This proposal requests funds to continue analysis of data collected in the Northwest Passage near Resolute, NWT in April/May 1995. The data that was collected consisted of: nearly 1200 vertical profiles of microstructure temperature (T), conductivity (C), and turbulent dissipation rate ((); continuous measurements of the vertical profile of currents with a 300 kHz acoustic doppler current profiler (ADCP); and continuous measurement of T (10 depths) and C (3 depths) from sensors mounted on a mooring. All measurements span the approximate depth range of 2 to 125 m below the ice base, in 150 m of water. The 3-dimensional structure and horizontal phase propagation of the large-amplitude internal gravity waves that are responsible for most of the mixing in this region were determined. A separate study by Cota (Univ. Tennessee) investigates the relative importance of light and nutrient fluxes on the spring growth of ice algal communities. The two-year period covered by this renewal will allow the study of: generation, evolution, and dissipation of large-amplitude, non-linear waves (with Ingram and Marsden); surface mixing under the smooth, land-fast sea ice (with McPhee); and the role of tide-related vertical mixing on the provision of nutrients to the ice algal communities (with Cota).
