Tundra

Tundra Location and Climate

The tundra is found across northern Alaska, Canada, and Siberia. It is the coldest of all the biomes. This biome has long cold winters and short cool summers. The temperatures range from -40°C to 18°C. The tundra has low precipitation (15-20 cm) per year and dry winds. These conditions make the Arctic tundra a desert-like climate. The growing season is short (50 to 60 days). Soil is slow to form and is nutrient poor.

PermafrostOne unique characteristic of the tundra is permafrost--ground that is permanently frozen. The surface layer above the permafrost thaws each summer. During the summer the Arctic tundra has lots of surface water. When snow melts, the water is unable to penetrate the permafrost. Since the water has nowhere to go, pools of water form on the surface.

Land of the Midnight SunAnother characteristic of the tundra is the limited amount of sunlight it receives due to the position of the Sun in the sky. The Sun can remain below the horizon for up to 2 months in the winter, leaving the region in total darkness. Although the sun remains in the sky 24 hours a day during the summer, it stays close to the horizon and provides only low intensity sunlight.

Tundra AnimalsMammals

(Carnivores) Polar Bears Gray Wolves Artic Fox Seals Walrus Ermine

Tundra Animals (Carnivores)

Artic Fox

Harp Seal Pup

Artic Fox Pups

Polar

Bear

ErmineWalrus

Tundra AnimalsMammals

(Herbivores) Caribou Musk Ox Lemmings Snowshoe Hares Ground Squirrels

Caribou

Musk Ox

Tundra Animals (Herbivores)

Tundra Animals (Herbivores)

Lemming

Snowshoe Hare

Ground Squirre

l

Tundra Birds Snowy Owl Ptarmigan Red Phalarope Puffin King Eider Snow Geese

TUNDRA BIRDS

Snowy Owl Tundr

a Swan

Puffin

Snow Goose

Ptarmigan

King Eider

Arctic Tern

Red Phalarope

Adaptations in Tundra Animals

Not many kinds of animals live year-round in the tundra. Most birds and mammals only use the tundra as a summer home. Animals that live year round in the tundra need to find ways to stay warm and to provide nourishment for themselves in order to survive the long, cold, winter months. Migration and hibernation are examples of behavioral adaptations used by animals in the tundra

Hibernation is a combination of behavioral and physical adaptations. Some animals like bears are able to store the food eaten during the summer as a layer of fat underneath their skin. The layer of fat insulates the animal from the cold. While in hibernation the fat is slowly converted into energy to maintain life.

A structural adaptation used by the Musk Ox is the growth of two layers of fur--one short and the other long. Air is trapped in the short layer of fur and is warmed by body heat. The warmed air, trapped close to the body, acts as insulation from the cold. The layer of long fur protects the Musk Ox from the wind and water. In addition to thick layers of fur, the Musk Ox relies on another structural adaptation to help it survive. The hooves of the Musk Ox are large and hard. During the winter months, this adaptation allows the Musk Ox to break the ice and drink the water underneath.

Tundra PlantsOnly plants with shallow root systems grow in the tundra because the permafrost prevents plants from sending their roots down past the surface layer of soil. The surface layer of soil is free from ice for only 50 to 90 days. Common tundra plants include:

Mosses Lichens Low-growing shrubs Grasses and Sedges

Lichen

Cushion Plants

Cotton Grass Purple Saxifrage

TUNDRA PLANTS

Reindeer Lichen

Willow

More Tundra Plants

Plant Adaptations Plants need warmth and sunlight to grow and reproduce. In the tundra, warmth and sunlight are in short supply, even in the summer. The ground is frequently covered with snow until June, and the Sun is always low in the sky. Plants have adapted to the tundra by developing the ability to carry out photosynthesis in extremely cold temperatures, and for flowering plants, to produce flowers quickly once summer begins.

Growing close together and low to the ground are some of the adaptations that plants use to survive. This growing pattern helps the plant resist the effects of cold temperatures and reduce the damage caused by the impact of tiny particles of ice and snow that are driven by the dry winds.A small leaf structure is another structural adaptation that helps plants survive. Plants lose water through their leaf surface. By producing small leaves the plant is more able to retain the moisture it has stored.

Tundra Landscapes