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Antarctica

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                                                       CAPTION: Antarctica

                                    ( Antarctic Treaty Secretariat emblem)

                                                   Location of Antarctica.
        Area 14,000,000 km² (5,405,430 mi²) (280,000 km² (108,108 mi²)
                   ice-free, 13,720,000 km² (5,297,321 mi²) ice-covered)
                                         Population ~1000 (none permanent)
                                                                Government
      – Executive Secretary governed by the Antarctic Treaty Secretariat
                                                            Johannes Huber
     Partial Territorial claims (frozen - figuratively and literally) Flag
                                                   of Argentina  Argentina
                                              Flag of Australia  Australia
                                                      Flag of Chile  Chile
                                                    Flag of France  France
                                          Flag of New Zealand  New Zealand
                                                    Flag of Norway  Norway
                                    Flag of United Kingdom  United Kingdom
                  Reserved the right to make claims Flag of Russia  Russia
                                      Flag of United States  United States
                                                          Internet TLD .aq
                                                         Calling Code +672

   Antarctic Peninsula glacier.
   Enlarge
   Antarctic Peninsula glacier.

   Antarctica is the southernmost continent and includes the South Pole.
   Geographic sources disagree as to whether it is surrounded by the
   Southern Ocean or the South Pacific Ocean, South Atlantic Ocean, and
   Indian Ocean. It is divided by the Transantarctic Mountains. On
   average, it is the coldest, driest, and windiest continent and has the
   highest average elevation of all the continents. At 14.425 million km²,
   Antarctica is the third-smallest continent after Europe and Australia;
   98% of it is covered in ice. Because there is little 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
   Antarctica has never had an indigenous population. Only cold-adapted
   plants and animals survive there, including penguins, fur seals,
   mosses, lichens, and many types of algae. The name "Antarctica" comes
   from the Greek ανταρκτικός (antarktikos), meaning "opposite the
   Arctic."

   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 Russian
   expedition of 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
   isolated location.

   The Antarctic Treaty was signed in 1959 by 12 countries. 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.

History

   Mount Herschel, Antarctica
   Enlarge
   Mount Herschel, Antarctica

   Belief in the existence of a Terra Australis — a vast continent located
   in the far south of the globe to "balance" the northern lands of
   Europe, Asia and north Africa — had existed since Ptolemy suggested the
   idea in order to preserve symmetry of landmass 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
   "Antarctica," geographers believed that the continent was much larger
   than its actual size.

   European maps continued to show this land until Captain James Cook's
   ships, HMS Resolution and Adventure, crossed the Antarctic Circle on
   January 17, 1773 and again in 1774. 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, NASA, the University of California, San Diego, and
   other sources), ships captained by three men sighted Antarctica in
   1820: Fabian von Bellingshausen (a captain in the Russian Imperial
   Navy), Edward Bransfield (a captain in the British Navy), and Nathaniel
   Palmer (an American sealer out of Stonington, Connecticut). Von
   Bellingshausen supposedly 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 km (20 miles) of the Antarctic mainland and saw ice fields there.

   In 1841, explorer James Clark Ross passed through what is now known as
   the Ross Sea and discovered Ross Island. 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.
   The Endurance at night during Ernest Shackleton's Imperial
   Trans-Antarctic Expedition in 1914.
   Enlarge
   The Endurance at night during Ernest Shackleton's Imperial
   Trans-Antarctic Expedition in 1914.

   During an 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. In addition, Shackleton himself and
   three other members of his expedition made several firsts in December
   1908 - February 1909: first humans to traverse the Ross Ice Shelf, the
   first humans to traverse the Transantarctic Mountain Range (via the
   Beardmore Glacier), and the first humans to set foot on the South Polar
   Plateau. On December 14, 1911, a party 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.

   Richard Evelyn Byrd led several voyages to the Antarctic by plane in
   the 1930s and 1940s. He is credited with implementing mechanized land
   transport and conducting extensive geological and biological research.
   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 Dufek successfully landed an aircraft there.

Geography

   A satellite composite image of Antarctica.
   Enlarge
   A satellite composite image of Antarctica.
   Maritime Antarctica.
   Enlarge
   Maritime Antarctica.
   Size comparison Europe-Antarctica.
   Enlarge
   Size comparison Europe-Antarctica.

