As part of the Arctic/Sub-Arctic Ocean Flux (ASOF) and the International PolarYear (IPY) programs, a research project consisting of mooring and analysis workhas studied the ocean and ice fluxes passing through Lancaster Sound, one of thethree main pathways through the Canadian Arctic Archipelago (CAA) since 1998.The aim is to understand the variability in ocean and sea ice volume, heat andfreshwater fluxes passing through the CAA and to determine their relationship tothe ocean and ice budgets of the Arctic Ocean itself and to the circulation andvertical ventilation of the North Atlantic Ocean. Eight years of mooring data havenow been processed and analyzed. The volume, freshwater and heat fluxes exhibitlarge seasonal and interannual variabilities with small fluxes in the fall and earlywinter and large fluxes in the summer. The seasonal mean volume flux estimatesrange from a low of 0.0 Sv in the fall of 1998 to a maximum of 1.3 Sv in thesummer of 2000 (1Sverdrup = 1.0 x 10~6m~3 s~(-1)).It has an 8 year annual mean of0.7 Sv and varies interannually by ±0.3 Sv. Model simulations indicate that fluxesthrough Lancaster Sound make up 40-50% of the fluxes through the entireCanadian Arctic Archipelago, and that they are dependent on the sea leveldifference between the Beaufort Sea and Baffin Bay and on the horizontal densitygradients across the CAA, observations of which are scarce or non-existent.Regression analysis with the Arctic Ocean wind field shows that the fluxesthrough the NW Passage measured in Lancaster Sound are significantly correlatedwith the far field wind forcing in the Beaufort Sea. The northeastward winds in theBeaufort Sea, parallel to the western side of the Canadian Arctic Archipelago,show the highest correlation on monthly to interannual time scales. This result isconsistent with the transport being driven by a sea level difference betweenopposite ends of the NW Passage, and the difference being determined by setupcaused by alongshore winds in the Beaufort Sea.
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