [[Academy Award]] winning [[documentary film]] depicting the annual journey [[Emperor Penguins]] make to their ancestral breeding grounds.
*[[Trinity Church, Antarctica]]
{{EndMultiCol}}
==References==
<!--This article uses the Cite.php citation mechanism. If you would like more information on how to add references to this article, please see http://meta.wikimedia.org/wiki/Cite/Cite.php -->
{{reflist|2}}
==External links==
{{wikisource|CIA World Fact Book, 2004/Antarctica}}
{{sisterlinks|Antarctica}}
*[http://www.ats.aq/ Antarctic Treaty Secretariat], ''de facto'' government
*{{dmoz|Regional/Polar_Regions/Antarctic/|Antarctic region}}
* [http://www.loc.gov/rr/international/frd/antarctica/antarctica.html Portals on the World - Antarctica] from the [[Library of Congress]]
*{{CIA World Factbook link|ay|Antarctica}}
* [http://lima.nasa.gov/ NASA's LIMA] (Landsat Image Mosaic of Antarctica) ([http://lima.usgs.gov/ USGS mirror]) ([http://www.gelib.com/maps/Offsite/LIMA_nl.kml LIMA WMS Service in Google Earth])
* [http://wikitravel.org/en/Antarctica Antarctica travel guide] from [http://wikitravel.org WikiTravel]
* [http://www.thijsheslenfeld.com/frame.php?catId=1660 Images from two sailing expeditions to Antarctica]
* [http://glacierbliss.com/antarctica.html Pictures from 4 research trips to the McMurdo region]
*[http://www.guardian.co.uk/environment/gallery/2007/jun/05/photography?picture=329977040 World Environment Day 2007 "Melting Ice" image gallery at The Guardian]
*[http://www.expeditionsail.com Expedition sailboat ''Seal''] to Antarctica, many photos
*[http://www.antarctica.ac.uk/bas_research/data/access/fossildatabase/ BAS Online Palaeontology Collection]
*[http://www.usap.gov U.S Antarctic Program Portal]
*[http://www.youtube.com/watch?v=TemK6CF6lF0 Time-lapse images of a year at Scott Base and McMurdo Station area]
*[http://www.antarctica2007.com/ Blog of a sailing trip to the Peninsula]
*[http://www.antarcticadiscovery.com/ Website allows passengers, crew, lecturers and other people tell their story and upload images.]
{{Continents of the world}}
{{Regions of the world}}
[[Category:Antarctica|*]]
[[Category:Continents]]
[[Category:Extreme points of the world]]
[[Category:Lists of coordinates]]
[[Category:Poles]]
[[Category:Special territories]]
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[[nds:Antarktis]]
[[pl:Antarktyda]]
[[pt:Antártica]]
[[ksh:Süüdpool]]
[[ro:Antarctica]]
[[qu:Antartika]]
[[ru:Антарктида]]
[[se:Antárktis]]
[[sm:Anetatika]]
[[sco:Antarcticae]]
[[scn:Antàrtidi]]
[[simple:Antarctica]]
[[sk:Antarktída]]
[[sl:Antarktika]]
[[so:Antiarktis]]
[[sr:Антарктик]]
[[sh:Antarktik]]
[[fi:Etelämanner]]
[[sv:Antarktis]]
[[tl:Antarctica]]
[[ta:அண்டார்டிக்கா]]
[[th:ทวีปแอนตาร์กติกา]]
[[vi:Châu Nam Cực]]
[[tg:Антарктида]]
[[tr:Antarktika]]
[[uk:Антарктида]]
[[ur:انٹارکٹیکا]]
[[wa:Antartike]]
[[yi:אנטארקטיקע]]
[[zh-yue:南極洲]]
[[bat-smg:Antarktėda]]
[[zh:南极洲]]