Process of ice-rich permafrost degradation; it taps rapidly into deep permafrost-stored carbon pools and results in the release of organic carbon. This is a rapid process, highly variable and depending on local hydrological, geomorphological, vegetational, climatological, and geological conditions.
Also, thermokarst refers to a landform resulting from ice-rich ground thawing. The melting leaves small, marshy hollows, as the ground settles unevenly. In general, regional thermokarst activity indicates climate change. Along with rising temperatures, an increase of precipitation comes. The melting water of thawing permafrost and the rainwater start pooling in small sinks. WIth warmer water on the surface, compared to the temperature of the underlying ground causes melting of the ice, and the procecess of thermokarst begins.
On the other hand, local forms may be caused by mechanical factors – movement of heavy vehicles or the construction of buildings over permafrost etc.