OS54A-08:
Changes in the Canada Basin: Results From Beaufort Gyre Observing Program/Joint Ocean Ice Studies Expeditions, 2003-2014.
Friday, 19 December 2014: 5:45 PM
William James Williams1,2, Andrey Yu Proshutinsky3, Richard A Krishfield3, Mary-Louise E. Timmermans4, Michiyo Yamamoto-Kawai5, William Li6, Sarah Zimmermann2, Jenny Hutchings7, Fiona McLaughlin2 and Eddy Carmack2, (1)Organization Not Listed, Washington, DC, United States, (2)Fisheries and Oceans Canada, Institute of Ocean Sciences, Sidney, BC, Canada, (3)WHOI, Woods Hole, MA, United States, (4)Yale University, New Haven, CT, United States, (5)Tokyo Univ Marine Sci &Tech, Tokyo, Japan, (6)Fisheries and Oceans Canada, Bedford Institute of Oceanography, Dartmouth, Canada, (7)Oregon State University, Corvallis, OR, United States
Abstract:
Annual expeditions, that make use of ships, moorings and ice tethered platforms, have monitored oceanographic conditions in the Beaufort Gyre Region of the Canada Basin since 2003. These basin-wide surveys, together with available earlier data, show linkages between the physical, geo-chemical and ecosystem components during a period of rapid change, largely forced by increased multi-year ice melt and a prolonged anticyclonic phase of the Arctic Ocean circulation. The resulting Ekman convergence has led to a progressive accumulation of river and ice-melt-derived freshwater within the gyre, an increase in surface stratification and depression of the halocline. These changes in physical state have led to a decrease in aragonite saturation state, a deepening of the top of the nutricline and subsurface chlorophyll maximum and a shift in phytoplankton size spectra. Recent years have shown a slight relaxation of the Beaufort Gyre, in addition to large variation in ice cover, leading to informed speculation that the gyre may now be poised to release some of its accumulated freshwater as a salinity anomaly into the global system.
