The Arctic is the region around the Earth’s North Pole, opposite the Antarctic region around the South Pole. The Arctic includes the Arctic Ocean (which overlies the North Pole) and parts of Canada, Greenland (a territory of Denmark), Russia, the United States (Alaska), Iceland, Norway, Sweden and Finland. The word Arctic comes from the Greek word arktos (άρκτος) , which means bear. This is due to the location of the constellation (a group of stars) Ursa Major, the “Great Bear”, above the Arctic region.

There are numerous definitions of the Arctic region. The boundary is generally considered to be north of the Arctic Circle (66° 33’N), which is the approximate limit of the midnight sun and the polar night. Other definitions are based on climate and ecology, such as the 10°C (50°F) July isotherm, which roughly corresponds to the tree line in most of the Arctic. Socially and politically, the Arctic region includes the northern territories of the eight Arctic states, including Lapland, although by natural science definitions much of this territory is considered subarctic.

The Arctic region consists of a vast ice-covered ocean (which is sometimes considered to be a northern arm of the Atlantic Ocean) surrounded by treeless, frozen ground. In recent years the extent of the sea ice has declined, and there is some evidence suggesting Arctic water may be ice-free in summer. Some estimates suggest an ice-free summer Arctic by 2040, or 2100 while a more recent study accompanied by unexpected increased melting in summer 2007 estimates as soon as 2013..However according to the Norwegian International Polar Year Secretariat the arctic polar ice cap would be completely gone by summer 2008 Life in the Arctic includes organisms living in the ice, fish and marine mammals, birds, land animals, and human societies.

The Arctic region is a unique area among Earth’s ecosystems. The cultures in the region and the Arctic indigenous peoples have adapted to its cold and extreme conditions.

The Arctic’s climate is characterized by cold winters and cool summers. Precipitation mostly comes in the form of snow. The Arctic’s annual precipitation is low, with most of the area receiving less than 50 cm (20 inches). High winds often stir up snow, creating the illusion of continuous snowfall. Average winter temperatures can be as low as -40°C (-40°F), and the coldest recorded temperature is approximately -68°C (-90°F). Coastal Arctic climates are moderated by oceanic influences, having generally warmer temperatures and heavier snowfalls than the colder and drier interior areas.

The Inuit are the descendants of what anthropologists call the Thule culture, a nomadic people who emerged from western Alaska around 1000 CE and spread eastwards across the Arctic, displacing the related Dorset culture (in Inuktitut, the Tuniit). Inuit legends speak of the Tuniit as “giants”, people who were taller and stronger than the Inuit, but who were easily scared off and retreated from the advancing Inuit. Researchers believe that the Dorset culture lacked dogs, boats and other technologies that gave the expanding Inuit society a large advantage over them. By 1300, the Inuit had settled west Greenland, and finally moved into east Greenland over the following century.

The Tuniit survived in Aivilik, Southampton and Coats Islands, until the beginning of the 20th century. They were known as Sadlermiut (Sallirmiut in the modern spelling). Their population had been ravaged by diseases brought by contact with Europeans, and the last of them fell in a flu epidemic caught from a passing whaler in 1902. The area has since been resettled by Inuit. Genetic research suggests that there was little or no intermarriage between the Tuniit and the Inuit over the thousand years of contact in the Canadian Arctic.

Some countries claim the Arctic has never been under the political control of any nation, although some nations’ militaries have attached a strategic importance to the region. Canada has an outpost in the region (Alert) and has long laid claim to much of the Arctic. Several recent excursions by the Canadian navy have taken place, with more planned to underline Canadian sovereignty in the region. On July 9th, 2007, Canada’s prime minister Stephen Harper announced that Canada will build up to eight armed patrol ships with helicopter pads and a deep water port at a location yet to be disclosed to reassert Canada’s sovereignty over Arctic territories.

In the 1950s and 1960s, the Arctic was often used by submarines to test new weapons, sonar equipment, and depth capability. During the Cold War, the Arctic region was extensively monitored by the United States military and NATO, since it was believed that the first warnings of a nuclear strike from the Soviet Union would have been indicated by ICBMs launched over the North Pole towards the United States. The United States placed such importance on the region that two military decorations, the Arctic Service Ribbon and Coast Guard Arctic Service Medal, were established for military duty performed within the Arctic Circle.

In 2006, Envisat and EOS Aqua revealed a polar route connecting Spitsbergen and Siberia. Increased Russian activity has also been detected, though this can be attributed to the Chelyuskin icebreaker wreck expeditionary force

Since 1937 the whole Arctic region was extensively explored by the Soviet and Russian manned drifting ice stations. Scientific settlements that were established on the drift ice were carried thousands of kilometers by the ice flow.

The Arctic is comparatively clean, although there are certain ecologically difficult localized pollution problems that present a serious threat to people’s health living around these pollution sources. Due to the prevailing worldwide sea and air currents, the Arctic area is the fallout region for long-range transport pollutants, and in some places the concentrations exceed the levels of densely populated urban areas. An example of this is the phenomenon of Arctic haze, which is commonly blamed on long-range pollutants.

The Arctic is especially vulnerable to the effects of global warming as has become apparent in the melting sea ice in recent years. Climate models predict much greater warming in the Arctic than global average.This fact has garnered significant international attention to the region. In particular, there are concerns that Arctic shrinkage, a consequence of melting glaciers and other ice in Greenland, could soon contribute to a substantial rise in sea levels worldwide.A recent study by a research group at Naval Postgraduate School, Monterey, California working with members of Nasa and the Institute of Oceanology at the Polish Academy of Sciences estimate that the Arctic sea could be ice-free in the summer as soon as 2013. The Arctic sea ice melted at an unprecedented rate, well ahead of models, in 2007. See also: Polar ice packs.

Apart from concerns regarding the detrimental effects of cooling in the Arctic, some potential opportunities have gained attention as well. The melting of the ice is making the so-called northwest passage, the shipping routes through the northern-most latitudes, more navigable, raising the possibility that the Arctic region will become a prime trade route. In addition it is believed that the Arctic seabed may contain substantial oil fields which may become accessible if the ice covering them melts.These factors have led to recent international debates as to which nations can claim sovereignty or ownership over the waters of the Arctic. but according to the Norwegian International Polar Year Secretariat the arctic polar ice cap would be completely gone by summer 2008