Sea-ice properties off Labrador and Newfoundland during LIMEX '89

During the cold winter of 1988/89, ice coverage was abnormally high over the Newfoundland Shelf, but was low over the northern Labrador Shelf. The pack-ice aligned in bands parallel to the coast and bathymetry, with thin ice and open water occurring inshore of the thick pack-ice, a result of ice divergence along the coast and the large ice-melt rates at the shelf break. Freezing degree-day models predicted higher than normal ice thicknesses at land-fast ice stations when climatic mean snow-layer depths were used. However, observed ice thicknesses were below normal, which could only be predicted when observed snow conditions were used. Offshore winds generated ice divergence, which stimulated increased ice growth in the nearshore region, which in turn caused the large surface mixed layer depths and high salinity values. Ice drift rates obtained from satellite-tracked ice beacons had two-week averaged speeds of 18 km d −1 equal to the large horizontal melt rates of the ice edge over the shelf break bordering the Labrador Sea. Ice drift rates of up to 75 km d −1 were observed during strong northwesterly winds over the continental slope where the Labrador Current is located.