It is suggested that the low‐pressure region around Antarctica is associated with a field of negative gravity anomalies. Similar geophysical conditions have been found to prevail in the Greenland region in the Northern Hemisphere, where a thick ice sheet has formed. It is therefore concluded that present geophysical factors are sufficient to explain the paleoclimate of Antarctica and that the Antarctic and Greenland ice sheets could have been formed under atmospheric circulation and climatic conditions similar to those now prevailing on earth.