Wind-forced interannual sea ice and water mass changes on the Ross Sea continental shelf

A simple analytical model of polynya extent is used to parameterize the open-water-fraction along the coast of the Ross Sea. This model was forced by in situ and model-derived wind fields to investigate interannual differences in the wintertime sea ice production and salinization of the water column in the Ross Sea. The study suggests first-order sensitivity to changes in the wind speed and only weak sensitivity to other environmental parameters. The wind fields are highly uncertain and the model is primitive, but they suggest that the entire ice extent in the Ross Sea could be influenced by sea ice produced in the coastal lead along the continent. Wind speeds observed during the Austral winter of 1997 were on average 12% stronger than the winds during the winter of 1996. Hydrographic data collected as part of the Research on Ocean-Atmosphere Variability and Ecosystem Response in the Ross Sea (ROAVERRS) program show an increase in salinity and a decrease in silicate along the along the bottom of the western Ross Sea during Dec-97/Jan-98 relative to the previous year. These changes are small but consistent with increased ice production and salinization of the water column in response to the slightly stronger offshore wind forcing observed during 1997.