Electromagnetic and physical properties of sea ice formed in the presence of wave action

Abstract

Estimating the magnitude of brine flux to the upper ocean requires an ability to assess the dynamics of the formation of sea ice in a region. Brine storage and rate of expulsion is determined by the environmental conditions under which the sea ice forms. In this paper, the physical and electromagnetic properties of sea ice, formed under wave-agitated conditions, are studied and compared with results obtained from ice formed under quiescent conditions. Wave agitation is known to have a profound effect on the air-ice interface and internal ice structure. A variety of sensors, both active and passive, optical and microwave, were used to perform this characterization. Measured electromagnetic parameters included radar backscatter, microwave emission, and spectral albedo in the visible and infrared. Measured physical properties included ice structure, brine and temperature distribution, profiles of the vertical height of the air-ice interface, and ice formation processes. Results showed that emission, backscatter, and albedo all take different signature paths during the transformation from saline water to young sea ice and that the paths depend on sea surface state during ice formation.