THE USE OF MICROWAVE REMOTE-SENSING FOR SEA ICE STUDIES IN THE BARENTS SEA

The study of sea ice and ocean processes, using remote sensing data combined with in situ measurements and models, was one of the main objectives of two winter experiments in the Barents Sea, in 1987 and 1989. Remote sensing data were primarily obtained from airborne Synthetic Aperture Radar (SAR), passive microwave and infrared radiometers onboard polar orbiting satellites. The SAR images allowed assessment of several ice characteristics such as distribution of larger and smaller floes, leads, polynyas, convergence zones, and areas of new-frozen ice. Ocean processes observed in SAR images were surface waves, eddies, jets and fronts, all of which have strong influence on the ice conditions. The strong tidal currents in this area (up to 1 m s-1) move the pack ice in tidal ellipses. In high-resolution imagery the tidal ellipses can be seen as tracks in the pack ice produced by grounded icebergs. These images can be used to locate and quantify grounded icebergs. Simultaneously with the experiments a computer based ice model was used to forecast ice drift and ice concentration, with the results transmitted to the ship and compared with field measurements. The remote sensing data available in near real-time were used in the planning and execution of the experiment. Data from new satellites, especially radar satellites are expected to improve substantially the knowledge of sea ice and its interaction with ocean and atmosphere. Remote sensing data from various instruments and platforms will become increasingly important both in research and operational monitoring of sea ice.