The Antarctic ice cap
Over the past decade, it has been observed that the glaciers of the Antarctic Peninsula are moving more quickly, and several ice shelves have broken up. Ice shelves act rather like dams, holding back the glaciers farther inland, and scientists suspect that if the shelves disappear, large sectors of the inland ice sheet could be affected.
Antarctica receives so little precipitation it is to all intents and purposes a desert. Up on the ice plateau it snows no more than a few centimetres per year.
But the little snow that falls is compressed into ice that moves slowly toward the coasts. When it reaches the sea, the ice sheet floats on the water and forms an ice shelf, like Fimbulisen north of the Norwegian research station Troll. Ice shelves calve at the seaward edge, and large or small icebergs break off.