The Arctic tundra, is in the far Northern hemisphere, encompassing parts of North America, Greenland, and Eurasia and has a latitude and longitude of 71.2 degrees N and 156 degrees W. Features include permafrost where the soil is permanently frozen as well as a lack of trees due to the frozen soil. Bare rocks can support lichens and moss and certain varieties of berry. Winter and summer are the two seasons, and winter is cold and dark. In summer, the top layer of permafrost melts allowing for a soggy soil and a brief growing season. The tundra has low biodiversity, as only very adapted plants and animals can exist in these extreme conditions.