About Antarctica
Antarctica located at the South Pole, Antarctica has no permanent population and no countries. It is reserved for use as a scientific base. Antarctica is the fifth largest continent by land area, and the least populated continent. Antarctica is an island, and is completely surrounded by the Southern Ocean.
High winds, extremely cold temperatures, lack of vegetation, and a very dry desert makes the climate of Antarctica highly inhospitable. Despite this, a number of species have adapted to the environment. This includes seals, penguins, and a number of plants and bacteria.
The only human presence in Antarctica are scientists who live on the island on a temporary basis. It is also possible to visit Antarctica as a tourist.
Antarctica, on average, is the coldest, driest, and windiest continent, and has the highest average elevation of all the continents.[6] Most of Antarctica is a polar desert, with annual precipitation of 20 cm (7.9 in) along the coast and far less inland.[7] The temperature in Antarctica has reached −89.2 °C (−128.6 °F) (or even −94.7 °C (−135.8 °F) as measured from space[8]), though the average for the third quarter (the coldest part of the year) is −63 °C (−81 °F). Anywhere from 1,000 to 5,000 people reside throughout the year at research stations scattered across the continent. Organisms native to Antarctica include many types of algae, bacteria, fungi, plants, protista, and certain animals, such as mites, nematodes, penguins, seals and tardigrades. Vegetation, where it occurs, is tundra.
Antarctica is a de facto condominium, governed by parties to the Antarctic Treaty System that have consulting status. Twelve countries signed the Antarctic Treaty in 1959, and thirty-eight have signed it since then. The treaty prohibits military activities and mineral mining, prohibits nuclear explosions and nuclear waste disposal, supports scientific research, and protects the continent's ecozone. Ongoing experiments are conducted by more than 4,000 scientists from many nations.
History of exploration
Antarctica has no indigenous population, and there is no evidence that it was seen by humans until the 19th century. However, in February 1775, during his second voyage, Captain Cook called the existence of such a polar continent "probable" and in another copy of his journal he wrote: " firmly believe it and it's more than probable that we have seen a part of it"
Geography
Positioned 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, Atlantic, and Indian Oceans, or by the southern waters of the World Ocean. 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:
| 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% |
Geology:
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.
Climate
Antarctica is the coldest of Earth's continents. It used to be ice-free until about 34 million years ago, when it became covered with ice. The coldest natural air temperature ever recorded on Earth was −89.2 °C (−128.6 °F) at the Russian Vostok Station in Antarctica on 21 July 1983.] For comparison, this is 10.7 °C (20 °F) colder than subliming dry ice at one atmosphere of partial pressure, but since CO2 only makes up 0.039% of air, temperatures of less than −140 °C (−220 °F) would be needed to produce dry ice snow in Antarctica. A lower air temperature of −94.7 °C (−138.5 °F) was recorded in 2010 by satellite—however, it may be influenced by ground temperatures and was not recorded at a height of 7 feet (2 m) above the surface as required for the official air temperature records. Antarctica is a frozen desert with little precipitation; the South Pole receives less than 10 cm (4 in) per year, on average. Temperatures reach a minimum of between −80 °C (−112 °F) and −89.2 °C (−128.6 °F) in the interior in winter and reach a maximum of between 5 °C (41 °F) and 15 °C (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. 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.
Population
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 kilometres (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.
Politics
Several countries claim sovereignty in certain regions. While a few of these countries have mutually recognized each other's claims, the validity of these claims is not recognized universally.
New claims on Antarctica have been suspended since 1959, although in 2015 Norway formally defined Queen Maud Land as including the unclaimed area between it and the South Pole. Antarctica's status is regulated by the 1959 Antarctic Treaty and other related agreements, collectively called the Antarctic Treaty System. Antarctica is defined as all land and ice shelves south of 60° S for the purposes of the Treaty System. The treaty was signed by twelve countries including the Soviet Union (and later Russia), the United Kingdom, Argentina, Chile, Australia, and the United States. It set aside Antarctica as a scientific preserve, established freedom of scientific investigation and environmental protection, and banned military activity on Antarctica. This was the first arms control agreement established during the Cold War.
Economy
There is no economic activity in Antarctica at present, except for fishing off the coast and small-scale tourism, both based outside Antarctica.
Although coal, hydrocarbons, 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 economic activity is the capture and offshore trading of fish. Antarctic fisheries in 2000–01 reported landing 112,934 tonnes.
Research
Each year, scientists from 28 different nations conduct experiments not reproducible in any other place in the world. In the summer more than 4,000 scientists operate research stations; this number decreases to just over 1,000 in the winter. McMurdo Station, which is the largest research station in Antarctica, is capable of housing more than 1,000 scientists, visitors, and tourists.
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