The Greenland ice sheet is an ice sheet which forms the second largest body of ice in the world. It is an average of 1.67 km (1.0 mi) thick, and over 3 km (1.9 mi) thick at its maximum. It is almost 2,900 kilometres (1,800 mi) long in a north–south direction, with a maximum width of 1,100 kilometres (680 mi) at a latitude of 77°N, near its northern edge. The ice sheet covers 1,710,000 square kilometres (660,000 sq mi), around 80% of the surface of Greenland, or about 12% of the area of the Antarctic ice sheet. The term 'Greenland ice sheet' is often shortened to GIS or GrIS in scientific literature.

Greenland is a North American autonomous territory of the Kingdom of Denmark. It is the larger of two autonomous territories within the Kingdom, the other being the Faroe Islands; the citizens of both territories are full citizens of Denmark. As Greenland is one of the Overseas Countries and Territories of the European Union, citizens of Greenland are European Union citizens. The capital and largest city of Greenland is Nuuk. Greenland lies between the Arctic and Atlantic oceans, east of the Canadian Arctic Archipelago. It is the world's largest island, and is the location of the northernmost area of the world – Kaffeklubben Island off the northern coast is the world's northernmost undisputed point of land, and Cape Morris Jesup on the mainland was thought to be so until the 1960s.