1. Transpolar Drift By: Danielle Holden

2. Background G Moves from Siberian Coast of Russia through Fram Strait and joins the Eastern Greenland Current G Moves at 1-3 cm/s G Depth: 2000 m Arctic Ocean circulation. Image courtesy of Arctic Monitoring and Assessment Programme (AMAP), Figure 3.29, AMAP (1998).

3. Ice/Fresh Water Circulation G Beaufort Gyre and Transpolar Drift “exchange” ice between each other G The amount of fresh water transported depends on how much ice was melted in the Arctic G 50-70% albedo in Arctic G Sensible heat loss into air and ocean G Transpolar Drift collides ice into Greenland coast: ridge formation and thick ice G Beaufort Gyre and Transpolar Drift “exchange” ice between each other G The amount of fresh water transported depends on how much ice was melted in the Arctic G 50-70% albedo in Arctic G Sensible heat loss into air and ocean G Transpolar Drift collides ice into Greenland coast: ridge formation and thick ice The amount of ice export Source: Torben Königk et al: Fram Strait Ice Export: Variability and its Impact on Climate

4. Circulation and NAO G Positive and Negative Phases affect the Transpolar Drift differently: G Positive phase: creates westerlies in Arctic, colder air more sea ice, less ice and water transport G Negative phase: weak winds in Arctic, warmer air, less sea ice, more ice and water transport

5. Circulation and Vorticity G Decadal Oscillations between (+) and (-) vorticities G Positive and Negative vorticities affect where the current travels. There are 2 paths. G Positive Vorticity Phase: Weak High Pressure in Arctic allows fresh water/sea ice to drift counterclockwise. (RED) G Negative Vorticity Phase: Strong High Pressure forces fresh water clockwise (BLUE) G Decadal Oscillations between (+) and (-) vorticities G Positive and Negative vorticities affect where the current travels. There are 2 paths. G Positive Vorticity Phase: Weak High Pressure in Arctic allows fresh water/sea ice to drift counterclockwise. (RED) G Negative Vorticity Phase: Strong High Pressure forces fresh water clockwise (BLUE) Transpolar Drift Paths: Source: Mysak: Patterns of Arctic Circulation

6. References G http://www.giub.unibe.ch/klimet/wanner/nao.html http://www.giub.unibe.ch/klimet/wanner/nao.html G http://nsidc.org/seaice/processes/circulation.html http://nsidc.org/seaice/processes/circulation.html G Knauss, John A. Introduction to Physical Oceanography. Long Grove: Waveland Pr Inc, 2005. G Koenigk, T., J. Jungclaus, and U. Mikolajewicz. "Fram Strait Ice Export: Variability and its Impact on Climate." American Geohysical Union (2004). G Mysak, Lawrence A. "Patterns of Arctic Circulation." Science 293 (2001): 1269-270. G http://www.giub.unibe.ch/klimet/wanner/nao.html http://www.giub.unibe.ch/klimet/wanner/nao.html G http://nsidc.org/seaice/processes/circulation.html http://nsidc.org/seaice/processes/circulation.html G Knauss, John A. Introduction to Physical Oceanography. Long Grove: Waveland Pr Inc, 2005. G Koenigk, T., J. Jungclaus, and U. Mikolajewicz. "Fram Strait Ice Export: Variability and its Impact on Climate." American Geohysical Union (2004). G Mysak, Lawrence A. "Patterns of Arctic Circulation." Science 293 (2001): 1269-270.