arctic

Often, soils from cold regions, such as Arctic soils, show polygonal forms in their surface. These polygons are formed because of the freeze-thaw cycle, characteristic of permafrost. What is permafrost? Permafrost is a subsurface soil layer which stays permanently frozen (below 0 oC) during long periods of time, usually more than two consecutive years. Most extensive permafrost areas can be found ...[Read More]