A Landsat based monitoring framework for permafrost landscape dynamics

• Main Authors: Nitze, Ingmar, Grosse, Guido, Jones, Benjamin M., Hayes, Daniel J.
• Format: Conference Object
• Language: unknown
• Published: 2016
• Subjects: Climate change; Ice; permafrost; Thermokarst; Tundra; wedge*
• Online Access: https://epic.awi.de/id/eprint/41185/; https://hdl.handle.net/10013/epic.48125

Recent and projected future climate warming strongly affects permafrost stability over large parts of the terrestrial Arctic with local, regional and global scale consequences. The monitoring and quantification of permafrost and associated land surface changes in these areas is crucial for the analysis of hydrological and biogeochemical cycles as well as vegetation and ecosystem dynamics. It is also necessary for improved understanding of the consequences of climate change on past and present permafrost stability and potential future landscape conditions. Changes within vulnerable permafrost landscapes occur on different spatial and temporal scales and can result from both press (gradual) and pulse (event-driven) disturbances. Press disturbances that result from top down permafrost thaw have the potential to impact large expanses of the Arctic that will in turn change vegetation communities and hydrological conditions. Furthermore, destabilization of coastal regions has been identified as critical for the carbon cycle, but also for many Arctic communities built on permafrost terrain. Rapid thaw processes associated with land surface subsidence (thermokarst) and erosion in regions underlain by ice rich permafrost are a strong indicator of permafrost degradation. Typical thermokarst-related press disturbances include thaw slumps, detachment slides, degrading ice wedges, and thermokarst lake dynamics. Various stages of the thermokarst lake cycle that include thaw subsidence, ponding, lake formation, -expansion, and -drainage as well as vegetation succession affect vast stretches of coastal lowlands. In recent years, tundra fires have been recognized as an important disturbance which may trigger widespread permafrost degradation in severely burned areas. Due to the size and remoteness of the Arctic, a large portion of potentially ecosystem-critical disturbance processes and landscape shifts remain undetected. Remote sensing methods are therefore important for understanding and quantifying these landscape dynamics. ...