The Antarctic



The Antarctic is a continent situated all around the South Pole. It is the coldest place of the world, it is almost entirely covered by ice. It is the fifth largest continent, after Asia, Africa, North America and South America. However, it is the least populated. 25 times larger than France, it is constituated of two parts :

* in the East, a plateau of approximately 10 million of km² (formely incorporated in Australia)
* in the West, the Antarctic Peninsula, forming the prolongation
of the Andes Cordillera

Seen by satellite

It is the chain of the Transantarctiques Mounts, 2 500 km length, which separates them. The icecap which almost entirely covers it, 59 000 km², exceed sometimes 4 500 m thickness, and constitutes 90% of fresh water of the globe. Some icebergs can exceed the size of Corsica.

The winter, the temperatures can reach -70°C in the grounds and -35°C on the coasts. The summer, they oscillate between -35°C in the grounds and 0°C on the coasts.
The continent holds the world record of the lowest temperature, with -89°C at the base of Vostok, Russian base installed in 1957.

In spite of all the snow and the ice which the continent contains, the Antarctic is regarded as a desert, because annual precipitations, reaching a maximum to 50 mm, are comparable to those of Sahara.

Its history is very related to the many assumptions concerning the shape of the Earth.

Most of sources agree to affirm that it is Aristote who names the first this continent. Indeed, the Greeks think at the time that the Earth being a symmetrical sphere, it needs necessarily a point of balance on both sides of Ecuador : the Arctic ("Arktos" in Greek) and the Antarctic ("Antarktos" in Greek). Arktos means "bear", submit the matter to stars group indicating North, still called today "Great Bear".

In IInd century, Ptolémée, Greek astronomer, is persuaded that the continent exists, so that to affirm that these grounds are inhabited and cultivated, but remain inaccessible to the remainder of the Earth on account of a large insuperable strip of land sheltering monsters.

But in Middle Ages, scientists give up thoughts on this continent, finding strange that God forgot a part of his Creation on these grounds so moved back. One starts to reconsider that the Earth is flat, which excludes the existence from the Antarctic.

One reconsiders there starting from XVth century, when Bartolomeu Dias de Noveas and Vasco de Gama discover new grounds. The latter outline the Cape of Good Hope, in the South of Africa and thus refute the assumption of a continent more in the South. Nevertheless, when Ferdinand Magellan outlines the South of the American continent, he discovers that there is there a strait difficult to cross, and beyond whose a thick snow cover appears under a very cold climate.

When Francis Drake is sent by the english government to explore the Pacific in the years 1570, he sees penguins on an island.

It's finally in XVIIth century, after having undergone storms by crossing Cape Horn, that some navigators fail themselves in the Antarctic. They see there mountains covered with snow and ice, and appearing rather hostile and especially very cold.

And it is finally James Cook who achieves the goal in the years 1770. During several months, he skirts the glaciers of the Antarctic to find a channel of access in order to take possession of the grounds. He succeeds in reaching the continent. He can also affirm with certainty that it is impossible that the continent is inhabited. Nevertheless, he notices the presence of many colonies of seals and whales, which attracts the merchants a few years later. In XIXth century, many boats come to fish the seal along banks of the continent.

It is on the 21th of January 1840 that French explorers, commanded by Dumont d'Urville plant their flag on the antarctic grounds. A few days later, it is the turn of the American fleet of Charles Wikles succeed in doing it. The discovery is then controverted. The first scientific expedition is sent in 1839 by the English, thanks to an association between the British Association for the Avancement of Science and the Royal Society. It includes doctors, naturalists and botanists. In 1928, George Wilkins flies over the continent for the first time. In 1947, the United States organizes an expedition of 4 000 persons with 13 boats and 23 aeroplanes to chart the littoral. The Treaty on the Antarctic is signed on the 1st of December 1959 in Washington by 12 countries : Argentina, Australia, Belgium, Chile, France, Japan, New Zealand, Norway, South Africa, Russia, the United Kingdom, Northern Ireland and the United States. At the present time, 44 countries signed it.

As a geographical area of polar climate, so particularly not very favourable to the life and to the human activity, this continent is the only one not to have on its ground Sovereign state. The Treaty on the Antarctic, signed in 1959 (seen previously), prevent the annexation of this continent by a State whatever it is. It recognizes the continent like a ground favourable to the scientific research, and within this framework, to the international co-operation.

However, diverse countries, by geographical proximity of their metropolis or by interest geostrategic or economic within sight of probable natural resources which involves its subsoil, claim portions. In some cases, these portions are even claimed by several countries. Most of portions are kinds of sections starting of the South Pole, going to the ocean, and whose edges are meridian lines. For example, the Terre Adélie for France.

Some countries maintain in their area a permanent or semi-permanent human presence, in  bases of essentially scientific vocation. These bases are supplied during the court polar summer by ships, which can approach to the coasts when the pack-ice melted partly. It is about Argentina, Chile, France, the United Kingdom, Norway, New Zealand and Australia.

The fauna

In the grounds, one finds only very few animals, which approach more of microscopic organisms.

In the Antarctic Ocean some species particularly of birds forming an enormous biomass cohabit thanks to waters very rich in nutriments and in oxygen. The separation with the others oceans is a true frontier of fog where the temperature goes on average from 6 to 16ºC in few km.



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