Greenland's ice sheet has an area of 1.7 million square kilometers, an average thickness of 2.3 kilometers (1.4 miles), and holds 7 percent of the world's freshwater. Glaciers on Greenland's coast move ice from the interior of the island to the North Atlantic, where they break off as icebergs and eventually melt into the ocean. Since 2000, Greenland has lost over 4,000 billion tons of ice. If Greenland were to melt completely (which could take thousands of years), global sea level would increase by up to 7 meters (23 feet).