ИСТИНА

The Yamal-Gydan geographical region of the north of West Siberia is one of the most industrialized parts of the Russian Arctic. Rich gas and oil reservoirs induce rapid growth of infrastructure pressure on natural landscapes. Along with climate warming in the Arctic, infrastructure causes excessive increase in drained lake basins (DLBs) and retrogressive thaw slumps (RTSs). Activation of these processes in their turn can damage existing infrastructure. Both phenomena can undergo cycles. Lake drainage can be followed by refilling and repeated drainage if connected to floodplains and RTSs can activate and reactivate periodically. These cycles of plant recovery within active surfaces and their impact can be analyzed with very high-resolution satellite imagery time series. Two key sites have been investigated, central parts of Yamal and Gydan peninsulas covering areas of 200 and 60 sq. km, respectively, to track changes and formation of RTS for a period from 2009 to 2019. All RTSs were split into different categories, based on their status in 2010, 2013 and 2018 for the Yamal peninsula and 2009, 2013 and 2019 for the Gydan peninsula. In the next step, Sentinel-2 satellite imagery was used to identify lake drainage events near these areas between 2016 and 2022. Statistical analysis of all the RTS’s categories and selected DLB’s was done using the land surface classification developed for ESA DUE Globpermafrost and Permafrost_cci projects based on combination of unsupervised and supervised classifications of Sentinel-1 and Sentinel-2 satellite imagery. The results of the analysis allow us to identify similarities and differences in succession of vegetation for DLBs and RTSs in this macro-region.