Outline the relationship between climate and one or more biomes. (10 marks)

Outline the relationship between climate and one or more biomes.

Arctic tundra is a biome characterized by cold weather and low growing plants and shrubs and virtually no trees. They are found mainly in regions just below the Arctic ice caps, located at latitudes 55o to 70o North, across North America, Europe, Alaska, Canada and Siberia. They cover 20% of the earth’s surface. The summer season is short, where there are brief periods when the sun shines for almost 24 hours a day and temperatures never go above 45o or 50o F. In winter, temperatures don’t reach above 20o F and average between -20o to -30o F. Tundra biomes receive low levels of precipitation, around 150 to 250 mm of rain per year. Due to the harsh climate, vegetation such as low shrubs, sedges and reindeer mosses have adapted by growing close to the ground and close together, as this helps plants to resist the effects of cold weather and reduce damage caused by snow and ice. Plants are also small and roots are shallow to skim the thin unfrozen layer on top of the permafrost (a thick layer of soil that remains frozen throughout the year. Permafrost is also the reason why there are virtually no trees in tundra biomes, as not enough moisture can percolate the soil). However, in the summer months the top part of the soil partially thaws, forming bogs and ponds, allowing some vegetation to grow.

Animals such as insects, bears and arctic foxes, have adapted to living in the tundra. For example, since food is scarce in the winter, bears have adapted their diets and will dig up roots or even eat seaweed found along water sides in order to avoid starvation. The arctic fox has also adapted to surviving the climate, such as having thick fur and a good supply of body fat to help keep it warm. The arctic fox also has a low surface area to volume ratio, which means less of its surface area is exposed to the arctic cold and less heat escapes the body.