Arctic Polar Desert - Code: Ne10A

The northernmost vegetated area is one of both bitter cold and aridity (Koppen ET). The polar desert receives less than 10 in. (250mm) of precipitation per year and never has a month when temperatures average over 50°F (10°C). What truly separates this climate regime from others is not the bitter winters, because the tundra to the south also has those, but rather but the cold summers. The ice may melt for a very short period of summer, allowing photosynthesis to start at about 36°F (2°C), but there is no prolonged period of growth before temperatures drop to 23°F (⎻5°C) and photosynthesis halts, so plant life is severely limited to the hardiest of species. The ground is sparsely covered, with no closed vegetation cover, and over 90% of the surface is bare rock. Plants exist in protected areas in cracks and hollows and consist mainly of crustose (flat-laying) lichens such as , though some freestanding (fruticose) lichens such as Stereocaulon rivulorum survive in the most protected areas. Mosses, and very rarely forbes such as  Regel's chickweed (Cerastium regelii), pygmy saxifrage (Saxifraga hyperborea), and  purple saxifrage (Saxifraga oppositifolia),  and gramanoids (grasses and similar plants) such Ice Grass (Phippsia algida),  Adam's Whitlow-grass (Draba pauciflora), Northern Wood Rush (Luzula confusa), occur only where fine soils and moisture have accumulated in the best-protected areas.

Because of the low temperatures and lack of water, there is almost no chemical weathering of the rocks here, and most of the disintegration of rock material is through frost and wind abrasion; few nutrients are available to sustain growth, and there is rarely a relationship between flora and underlaying rocktype. Nutrients are derived either by the rotting of existing flora or the occasional input from defecation or rotting of seabirds and the occasional mammal such as walrus or Polar Bears.