Thermokarst refers to the land surface that forms as ice-rich permafrost thaws and collapses, creating features like sinkholes, ponds, and uneven terrain. This process is significant in periglacial geomorphology for understanding the impacts of climate change on permafrost regions and the associated risks of land subsidence.
Reference: French, H. M. (2007). “The Periglacial Environment.” John Wiley & Sons.