   Most of Antarctica is located south of the Antarctic Circle, surrounded
   by the Southern Ocean. It is the southernmost land mass and comprises
   more than 14 million km², making it the fifth-largest continent. The
   coastline measures 17 968 km (11,160 miles) and is mostly characterized
   by ice formations, as the following table shows:

   CAPTION: Coastal types around Antarctica (Drewry, 1983)

                         Type                        Frequency
   Ice shelf (floating ice front)                          44%
   Ice walls (resting on ground)                           38%
   Ice stream/outlet glacier (ice front or ice wall)       13%
   Rock                                                     5%
                         Total                            100%

   Physically, it 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 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. The ice
   sheet is, on average, 2.5 kilometers (1.6 miles) thick. The continent
   has approximately 90% of the world's fresh water, in the form of ice.
   If all of this ice were melted sea levels would rise about 61m (200
   feet). In most of the interior of the continent precipitation is very
   low, down to 20 mm/yr; in a few " blue ice" areas precipitation is
   lower than mass loss by sublimation and so the local mass balance is
   negative. In the 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, ocean
   levels would rise by several meters in a relatively geologically short
   period of time, perhaps a matter of centuries. Several Antarctic ice
   streams, which account for about 10% of the ice sheet, flow to one of
   the many Antarctic ice shelves.
   Mt. Erebus, an active volcano on Ross Island.
   Enlarge
   Mt. Erebus, an active volcano on Ross Island.

   Vinson Massif, the highest peak in Antarctica at 4892 meters
   (16,050 feet), is located in the Ellsworth Mountains. Although
   Antarctica is home to many volcanoes, only Mt. Erebus is active. Mount
   Erebus, located in Ross Island, is the southernmost active volcano.
   There was 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. 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.

   Antarctica is home to more than 70 lakes 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 lakes. It is believed that the lake has been sealed off for
   35 million years. There is some evidence that Vostok's waters may
   contain microbial life. The sealed, frozen surface of the lake shares
   similarities with Jupiter's moon Europa. Confirming that life can
   survive in Lake Vostok strengthens the argument for life on the
   satellite.

Geology

Geological history and paleontology

   More than 170 million years ago, Antarctica was part of the
   supercontinent Gondwana. Over time Gondwana broke apart and Antarctica
   as we know it today was formed around 25 million years ago.

Paleozoic era (540-250 Mya)

   Survey route.
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   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 sandstones, limestones and shales were deposited. East
   Antarctica was at the equator, where sea-floor invertebrates and
   trilobites flourished in the tropical seas. By the start of the
   Devonian period (416 Mya) Gondwana was in more southern latitudes and
   the climate was cooler, though fossils of land plants are known from
   this time. Sand and silts were laid down in what is now the Ellsworth,
   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 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.

Mesozoic era (250-65 Mya)

   Bransfield Strait.
   Enlarge
   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 cycads were plentiful during this period, as were
   reptiles such as Lystrosaurus. In West Antarctica conifer forests
   dominated through the entire Cretaceous period (146-65 Mya), though
   Southern beech began to take over at the end of this period. Ammonites
   were common in the seas around Antarctica, and dinosaurs were also
   present, though only two Antarctic dinosaur species ( Cryolophosaurus
   from the 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)

   Africa separated from Antarctica around 160 Mya, followed by India 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 and the first ice began to appear. Around 23
   Mya, the Drake Passage between Antarctica and South America 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.

Geology of present-day Antarctica

   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 was no longer depressing the landmass.
   Enlarge
   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 was no longer depressing the landmass.
   Port Lockroy Museum.
   Enlarge
   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 have
   begun to reveal the structures beneath the ice.

   Geologically, West Antarctica closely resembles the Andes of South
   America. 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 old, dating from the Precambrian
   era, with some rocks formed more than 3 billion years ago. It is
   composed of a metamorphic and igneous platform which is the basis of
   the continental shield. On top of this base are various more modern
   rocks, such as sandstones, limestones, coal and shales laid down during
   the Devonian and Jurassic periods to form the Transantarctic Mountains.
   In coastal areas such as Shackleton Range and Victoria Land some
   faulting has occurred.

   The main mineral resource known on the continent is coal. 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 and natural gas fields 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

   The Blue ice covering Lake Fryxell, in the Transantarctic Mountains,
   comes from glacial meltwater from the Canada Glacier and other smaller
   glaciers.
   Enlarge
   The Blue ice covering Lake Fryxell, in the Transantarctic Mountains,
   comes from glacial meltwater from the Canada Glacier and other smaller
   glaciers.

   Antarctica is the coldest place on Earth. It is a frozen desert with
   little precipitation; the South Pole itself receives almost none.
   Temperatures reach a minimum of between -85 °C and -90 °C (-121 °F and
   -130 °F) in the winter and about 20 °C (30 °F) higher in the summer
   months. Sunburn is often a health issue as the snow surface reflects
   over 90% of the sunlight falling on it. Eastern Antarctica is colder
   than its western counterpart because of higher elevation. Weather
   fronts rarely penetrate far into the continent, leaving the centre 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 inches) in 48 hours have been
   recorded.
   Mountain glaciation.
   Enlarge
   Mountain glaciation.

