Abstract
During the post-war period the pressure field at Greenland has been characterized by long-sustained winter regimes of alternating high and low pressure, with important effects on the winter climate of Europe. Although these alternations of pressure anomaly at Greenland may be shown to be associated with periods when the pattern of long waves in the upper westerlies showed a general reversal over much of the Northern Hemisphere, it is also suggested that within this hemispheric pattern of change, contemporary variations of winter climate along the Atlantic seaboard of North America have exerted an important influence on the pressure field at Greenland and, through teleconnections, elsewhere (e.g., the North Atlantic and Europe). Comparing months of extreme winter warmth and cold over the southeastern United States it is shown that changes in the strength of the baroclinic field at the coast are associated with major changes in the distribution of winter storms. More specifically, during winters of extreme cold over the southeastern United States and the associated enhanced baroclinicity at the Atlantic seaboard, the zone of peak winter storm frequency is drawn far to the southwest of normal, with a corresponding decrease in cyclonic activity in the Iceland-Greenland area.