The Ward Hunt ice shelf
Ice shelves are formed when a freshwater ice cap extends out to sea. In the Arctic, ice shelves are only located along the north coast of Ellesmere Island. The Ward Hunt Ice Shelf is the largest and most important of these shelves. Ice shelves consist of a combination of ice from glaciers and sea ice. Pieces break off the freshwater part of the shelf to form ice islands, the flat icebergs of the Arctic Ocean. A layer of sea ice then freezes to fill the open space left behind. As a result, an ice shelf is actually a patchwork of both sea ice and freshwater ice - a pattern that is actually visible from the air.