   At the edge of the continent, strong katabatic winds 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 at the South Pole than is received at the equator
   in an equivalent period.

   Antarctica is colder than the Arctic for two reasons. First, much of
   the continent is more than 3 km 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.
   Tabletop icebergs in Antarctica.
   Enlarge
   Tabletop icebergs in Antarctica.

Population

   Antarctica has no permanent residents, but a number of governments
   maintain permanent research stations throughout the continent. The
   number of people conducting and supporting scientific research and
   other work on the continent and its nearby islands varies from
   approximately 4000 in summer to 1000 in winter. Many of the stations
   are staffed around the year.
   Two researchers studying plankton through microscopes.
   Enlarge
   Two researchers studying plankton through microscopes.

   The first semi-permanent inhabitants of regions near Antarctica (areas
   situated south of the Antarctic Convergence) were English and American
   sealers who used to spend a year or more on South Georgia, from 1786
   onward. During the whaling era, which lasted until 1966, the population
   of that island varied from over 1000 in the summer (over 2000 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, 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 adopted British
   citizenship in 1910, and his family.
   Field work.
   Enlarge
   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 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.

   Emilio Marcos Palma was the first person born on the Antarctic
   mainland, at Base Esperanza in 1978, his parents being sent there along
   with seven other families by the Argentinean government to determine if
   family life was suitable in the continent. In 1986, Juan Pablo Camacho
   was born at the Presidente Eduardo Frei Montalva Base, becoming the
   first Chilean born in Antarctica. Several bases are now home to
   families with children attending schools at the station.

Flora and fauna

Flora

   More than 200 species of lichens are known in Antarctica.
   Enlarge
   More than 200 species of lichens 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 mosses and liverworts. The
   autotrophic community is made up of mostly protists. The flora of the
   continent largely consists of lichens, bryophytes, 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 approximately 50 species
   of bryophytes, such as mosses. Seven hundred species of algae exist,
   most of which are phytoplankton. Multicolored snow algae and diatoms
   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).

Fauna

   Land fauna is nearly completely invertebrate. Invertebrate life
   includes microscopic mites, lice, nematodes, tardigrades, rotifers, and
   springtails. The midge, just 12 mm in size, is the largest land animal
   in Antarctica. The Snow Petrel is one of only three birds that breed
   exclusively in Antarctica and have been seen at the South Pole.
   Emperor Penguins in Ross Sea, Antarctica.
   Enlarge
   Emperor Penguins in Ross Sea, Antarctica.

   A variety of marine animals exist and rely, directly or indirectly, on
   the phytoplankton. Antarctic sea life includes penguins, blue whales,
   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 Rockhopper penguin has
   distinctive feathers around the eyes, giving the appearance of
   elaborate eyelashes. King penguins, Chinstrap penguins, and Gentoo
   Penguins 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 congregates in large schools, is the keystone
   species of the ecosystem of the Southern Ocean, and is an important
   food organism for whales, seals, leopard seals, fur seals, squid,
   icefish, penguins, albatrosses and many other birds.

   The passing of the Antarctic Conservation Act brought several
   restrictions to 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. Despite these new
   acts, unregulated and illegal fishing, particularly of Patagonian
   toothfish, remains a serious problem. The illegal fishing of toothfish
   has been increasing, with estimates of 32,000 tonnes in 2000.

Politics

   Resupply by the Uruguayan Navy vessel 'Vanguardia'.
   Enlarge
   Resupply by the Uruguayan Navy vessel 'Vanguardia'.

   As the only uninhabited continent, Antarctica has no government and
   belongs to no country. Various countries claim areas of it but these
   claims are typically not recognized by others. 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.

   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 shelves south of 60°S. The
   treaty was signed by 12 countries, including the Soviet Union 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 Antarctica,
   such as the establishment of military bases and fortifications, the
   carrying out of military manoeuvres, or the testing of any type of
   weapon. Military personnel or equipment are only permitted for
   scientific research or for other peaceful purposes. The only documented
   large-scale land military maneuver was Operation NINETY, undertaken ten
   years before the Antarctic Treaty by the Argentine military.

   The United States military issues the Antarctica Service Medal to
   military members or civilians who perform research duty on the
   Antarctica continent. The medal includes a "wintered over" bar issued
   to those who remain on the continent for two complete six-month
   seasons.Unlike other states, the United States has made no territorial
   claim in Antarctica nor does it recognize the claims of any other
   state.

