All About Antarctica

Antarctica, unlike any other continent, was postulated to exist long before it was actually discovered. The ancient Greeks, beginning with Pythagoras in c. 530B.C. believed the Earth to be round, an idea Aristotle supported and refined further, suggesting that the symmetry of a sphere demanded that the Earth’s inhabited northern region should be balanced by an equally inhabited southern region. This idea of earthly balance gave rise to the name Antarktos, or Antarctica, which means "opposite Artkos" the constellation in the northern sky, also meaning "opposite to the Arctic".

world chart

Fifth largest of the Earth’s seven continents, Antarctica is the southernmost, coldest, windiest, driest, highest and most remote continent. Despite early Greek theory, it was the last continent to be discovered in the early 19th Century. If anything, exploration proved the disexistence of Antarctica, with many expeditions sailing entirely past Antarctica. However, the Greek historian Herodotus recorded as early as 700 BC a Phoenician fleet sailed from the Red Sea south along the African coast and around Cape Agulthas to the Straits of Gibraltar; and in 650 AD, according to Rarotongan legend, a Polynesian navigator named Ui-te-Rangiora sailed so far south that he reached a place where the sea was frozen.

Scientific expeditions and seal hunters had explored only fragments of Antarctica’s coast by the end of the 19th century, while the interior remained unknown. Explorers first reached the South Pole in 1911, and the first permanent settlements--"scientific stations“--were established in early 1940s, with many more established during the International Geophysical Year 1957-58.

Antarctic claim

Seven nations (Argentina, Australia, Britain, Chile, France, New Zealand and Norway) claimed territory in Antarctica. Other nations, including the United States and Russia, do not acknowledge these territorial claims. Since 1961, the continent has been administered under the Antarctic Treaty, an international agreement to preserve the continent for peaceful scientific study.

About 1 percent of the continent’s ice-free areas have been surveyed for minerals, and evidence indicates that Antarctica contains rich mineral deposits. It is also believed that deposits of petroleum and natural gas exist in the continental shelf regions, such as the area under the Ross Sea. The signatory nations of the Antarctic Treaty agreed to a 50-year moratorium on commercial mining activity.

Antarctic tourism began in 1958 and has been steadily growing since. In the late 1990’s about 10,000 tourists visited Antarctica annually between November and March.

relative size of earth’s continents

Antarctica lies 1,000 km (600 miles) south of South America, it’s nearest neighbor; 4,000 km (2,500 miles) from Africa; and 2,500 km (1,600 miles) from Australia.

With an area of 14 million sq km (5.4 million sq miles), Antarctica is larger than either Europe or Australia. It’s average elevation of more than 2,000 m (6,500 ft) is over twice that of Asia, the next highest continent. However, much of this mass is ice. Remove the ice and East Antarctica has a landmass about the size of Australia and West Antarctica becomes a collection of islands.

The rocks of East Antarctica are at least 3 billion years old, and the rocks of West Antarctica are relatively new--only 700 million years old. Much of Antarctica’s geologic history remains unknown as the rock record, required to decipher the history, is hidden beneath the continent’s ice blanket. Drilling projects, including ANDRILL, aim to recover rock core from beneath the ice to help uncover the story of Antarctica’s evolution through deep time.

The Antarctic ice sheet has an area of about 13.3 million square km, which is 1.7 times the size of Australia, 1.4 times the size of the U.S. or Europe. It is thicker than 4 km in some locations and on the average is about 2,160 m (7,090 ft) giving a total ice volume estimated to be 29 million cubic km to about 32.4 million cubic km, or about 90% of the world’s ice. If the ice sheet melted, the oceans would rise by 60 m (200 ft).

ice sheet diagram

This enormous amount of ice has formed though the accumulation of snow over millions of years, although the amount of snow deposited in any one year is relatively low. Antarctica is a desert, and is the driest continent on Earth. Because the snow was deposited over many years without melting, different chemicals and gasses that were mixed into the snow and trapped in the ice, providing a natural archive for glaciologists and climatologists to study evidence of past environments and climatic changes. By drilling through the ice sheet and analyzing the ice and air trapped in the bubbles, scientists are able to access an archive of past climate change.

Mean temperature in the Antarctic interior range from -40°C to -70°C during the coldest month, and from -15°C to -35°C during the warmest month. On the coast, temperatures are considerably warmer -15°C to -32°C in winter; and from 5°C to -5°C in the summer.

penguin

Antarctica experiences the strongest winds on the planet: the katabatics, which can achieve velocities of up to 320 km/h. Antarctic blizzards are quite common. During a typical blizzard, very little if any snow actually falls, but rather snow is picked up and blown along the surface by the wind, many times resulting in complete ’whiteouts’.

deschampsia

Some 350 species of lichens, 100 species of mosses and hundreds of species of alage, including 20 species of snow of alage (which form colorful patches of pink, red, yellow or green on areas of permanent snow) live in Antarctica. There are no trees or shrubs and just two species of indigenous vascular plants: Antarctic hairgrass (Deschampsia antarctica) and Antarctic perlwort (Colobanthus quitensis). The Subantarctic Islands have many more diverse floras.

Antarctica’s native animals are all invertebrates, with nearly all terrestrial macrofauna belonging to the phylum Anthropda (including mites, lice springtails, midges and fleas, many of which are parasites of seals and birds).

penguin

Approximately 45 species of birds breed south of the Antarctic Convergence (a line encircling Antarctica where the cold, northward-flowing Antarctic waters sink beneath the relatively warmer waters of the Subantarctic. This line is actually a zone approximately 20 to 30 miles wide, varying somewhat in latitude in different longitudes, extending across the Atlantic, Pacific, and Indian oceans between the 48th and 61st parallels of South latitude. The precise location at any given place and time is made evident by the sudden change in surface temperature, which averages 5° to 10°F (2.8° to 5.5°C). Although the zone is a mobile one, it usually does not stray more than a half degree of latitude from its mean position. It not only separates the two hydrological regions, but also separates areas of distinctive marine life associations and of different climates), including 7 of the 17 living species of penguins. Just a few bird species breed in Antarctica, among them Emperor, Adelie and Gentoo penguins, snow petrels, Antarctic Petrels and South Polar Skuas. The Southern Ocean, by contrast, teems with life. Supporting a wealth of fish, seal, whale and seabird species.

Information compiled by Laura Lacy, Research Support Coordinator, ANDRILL Science Management Office.