Permafrost

Similar term(s): pergelisol.

A layer of soil or bedrock at a variable depth beneath the surface of the earth in which the temperature has been below freezing continuously from a few to several thousands of years.

While the top layer of soil heats up in the summer, permafrost exists in deeper layers where the summer heating fails to melt the frozen ground. A continuous layer of permafrost is found in areas where the annual mean temperature is below about −5°C (23°F).

Source: based on AMS Glossary of Meteorology  

GreenFacts Summary on Climate Change 2007 Update:

• 1. What makes the climate change?

Español: Permafrost
Français: Permafrost

Climate Change

Arctic Climate Change

Climate Change

Climate Change

Soils degradation