Envisat radar image featuring the northeastern tip of Ellesmere Island (left) in the Canadian Arctic and northwestern Greenland (right) – the world’s largest island. The water (indicated by purple and green colours) pictured in the lower part of the image is Nares Strait. The northernmost part of Nares Strait is the Robeson Channel, which empties into Lincoln Sea (upper left corner of image), part of the Arctic Ocean.