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Arctic

2007 Schools Wikipedia Selection. Related subjects: General Geography

   The red line indicates the 10°C isotherm in July, commonly used to
   define the Arctic region border
   The red line indicates the 10°C isotherm in July, commonly used to
   define the Arctic region border
   Satellite image of the Arctic surface
   Satellite image of the Arctic surface

   The Arctic is the region around the Earth's North Pole, opposite the
   Antarctic region around the South Pole. In the northern hemisphere, 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, which means bear. This is due to the
   location of the constellation 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. 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. In climate change research, the
   Arctic region is often considered an early warning system for the
   planet.

Nature

Climate

   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 -37°C
   (-34.6°F) and the coldest recorded temperature is approximately -68°C
   (-90.4°F). Coastal arctic climates are moderated by oceanic influences,
   having generally warmer temperatures and heavier snowfalls than the
   colder and drier interior areas.

Plants

   Since trees cannot grow in the climate, the vegetation of the Arctic
   tundra is composed of plants such as dwarf shrubs, graminoids, herbs,
   lichens and mosses, which are all comparatively close to the ground. As
   one moves northward, the amount of warmth available for plant growth
   decreases considerably. In the northernmost areas plants are at their
   metabolic limits, and small differences in the total amount of summer
   warmth make large differences in the amount of energy available for
   maintenance, growth and reproduction. Colder summer temperatures cause
   the size, abundance, productivity and variety of plants to decrease. In
   the warmest parts of the Arctic, shrubs are common and can reach 2 m (6
   ft) in height; sedges, mosses and lichens can form thick layers. In the
   coldest parts of the Arctic much of the ground is bare, nonvascular
   plants such as lichens and mosses predominate, along with a few
   scattered grasses and forbs (like the arctic poppy).

Animals

     * Polar bears have white fur so they can camouflage in the snow. This
       helps them to sneak up on seals when they’re hungry.
     * The wolverine is part of the weasel family, and lives in holes in
       the ground. Though it is a small animal, it is very powerful.
     * Arctic foxes are hard to spot in the snow because of their thick
       white fur. In the summer, their fur turns a brownish-grey colour.
     * The Ptarmigan is a type of bird which nests in the snowy mountains,
       where they raise their young.
     * Beluga means “white one” in Russian. Adults are white and the young
       are grey. This is so that the young can’t be seen easily by their
       predators. (Type of whale)
     * Some other animals include the Arctic Wolf, Ringed Seal, Lemmings,
       and the Arctic Hare.

Paleo-History

   During the Cretaceous, the Arctic still had seasonal snows, though only
   a light dusting and not enough to permanently hinder plant growth.
   Animals such as Chasmosaurus, Hypacrosaurus, Troodon, and Edmontosaurus
   may have all migrated north to take advantage of the summer growing
   season, and migrated south to warmer climes when the winter came. A
   similar situation may also have been found amongst dinosaurs that lived
   in Antarctic regions, such as Muttaburrasaurus of Australia.

International cooperation and politics

   The Arctic region is a focus of international political interest.
   International Arctic cooperation got underway on a broad scale well
   over ten years ago. The International Arctic Science Committee (IASC),
   hundreds of scientists and specialists of the Arctic Council, the
   Barents Council and its regional cooperation have compiled high quality
   information on the Arctic.

Territorial claims

   On December 20, 2001 Russia made an official submission into the UN
   Commission on the Limits of the Continental Shelf in accordance with
   the United Nations Convention on the Law of the Sea (article 76,
   paragraph 8). In the document it is proposed to establish new outer
   limits of the continental shelf of Russia beyond the previous 200 mile
   zone, but within the Russian Arctic sector. The territory claimed by
   Russia in the submission is a large portion of the Arctic, including
   the North Pole. One of the arguments was a statement, that the
   underwater Lomonosov Ridge and Mendeleev Ridge are extensions of the
   Eurasian continent. In 2002 the UN Commission neither rejected, nor
   accepted the Russian proposal, recommending to carry out additional
   research.

   Canada (citing the Law of the Sea) claims control over the waterways
   throughout its 200-mile zone, which includes the Northwest Passage.
   This claim is not recognized by the United States.

A strategic military region

   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. In the 1950s
   and 1960s, the Arctic was often used by submarines to test new weapons,
   sonar equipment, and depth testing.

   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
   Spitzbergen and Siberia. Increased Russian activity has also been
   detected, though this can be attributed to the Chelyuskin icebreaker
   wreck expeditionary force.

Scientific exploration

   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.

Pollution

   Long-range pollution pathways to the Arctic
   Long-range pollution pathways to the Arctic

   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.

Effects of global warming

Arctic Waters

     * Arctic Ocean
     * Baffin Bay
     * Beaufort Sea
     * Barents Sea
     * Bering Sea
     * Bering Strait
     * Chukchi Sea
     * Davis Strait
     * Denmark Strait
     * East Siberian Sea
     * Greenland Sea
     * Hudson Bay
     * Kara Sea
     * Laptev Sea
     * Nares Strait
     * Norwegian Sea

Arctic Lands

     * Alaska ( USA)
     * Aleutian Islands ( USA)
     * Bjørnøya (Norway)
     * Canadian Arctic Archipelago
     * Diomede Islands (Russia/ USA)
     * Franz Josef Land (Russia)
     * Newfoundland and Labrador (Canada)
     * New Siberian Islands (Russia)
     * Northwest Territories (Canada)
     * Novaya Zemlya (Russia)
     * Nunavik (northern Québec, Canada)
     * Nunavut (Canada)
     * Finnmark (Norway)
     * Greenland (Denmark)
     * Iceland
     * Jan Mayen (Norway)
     * Severnaya Zemlya (Russia)
     * Siberia (Russia)
     * Svalbard (Norway)
     * Yukon (Canada)
     * Wrangel Island (Russia)

The Arctic in Popular Culture

     * Raising the Past by Jeremy Robinson
     * Ice Hunt by James Rollins
     * Deception Point by Dan Brown

   Retrieved from " http://en.wikipedia.org/wiki/Arctic"
   This reference article is mainly selected from the English Wikipedia
   with only minor checks and changes (see www.wikipedia.org for details
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