Permafrost - GCSE Geography Definition

Permafrost is a layer of ground that remains frozen throughout the year. To be considered permafrost, the soil must remain below zero degrees for a minimum of two years. It is found in very cold regions, like the Arctic, Alaska, and Siberia. Permafrost can be just a few centimetres deep or metres thick. During the warm summer months, only the top layer, called the active layer, thaws out, while the rest stays frozen. This frozen ground holds ice, soil, trapped gases like methane and carbon dioxide, and sometimes frozen plants and animals from the past. As the Earth's climate gets warmer, permafrost is beginning to melt, which can lead to changes in the landscape and the trapped greenhouse gases can be released. Understanding permafrost is important because its changes can impact the environment and local communities.