A study is presented of the seasonal and interannual variability of Arctic sea#x2010;ice extent over the 32#x2010;year period 1953#x2013;84. The data set used consists of monthly sea#x2010;ice concentration values given on a 1#xB0;#x2010;latitude grid and represents a 7#x2010;year extension of the 25#x2010;year data set analysed by Walsh and Johnson (1979). By focussing attention on the variability in seven distinct subregions that circumscribe the polar region, a number of interesting spatial patterns emerge in the regional seasonal cycles and anomalies of ice coverage. For example, the time#x2010;scale of the smoothed anomaly fluctuations varies from a 4#x2013;6 year cycle in the western Arctic (e.g. the Beaufort Sea) to a decadal one in the eastern Arctic (e.g. the Barents Sea). Also, in agreement with earlier studies, a significant out#x2010;of#x2010;phase relationship was found between the 25#x2010;month smoothed anomalies in the Beaufort and Chukchi Sea region and the Greenland Sea. It is proposed that this behaviour is related to atmospheric pressure anomalies associated with the see#x2010;saw in winter air temperature between northern Europe and western Greenland. Finally, a particularly large 9#x2010;year ice anomaly in the Greenland Sea that was centred on 1968 appears to have evolved into a substantial 4#x2010;year Labrador Sea anomaly that peaked in 1972. Both of these anomalies coincided with the passage of the #x201C; Great Salinity Anomaly#x201D;, which traversed cyclonically around the subpolar gyre in the northern North Atlantic during the period 1968#x2013;82.
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