Remote Sensing for Identification and Mapping of Thermokarst Landforms: A Review

Permafrost is deeply involved in a series of geophysical processes, and it plays an important role in the hydrology cycle, vegetation evolution, and greenhouse gas emission. As one of the most sensitive indicators of global climate warming, the dynamic changes in permafrost distribution and its thermal state have been the focus of cryospheric change research. The highly developed remote sensing technology can provide abundant earth observation data over a wide spatiotemporal range, and it has become a powerful approach to detecting permafrost variations and their related landforms. In this review, we summarize the applications of remote sensing technologies in identifying and mapping typical thermokarst landforms that are closely related to permafrost degradation, namely, thermokarst lakes, thaw slumps, and thermokarst bogs. We emphasize the great potential of using automated methods on high‐resolution optical images and the extraction of multi‐temporal kinematic information from laser scanning and interferometric synthetic aperture radar (InSAR). We not only show the usefulness of remote sensing in the identification and mapping of thermokarst landforms, but we also point out several limitations and future directions for further improvement.