PermaSAR: SAR detection of permafrost landscape changes in northern Norway and on Svalbard

One of the main tasks of the Research Project PermaSAR are using satellite radar interferometry (InSAR) to produce maps showing the movement of the ground in areas of permafrost, and to characterize the seasonal freezing and thawing processes. One of the most common landforms in areas of permafrost are solifluction, where the soil slowly moves down the slope due to freezing and thawing processes. In August 2013 Norut installed a station to monitor solifluction on Nordnesfjellet. The station will provide unique information about the movements in the soil, both horizontally and vertically. Many of the most unstable mountain areas known to date are located in areas with sporadic or continuous permafrost. The presence of permafrost is documented as a controlling and driving factor for movement speed by unstable hillsides Blikra and Christiansen (2012). Their findings show that in deep cracks may develop local permafrost. In August 2014 Norut installed temperature loggers and cameras to monitor the fracture systems in the unstable mountain areas Gamajunni 3 Manndalen and Ádjit east of Skibotn. It was placed out 4 cameras that monitor fracture systems within the unstable mountain areas. We want to see how temperature affected the cracks in terms of whether they are covered in snow or not and whether this controls the speed of movement. The Sentinel-1a radar satellite, which is a part of the European Copernicus program, was launched in 2014. This satellite will provide new unique opportunities for large-scale mapping and monitoring of processes related to permafrost. The results achieved in the PermaSAR project will form an important basis for further operationalisation through the Sentinel satellites.

Many potential environmental and socioeconomic impacts of global climatic change are associated with permafrost. The effects of climatic change on permafrost, and the seasonally thawed layer, can severely disrupt ecosystems and human infrastructure and po tentially intensify global warming. Permafrost degradation may affect slope stability, and in order to evaluate certain geohazards, improved permafrost knowledge is essential. The scientific objective is to increase the understanding of climate change ef fects on permafrost landscapes through satellite interferometric SAR (InSAR) information retrieval studies in combination with high-resolution field studies of selected widespread permafrost landforms. The technical objective is to develop and validate ad vanced information retrieval approaches for temporal analysis of high-resolution satellite InSAR data from the Radarsat-2 (Ultrafine mode) and TerraSAR-X sensors. Geographically the research will be done in the arctic parts of northern Norway and Svalbar d, where we can study both comprehensive continuous permafrost landscapes with a large diversity of permafrost landforms (Svalbard) and of sporadic permafrost occurring in the special character topography of large unstable rock slopes (northern Norway). T his combination is then largely covering all types of terrestrial permafrost on Earth. Ground based field measurements will be used to validate the InSAR data, and we aim to use the InSAR displacement data to upscale the in-situ point measurements from t he existing permafrost research infrastructure on Svalbard. The project will collaborate with the University of Fairbanks permafrost remote sensing group and the Radar interferometry group at Stanford University.