Observations of turbulent dissipation in the Amundsen Sea Embayment, Antarctica

Yvonne Firing, NOC, Southampton Cambridge Fluids Network - fluids-related seminars 10 May 2017 11:00am British Antarctic Survey, Innovation Centre, Seminar Room 2 Microstructure and finestructure observations are used to investigate the spatio-temporal distribution and drivers of turbulence in the Amundsen Sea Embayment, Antarctica. Microstructure observations collected in austral summer 2014 show low background levels of turbulent dissipation (10^-10 W/kg) over most of the continental shelf below the surface layer, with some elevated values near the shelfbreak and near topography, and greatly elevated values near the ice shelf front. Turbulent energy dissipation levels are correlated with finestructure horizontal and vertical kinetic energy associated with internal waves, as computed from co-located lowered acoustic Doppler current profiler (ADCP) profiles. Finestructure kinetic energy from four two-year and two one-year moored ADCP records varies by up to an order of magnitude in time; values are higher in the summer at most sites, but exhibit wintertime peaks at one instrument sampling the thermocline.