Spatial and Temporal Variations in Antarctic Sea-Ice (1973–82)

Abstract

Monthly estimates of Antarctic sea-ice area for the past decade were extracted from operational churts. Empirical orthogonal function analyses of these satellite-derived data revealed the existence of six distinct ice area sub-regions. Comparison of ice area time series for these sub-regions highlights the substantial differences among them. For example, total sea-ice extent typically reached a maximum in either August or September, while the Ron Sea often exhibited two relative maxima (July and October). The data show considerable year-to-year variability during this short period of record with the minimum sea-ice area varying by more than a factor of two and maximum sea-ice area varying by almost 20%. The large year-to-year variability precludes a reliable identification of longer term trends during the relatively short era of satellite observations.