The Antarctic Continental glacier is estimated to have a thickness of about 4000 meters and an area of about 8 million km2. The surface of the glacier which is about seven times as extensive as the Greenland ice-sheet, rises in the form of a plateau about 4300 meters above sea level. This huge glacial sheet covers most of the continent except a few coastal areas and mountains occurring in the marginal zones. The ice sheet is not confined to the continent but extends into the sea as huge shelf sometimes 400 meters thick, e.g. Ross Ice Shelf whose edge forms ice cliff 30 to 50 meters high. The ice margin remains more or less static because the loss in the form of breaking ice-bergs or otherwise is made good by the advance of continental glacier towards the margin. The ice mass beyond the shore floats, i.e., is raised and lowered respectively with the flow and ebb of tide.
The Greenland continental glacier extends over about 1,300,000 km2 covering some three-fourths of the island, the thickness of the ice being about 3000 meters in the middle of the dome. Towards the margins rock masses of the mountains and ridges rise above the ice mass as what are known as ‘nunataks’.
Among the present day ice caps or smaller ice masses are those of Iceland, Spitzbergen and arctic islands north of Canada.