The Transpolar Drift Stream is a major

ocean current An ocean current is a continuous, directed movement of sea water generated by a number of forces acting upon the water, including wind, the Coriolis effect, breaking waves, cabbeling, and temperature and salinity differences. Depth contou ...

of the

Arctic Ocean The Arctic Ocean is the smallest and shallowest of the world's five major oceans. It spans an area of approximately and is known as the coldest of all the oceans. The International Hydrographic Organization (IHO) recognizes it as an ocean, ...

, transporting

sea ice Sea ice arises as seawater freezes. Because ice is less dense than water, it floats on the ocean's surface (as does fresh water ice, which has an even lower density). Sea ice covers about 7% of the Earth's surface and about 12% of the world's o ...

from the

Laptev Sea The Laptev Sea ( rus, мо́ре Ла́птевых, r=more Laptevykh; sah, Лаптевтар байҕаллара, translit=Laptevtar baỹğallara) is a marginal sea of the Arctic Ocean. It is located between the northern coast of Siberia, th ...

and the

East Siberian Sea The East Siberian Sea ( rus, Восто́чно-Сиби́рское мо́ре, r=Vostochno-Sibirskoye more) is a marginal sea in the Arctic Ocean. It is located between the Arctic Cape to the north, the coast of Siberia to the south, the New S ...

towards

Fram Strait The Fram Strait is the passage between Greenland and Svalbard, located roughly between 77°N and 81°N latitudes and centered on the prime meridian. The Greenland and Norwegian Seas lie south of Fram Strait, while the Nansen Basin of the Arct ...

. Drift experiments with ships such as the Fram or the

Tara expedition The ''Tara'' expedition is an oceanic research expedition. The boat ''Tara'' is a 36-metre aluminum-hulled schooner, formerly named "Antarctica" then "Seamaster". Designed by the naval architects Olivier Petit and Luc Bouvet, built in France on ...

showed that the drift takes between two and four years. In 1937, Pyotr Shirshov at the

Soviet The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen national ...

drift ice station North Pole-1 described this drift. The stream conveys water in roughly two major routes to the northern

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth#Surface, Earth's surface and about 29% of its water surface area. It is known to separate the "Old World" of Afr ...

at a rate of about per day. Primarily wind-driven, it flows roughly from the northern coast of Russia and Alaska, sometimes curving toward the

Beaufort Sea The Beaufort Sea (; french: Mer de Beaufort, Iñupiaq: ''Taġiuq'') is a marginal sea of the Arctic Ocean, located north of the Northwest Territories, the Yukon, and Alaska, and west of Canada's Arctic islands. The sea is named after Sir ...

before exiting to the Atlantic Ocean. It has been cited as a major factor in the North Atlantic oscillation and

Arctic oscillation The Arctic oscillation (AO) or Northern Annular Mode/Northern Hemisphere Annular Mode (NAM) is a weather phenomenon at the Arctic pole north of 20 degrees latitude. It is an important mode of climate variability for the Northern Hemisphere. The s ...

atmospheric changes. The drift typically takes one of two paths before exiting into the northern Atlantic Ocean. On decadal and longer timescales, the North Atlantic oscillation (NAO) and the Arctic oscillation (AO) indices affect the flow pattern of the transpolar drift stream. During times of positive NAO (NAO+) and positive AO (AO+), there is a weak Arctic high and the associated surface winds produce a cyclonic (anti-clockwise) ice drift motion in eastern Arctic Ocean. In this case, the drift flows from the Laptev Sea towards the Beaufort Sea before exiting the Arctic Ocean through the Fram Strait. Conversely, during periods of NAO- and AO-, there is a strong Arctic high and ice motion flows in an anticyclonic (clockwise) motion in the Eurasian Basin. In this phase, the drift flows directly from the Laptev Sea through the Fram Strait.

References

* Althoff, William F. ''Drift Station: Arctic Outposts of Superpower Science''. Potomac Books Inc. 2007, Dulles, Virginia. p. 51 * Mysak, Lawrence A
"Patterns of Arctic Circulation"
''Science''. New Series, Vol. 293, No. 5533 (Aug. 17, 2001), pp. 1269–1270. Currents of the Arctic Ocean Articles containing video clips {{Arctic-stub de:Eisdrift#Eisdrift in der Arktis

See also

References