A polar stereographic plot of the Arctic regions. The North Pole is at the centre and the lowest latitude is 50° N. There are concentric lines of latitude at 60° N, 70° N and 80° N. The Arctic Circle (66.6° N) is shown as a dashed line. The oceans are coloured blue. The land is coloured according to one of five categories. With the exception of northern Scandinavia, all land within the Arctic Circle, including most of northern Russia, part of Alaska, northern Canada and the coast of Greenland, is coloured dark purple which represents continuous permafrost. Within Russia and northern Canada, continuous permafrost extends further south to below 60° N. South of these regions (with the exception of the non-coastal areas of Greenland which are covered by an ice cap) is a lighter pink region which represents discontinuous permafrost. Further south of this region and in most of Scandinavia is a yellow colour which represents sporadic permafrost. Finally there is a green region which represents isolated permafrost. Part of Iceland is shown as experiencing isolated permafrost.