Arctic Ocean
See also: Arctic (homonymy)
The Arctic Ocean , or Arctic icy ocean , extends on a surface from 14 090 000 km ², which makes of it smallest Océan. It recovers the whole of the seas located between the North pole and the north of the Europe, the Asia and the America. It communicates with the north of the Atlantic Ocean, receiving great water masses through the Mer of Barents and the Détroit of Fram. It is also in contact with the Pacific Ocean through the Bering Strait.
It is mainly covered by the Banquise, whose extension according to the Saison S. In its central part the ice-barrier varies can make up to 4 m thickness, This thickness is reached by the slip of ice floes the ones on the others.
Climate
Current climate
The polar climate is characterized by the cold persisting and of weak annual variations of temperatures; the winter is characterized by the darkness continues, cold and stable conditions, and a clear sky; the summer is characterized by light of day continues, important moisture and misty time, and the weak cyclones with rain or snow.The winter temperatures are close to -50 ºC because of the strong winds coming from Siberia (Russia); while in summer they can exceed 0 ºC.
History of the climate
According to studies carried out by specialists in the University of Oxford (Great Britain) and in the Royal Netherlands Institute for Sea Research (NIOZ), the Arctic Ocean enjoyed, there is 70 million years, temperatures close to 15 ºC, similar to those of the Mediterranean; and of temperatures of 20 ºC, 20 million years ago.The researchers arrived at this conclusion after having studied organic materials found in muds of small islands of ice of the Arctic Ocean. Although the reasons of such temperatures are not known, the assumption of an greenhouse effect caused by the strong concentration of the Carbon dioxide in the atmosphere. This conclusion is confirmed by scientists of the Université of Michigan (the United States), which affirms that the carbon dioxide rates, a few million years ago, were from three to six times higher than the current content.
It is known that the thickness of the layer of ices of the Arctic Ocean decreased by 40% in the 50 last years and the results indicate that this evolution will continue, the cast iron of the ices should be faster with the passing of years, while leading to the disappearance of those during the summer, with serious effects on the ecological balance of the area and for the habitat of certain species, as the polar bear which needs an ice-barrier to survive and drive out its preys.
Future trend
Researchers predict that in less than 50 years, the Arctic Ocean will be perfectly navigable during the summer. Indeed, the layer of ice which recovers this oceanic mass becomes each meaner year, because of increasingly long duration of strong heats.
Animal life
There exist approximately 400 animal species in the Arctic. Among most known the polar Polar bear or, the largest carnivore in this zone. It can have a mass of 800 kg. Although it nourishes Phoque S and of Poisson S, it is able to him in the event of bad hunting to replace them by foams and Lichen S.Six species of seal live in this ocean, although their number fell since the 19th century because of its natural predator, the polar bear, and of the intensive hunting to which the Man subjected, drives out the purpose of which is to recover the skin and the grease of the animal. Another typical inhabitant of the zone is the Baleine, also threatened and which, currently, is protected from hunting.
One finds also an inhabitant more discrete: the Krill, which plays a big role in the food chain.
External bonds
- the Arctic Icy ocean with the outposts of the total climate change (CNRS)
Be-X-old: Арктычныакіян Simple: Arctic Ocean Zh-min-nan: Pak-ke̍k-iûⁿ
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