Greenland, the largest island in the world, is located at the point where the Atlantic meets the Arctic Ocean. It is surrounded by cold ocean currents which continually cool its coasts. Combined with cold radiating from inland ice, this gives Greenland its arctic climate. The inland ice covers 1,833,900 square km, equivalent to 85 percent of Greenland's total area. At its center, it can be up to 3 km thick. This large concentration of ice represents 10 percent of the world's total fresh water reserves.