Short-Term Interactions Between Atmospheric Synoptic Conditions and Sea-Ice Behaviour in the Arctic

Abstract

Passive microwave data (SMMR) and data from drifting buoys are used to examine atmosphere-ice interactions during autumn 1978 through autumn 1982 in the Canada Basin. SMMR brightness temperatures, ratios, and calculated ice concentrations are compared with surface pressure, temperature, buoy motion, and winds at a coincident location to identify possible linkages operating on daily to weekly time-scales. Inter-annual differences in temperature, pressure, and ice conditions inferred from SMMR data are discussed. Periods of reduced ice concentration as estimated by SMMR are found to occur during late summer and early autumn in 1980, 1981, and 1982. The decreases in ice concentration are concurrent with low-pressure systems and increased divergence in the buoy field in 1980 and 1981. These apparent decreases in ice compactness are discussed in relation to previously reported areas of reduced concentration interpreted from ESMR data. Evidence to support a postulated relationship between atmospheric low pressure and divergence of ice under free-drift conditions is demonstrated for the summer of 1980.