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The Arctic Ocean, located entirely in the north polar region, is the
smallest of the world's five oceans (after the Pacific Ocean, Atlantic Ocean, Indian Ocean, and Southern
Ocean), and the shallowest.
It occupies a roughly circular basin and covers an area of about 14,090,000 kmē (5,440,000 sq mi). Nearly landlocked, the
ocean is surrounded by the land masses of Europe, Asia, North America, and Greenland and a number of islands, as well as by the Barents,
Beaufort, Chukchi,
Kara, Laptev, East Siberian, Lincoln, Wandel, Greenland, and Norwegian seas. It is connected to the
Pacific Ocean by the Bering Strait and to the Atlantic Ocean through the
Greenland Sea.
An underwater ocean ridge, the Lomonosov ridge, divides the Arctic Ocean
into two basins: the Eurasian, or Nansen, Basin, which is between 4,000 and 4,500 m (13,000 and 15,000 ft) deep, and the North
American, or Hyperborean, Basin, which is about 4,000 m deep. The topography of the ocean bottom is marked by fault-block ridges,
plains of the abyssal zone, ocean deeps, and basins. The average depth of the Arctic Ocean is 1,038 m (3,407 ft) [1] (http://www.marianatrench.com/mariana_trench-oceanography.htm).
The greatest inflow of water comes from the Atlantic by way of the Norwegian Current, which then
flows along the Eurasian coast. Water also enters from the Pacific via the Bering Strait. The East Greenland Current carries the major outflow. Temperature
and salinity vary seasonally as the ice cover melts and freezes. Ice covers most of the ocean surface year-round, causing
subfreezing temperatures much of the time. The Arctic is a major source of very cold air that inevitably moves toward the
equator, meeting with warmer air in the middle latitudes and causing rain and snow. Little marine life exists where the ocean
surface is covered with ice throughout the year. Marine life abounds in open areas, especially the more southerly waters. The
ocean's major ports are the Russian cities of Murmansk and Arkhangelsk (Archangel). The Arctic Ocean is
important as the shortest air route between the Pacific coast of North America and Europe.
Location
Body of water mostly north of the Arctic Circle
Geographic coordinates
90 00 N, 0 00 E
Map references
Arctic Region
Area
- total:14.056 million kmē
- note: includes Back's River, Baffin Bay, Barents Sea, Beaufort Sea, Chukchi Sea, East Siberian Sea, Greenland Sea, Hudson Bay, Hudson Strait,
Kara Sea, Laptev Sea, White Sea, Northwest
Passage and other tributary bodies of water
Area - comparative
Slightly less than 1.5 times the size of the US
Coastline
45,389 km
Climate
Polar climate characterized by persistent cold and relatively narrow
annual temperature ranges; winters characterized by continuous darkness, cold and stable weather conditions, and clear skies;
summers characterized by continuous daylight, damp and foggy weather, and weak cyclones with rain or snow
Terrain
Central surface covered by a perennial drifting polar icepack that averages about 3 meters in thickness, although pressure
ridges may be three times that size; clockwise drift pattern in the Beaufort Gyral Stream,
but nearly straight-line movement from the New Siberian
Islands (Russia) to Denmark
Strait (between Greenland and Iceland); the icepack is surrounded by open seas during the summer, but more than doubles in size during the winter
and extends to the encircling landmasses; the ocean floor is about 50% continental shelf (the highest percentage of any ocean) with the
remainder a central basin interrupted by three submarine ridges (Alpha Cordillera, Nansen Cordillera, and Lomonosov Ridge)
Elevation extremes
- lowest point: Fram Basin
−4,665 m (according to [2] (http://www.marianatrench.com/mariana_trench-oceanography.htm), the Arctic Ocean's Eurasian
Basin depest point is at −5,450 m (17,881 ft))
- highest point: sea level 0 m
Natural resources
Oil and gas fields, placer deposits, polymetallic nodules, sand and gravel aggregates, fish, marine mammals (seals and whales)
Natural hazards
Ice islands occasionally break away from northern Ellesmere
Island; icebergs calved from glaciers in western Greenland and extreme northeastern Canada; permafrost on islands; virtually ice locked from October to June; ships subject to superstructure icing from
October to May
Environment - current issues
Endangered marine species include walruses and whales; fragile ecosystem slow to change and slow to recover from disruptions or damage; thinning polar
icepack; seasonal hole in ozone layer over the North Pole
Reduction of the area of Arctic sea ice will have an effect on the planet's albedo,
thus affecting global warming. Many scientists are presently concerned
that warming temperatures in the Arctic may cause large amounts of fresh, Arctic Ocean meltwater to enter the North Atlantic,
possibly disrupting global ocean current patterns.
Potentially severe changes in the Earth's climate might then ensue.
Geography - note
Major chokepoint is the southern Chukchi Sea (northern access to the
Pacific Ocean via the Bering Strait); strategic location between North
America and Russia; shortest marine link between the extremes of eastern and
western Russia; floating research stations operated by the US and Russia; maximum snow cover in March or April about 20 to 50
centimeters over the frozen ocean; snow cover lasts about 10 months.
Extent of the ice-pack
There is considerable seasonal variation in how much pack ice covers the Arctic
Ocean.
Ports and harbors
Churchill, Manitoba (Canada), Murmansk (Russia), Arkhangelsk (Russia), Dikson (Russia), Prudhoe Bay (US)
Transportation - note
Sparse network of air, ocean, river, and land routes; the Northwest Passage (North America) and Northern Sea Route (Eurasia) are important seasonal
waterways
Exploration
The first surface crossing of the Arctic Ocean was led by Wally Herbert in 1969, in a
dogsled expedition from Alaska to Svalbard with air support. See also Northwest
Passage, Open Polar Sea.
References
Bibliography: Neatby, L. H., Discovery in Russian and Siberian Waters (1973); Ray, L., and Stonehouse, B., eds., The
Arctic Ocean (1982) Thoren, Ragnar, Picture Atlas of the Arctic (1969).
Based on public domain text by US Naval Oceanographer: http://oceanographer.navy.mil/arctic.html
External links
ct:Oceā Ārtic
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