Description and general info:

Tundra: from Finnish word tunturi which means treeless plain

Also known as polar grasslands

Coldest and driest of all biomes

In northern and southern most latitudes

Areas such as North Europe, Siberia, Northern most part of North America, a few plains in the southern hemisphere (area has more ocean than land)

Simple vegetation structure

            -Low shrubs, sedges, reindeer mosses, liverworts, grasses

            -lichen- on rocks, close together

            -grow close to the ground to protect from cold

Climate

Average temperature is less than 5 degrees Celsius. The coldest weather of the tundra occurs in northeastern Siberia. Although the winter months are so cold, the tundra has mild summers with an average temperature of 45 degrees F. Alaska, Canada, and Siberia have the warmest summers out of the Tundra region.  

Precipitation-usually snow-less than 100 mm per year. During the summer, when it is not snowing, the Tundra is usually very foggy. Although there is little rain and snow, the land is wet because of how long it takes the water in the tundra to evaporate and because of poor drainage.

Biomass and Productivity

   Biomass: mass of living biological organisms in a given ecosystem at a given time

Net primary productivity by (kilocalories/ square meter/ year): 600

Approx. kilocalories per square meter per day: 2

Rainfall per year in inches: less than 10

Type of land: barren- ice, sand, tundra desert

% of earths land surface: 33%

Threats

Airborne pollutants such as DDT and PCB’s

Oil and gas development causing global warming

Drilling for oil

Animal

The polar bear is one of the animals living in the tundra. It has clear fur that appears white when hit by the light. The largest carnivore, its shoulder height can be over five feet, and when standing the polar bear can reach heights from eight to eleven feet. Females can weigh anywhere from 660-770 pounds, while the males can weigh from 880-990 pounds. It mainly preys on seals, but also eats other sea life, and whale and walrus carcasses.  In the summer polar bears will eat lemmings, arctic foxes, ducks, and occasionally some plants.

The polar bear, whose scientific name means “sea bear,” is properly named. It has a longer neck than other bears to help it keep its head above water. They have strong legs and webbed feet to help them swim.

The polar bear is able to handle the cold due to its two layers of fur, which is hollow and creates insulation. Underneath this is black skin that absorbs heat. Also, they have short ears and tails so that little heat is lost. It also has around 4.5 inch thick blubber to help keep warm.

The polar bear is not currently endangered, but chemicals polluting their food stock and melting ice packs poses a threat to them.