Transpolar Drift
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Transcript of Transpolar Drift
Transpolar Drift
By: Danielle Holden
Background Moves from
Siberian Coast of Russia through Fram Strait and joins the Eastern Greenland Current
Moves at 1-3 cm/s Depth: 2000 m
Arctic Ocean circulation. Image courtesy of Arctic Monitoring and Assessment Programme (AMAP), Figure 3.29, AMAP (1998).
Ice/Fresh Water Circulation
Beaufort Gyre and Transpolar Drift “exchange” ice between each other
The amount of fresh water transported depends on how much ice was melted in the Arctic 50-70% albedo in Arctic Sensible heat loss into air
and ocean Transpolar Drift collides ice
into Greenland coast: ridge formation and thick ice
The amount of ice exportSource: Torben Königk et al: Fram Strait Ice Export: Variability and its Impact on Climate
Circulation and NAO Positive and Negative
Phases affect the Transpolar Drift differently: Positive phase: creates
westerlies in Arctic, colder air more sea ice, less ice and water transport
Negative phase: weak winds in Arctic, warmer air, less sea ice, more ice and water transport
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Circulation and Vorticity Decadal Oscillations
between (+) and (-) vorticities
Positive and Negative vorticities affect where the current travels. There are 2 paths. Positive Vorticity Phase:
Weak High Pressure in Arctic allows fresh water/sea ice to drift counterclockwise. (RED)
Negative Vorticity Phase: Strong High Pressure forces fresh water clockwise (BLUE)
Transpolar Drift Paths:Source: Mysak: Patterns of Arctic Circulation
References http://www.giub.unibe.ch/klimet/wanner/nao.html http://nsidc.org/seaice/processes/circulation.html Knauss, John A. Introduction to Physical
Oceanography. Long Grove: Waveland Pr Inc, 2005.
Koenigk, T., J. Jungclaus, and U. Mikolajewicz. "Fram Strait Ice Export: Variability and its Impact on Climate." American Geohysical Union (2004).
Mysak, Lawrence A. "Patterns of Arctic Circulation." Science 293 (2001): 1269-270.