Tundra is the coldest climate on the planet. The average summer temperature is 37 to 54 degrees Fahrenheit; the average winter temperature is negative 30 degrees Fahrenheit. These temperatures limit the growing season to a mere 60 days a year. The weather also stifles drainage, which causes shallow pools of water to sit on the surface. Severe winds rage through the region.
The topmost ground level is a shallow layer of life-sustaining soil. It is thin by comparison to the soil depths of other biomes. The layer of earth beneath the surface soil is permanently frozen soil called permafrost. Dense rock forms are below the permafrost. Though the area is mountainous, it is not characterized by the high peaks that highlight other mountainous regions. Tundra mountains are elevated, but flat.
Tundra is the climate region of the northernmost land on the planet. In North America, northern Canada and the majority of Alaska are tundra. A thin band across the top of Scandinavian Europe, Russia, and mainland Asia is tundra, as well. Tundra does not exist in the Southern Hemisphere.
Though a limited amount of biolife exists in the tundra biome, that is not to say it is devoid of life altogether. Approximately 1700 species of organisms live in this climate. Plant life is limited to species with short root systems. Since the life-sustaining soil is shallow, it does not allow for deep, extensive root systems. Since plants cannot draw water and nutrients from deep within the soil, surviving plants must be able to live on few nutrients that are easy to acquire from the surface. Subsequently, the majority of the biome's nutrient content comes from dead material on the surface. Animal life consists of mammals that can hibernate for extensive periods of time, like polar bears and caribou.