An enormous, virtually level, treeless plain of the arctic regions of Europe, Asia and North America, the tundra is a desert without sand, but with similarly scant precipitation. Two principal kinds exist, arctic and alpine.
The winters are bitterly cold and long. The summer is less than two months. At the extremes, there is constant night in the winter and constant day during the summer.
The northern limits of plant growth occur in the arctic tundra and are confined to matted or shrub vegetation. This area girds the North Pole and reaches south to the taiga.
- Alpine tundra exists on mountains above the treeline.
The ground is permanently frozen; in a word, permafrost. Plant growth and reproduction occur during the brief summer. Low shrubs, sedges, grasses, mosses and lichens constitute plant life. Because of low temperatures, they recover slowly when disturbed. Low temperatures preclude quick decomposition.
There are few animal species on the tundra. Blackflies, deerflies and mosquitoes are prolific during the summer. Plant-eating animals include birds, caribou, musk ox and polar bears.
Arctic peoples are the Eskimos and Inuits.