Interactions between Antarctic sea ice and synoptic activity in the circumpolar trough have been investigated using meteorological data from AMPS (Antarctic Mesoscale Prediction System), ECMWF reanalysis, and sea-ice extent and concentration derived from passive microwave data (SSMI/SMMR). In contrast to the Arctic, total Antarctic sea-ice extent does not show large interannual variations. However, large differences are observed on a regional/monthly scale, depending on prevailing winds and currents, thus on the prevailing synoptic weather situations. On the other hand, the sea-ice edge is a preferred region for cyclogenesis due to the strong meridional temperature gradient, meaning high baroclinicity in that area. Motivation for the present study was to try to gain a better understanding of the interaction between sea-ice extent and the general atmospheric flow, in particular the frequency of warm air intrusions into the interior of the Antarctic continent, since this influences precipitation seasonality and has to be taken into account for a correct climatic interpretation of ice cores. A strong influence of sea-ice extent on precipitation seasonality on the continent would allow conclusions on differences between glacial and interglacial times with largely different sea-ice extent, especially in summer. Special interest is given to the seas influencing Dronning Maud Land (including the Weddell Sea), since two deep ice cores have been retrieved there recently. However, the complexity of the problem exacerbates a straight approach. Here we show case studies of extraordinary sea-ice concentration anomalies in relation to the prevailing atmospheric flow. The influence of the Southern Annular Mode (SAM) and possible ENSO teleconnections are discussed.