| Term: | Permafrost aggradation |
| Definition: | A naturally or artificially caused increase in the thickness and/or areal extent of Permafrost. Permafrost Aggradation may be caused by climatic cooling or by changes in terrain conditions, including vegetation succession, infilling of lake basins in areas underlain by Permafrost, drainage of lake in Permafrost terrain and a decrease in Snow Cover and thus the insulating agent. It may be expressed as a thinning of the Active Layer and/or a thickening of the Permafrost. |