Arctic Ocean

A spring 2000 decision by the International Hydrographic Organization delimited a fifth world ocean from the southern portions of the Atlantic Ocean, Indian Ocean, and Pacific Ocean. The new ocean extends from the coast of Antarctica north to 60 degrees south latitude which coincides with the Antarctic Treaty Limit. The Arctic Ocean remains the smallest of the world's five oceans (after the Pacific Ocean, Atlantic Ocean, Indian Ocean, and Southern Ocean).

• 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

• 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 (highest percentage of any ocean) with the remainder a central basin interrupted by three submarine ridges (Alpha Cordillera, Nansen Cordillera, and Lomonosov Ridge)

• ice islands occasionally break away from northern Ellesmere Island;
• icebergs calved from glaciers in western Greenland and extreme northeastern Canada;
• permafrost in islands;
• virtually ice locked from October to June;
• ships subject to superstructure icing from October to May

• endangered marine species include walruses and whales;
• fragile ecosystem slow to change and slow to recover from disruptions or damage;
• thinning polar icepack

• 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

• some maritime disputes (see littoral states);
• Svalbard is the focus of a maritime boundary dispute between Norway and Russia [Country Listing] [ The World Factbook Home]