Microstructure Observations of Upward Turbulent Heat Fluxes in the Beaufort Gyre

Elizabeth Fine1, Jennifer A MacKinnon2, Matthew H Alford3, John Mickett4, Madeleine Marie Hamann5, Olavo Badaro Marques1, Gunnar Voet1, Gregory LeClaire Wagner6, Marion S Alberty1 and Algot Peterson7, (1)Scripps Institution of Oceanography, La Jolla, CA, United States, (2)University of California San Diego, La Jolla, CA, United States, (3)Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, United States, (4)University of Washington, Applied Physics Laboratory, Seattle, WA, United States, (5)Scripps Institution of Oceanography, Physical Oceanography, La Jolla, CA, United States, (6)Scripps Institute of Oceanography, La Jolla, CA, United States, (7)Bjerknes Centre for Climate Research, Bergen, Norway
Abstract:
Recent years have seen dramatic reduction of summer Arctic sea ice coverage, particularly in the Western Arctic. Due to this reduction of sea ice, large areas of the Beaufort Sea are now exposed to direct wind forcing during the summer and autumn months. Understanding potentially increased turbulent heat and salt fluxes in this new regime is crucial for accurate climate prediction.

On a 28-day cruise in September 2015 that included direct microstructure measurements, high-resolution lateral tows and a turbulence-measuring profiling mooring, we conducted multiple process studies in the Beaufort Sea aimed at observationally constraining turbulent heat and salt fluxes in the upper ocean, and at developing an understanding of the dynamics that set ocean stratification in the Canada Basin. Preliminary results include observations of shallow turbulent heat fluxes on par with atmospheric heat fluxes and the episodic influence of the warming Atlantic and Pacific layers.