Antarctic territories

   Territorial claims of Antarctica.
   Enlarge
   Territorial claims of Antarctica.

   Country Territory Claim limits Date
   Flag of Argentina  Argentina Argentine Antarctica 25°W to 74°W 1943
   Flag of Australia  Australia Australian Antarctic Territory 160°E to
   142°2′W and 136°11′W to 44°38′E 1933
   Flag of Chile  Chile Antarctic Chilean Territory 53°W to 90°W 1940
   Flag of France  France Adelie Land 142°2′E to 136°11′E 1924
   Flag of New Zealand  New Zealand Ross Dependency 150°W to 160°E 1923
   Flag of Norway  Norway Queen Maud Land 44°38′E to 20°W 1939
   Peter I Island 68°50′S 90°35′W 1929
   Flag of United Kingdom  United Kingdom British Antarctic Territory 20°W
   to 80°W 1908
   NONE Unclaimed territory 90°W to 150°W

   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 20°E to 10°W, overlapping
   Norway's claim.

Economy

   The illegal capture and sale of the Patagonian toothfish has led to
   several arrests. Pictured here is the Antarctic toothfish, a sister
   species.
   Enlarge
   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, hydrocarbons, iron ore, platinum, copper, chromium,
   nickel, gold and other minerals have been found, they exist in
   quantities too small 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 add a 50-year
   ban on mining until the year 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.
   Antarctic postal services.
   Enlarge
   Antarctic postal services.

   Small-scale tourism has existed since 1957 and is currently
   self-regulated by International Association of Antarctic Tour Operators
   (IAATO). However, not all vessels have joined the IAATO. Several ships
   transport people into Antarctica for specific scenic locations. A total
   of 27,950 tourists visited in the 2004-05 Antarctic summer with nearly
   all of them coming from commercial ships. The number is predicted to
   increase to over 80,000 by 2010. There has been some recent concern
   over the adverse environmental and ecosystem affects caused by the
   influx of visitors. A call for stricter regulations for ships and a
   tourism quota have been made by both environmentalists and scientists.
   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, and resumed from Australia in the
   mid-1990s.

Transport

   Transport on the continent has transformed from heroic explorers
   crossing the isolated remote area of Antarctica by foot to a more open
   area due to human technologies enabling more convenient and faster
   transport by land and predominantly air and water.

Research

   A full moon and 25-second exposure allowed sufficient light into this
   photo taken at Amundsen-Scott South Pole Station during the long
   Antarctic night. The new station can be seen at far left, power plant
   in the center and the old mechanic's garage in the lower right.
   Enlarge
   A full moon and 25-second exposure allowed sufficient light into this
   photo taken at Amundsen-Scott South Pole Station during the long
   Antarctic night. The new station can be seen at far left, power plant
   in the centre and the old mechanic's garage in the lower right.

   Each year, scientists from 27 different nations conduct experiments not
   reproducible in any other place in the world. In the summer more than
   4000 scientists operate research stations; this number decreases to
   nearly 1000 in the winter. The McMurdo Station is capable of housing
   more than 1000 scientists, visitors, and tourists.

   Researchers include biologists, geologists, oceanographers, physicists,
   astronomers, glaciologists, and meteorologists. Geologists tend to
   study plate tectonics in the Arctic region, 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, seasonal snow, glaciers,
   and ice sheets. 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 in Amundsen-Scott South Pole Station are able to study
   the celestial dome and cosmic microwave background radiation because of
   the polar's thin ozone layer due lack of sunlight and the location's
   dry, cold environment. Antarctic ice serves as both the shield and the
   detection medium for the largest neutrino telescope in the world, built
   2 km below Amundsen-Scott station.

   Since the 1970s an important focus of study has been the ozone layer in
   the atmosphere above Antarctica. In 1985 3 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 square kilometers. In 2002 significant
   areas of ice shelves disintegrated in response to regional warming.

Meteorites

   Antarctic meteorite, named ALH84001, from Mars.
   Enlarge
   Antarctic meteorite, named ALH84001, from Mars.

   Meteorites from Antarctica are an important area of study of material
   formed early in the solar system; most are thought to come from
   asteroids, but some may have originated on larger planets. The first
   meteorites found in Antarctica were in 1912. In 1969 the Japanese
   discovered nine meteorites in Antarctica. 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 relatively well preserved.

   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 centre 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.

   In 2006 a team of researchers from Ohio State University used gravity
   measurements by NASA's GRACE satellites to discover the 300-mile-wide
   Wilkes Land crater, which probably formed about 250 million years ago.

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