Characteristics of cold environments

what % of the earth's land area do cold environments cover

25%

cold environment climate

high latitude where cold, sinking air generate winds, low sunlight

polar regions

permanently frozen ice caps with extreme cold and no soil

tundra regions

slightly warmer with an 'active' surface layer of soil that thaws in the summer, supporting low lying vegetation

cold environment interdependence

mammals and birds line their nests with moss, inuit people use animals, low lying plants protect soil from erosion

active layer of soil, cold environments

up to 25cm, frozen in winter, thawed in summer

permafrost

has remained frozen for at least 2 years, usually 25

talik

unfrozen ground beneath permafrost, can establish root growth

what % of the northern hemisphere has permafrost

almost 25%

what is permafrost made of

sand, soil and stones, held together by ice

continuous permafrost

a continuous sheet of frozen material, extends under all surfaces except large bodies of water

discontinuous permafrost

permafrost broken up into separate areas

what happens when permafrost melts

sea levels rise and soil will be eroded