• Energy Research

We present a comprehensive inventory of retrogressive thaw slumps (RTS) for six study sites in the Russian High Arctic covering an area of more than 600 km². The sites are located on the Novaya Zemlya Archipelago, Kolguev Island, Bol'shoy Lyakhovsky Island, and Taymyr Peninsula in ice-rich permafrost characterized by either buried glacial ice or syngenetically formed Yedoma permafrost deposits. This data publication contains geospatial polygon vector files of the individual mapped slumps across multiple time slices. The mapping was performed on multispectral imagery of very high-resolution satellite sensors, including PlanetScope (3m ground resolution), RapidEye (5m), Pléiades (0.5m), and SPOT (1.5m). Cloud free images were acquired between 2011 and 2020 and exist for annual or close-to-annual time steps depending on their availability. Additional data sets such as the ArcticDEM, the Esri Satellite base map, and Tasseled Cap Landsat Trends were used to support the mapping process. The identification and digitization of thaw slumps as polygons (in UTM coordinate reference system) was performed in QGIS 10.3. A total number of 3466 individual RTS were mapped between 2011 or 2013 and 2020. In addition, for the coastal slumps, change distances from headwalls and bluff bases were calculated in ArcMap 10.5 using the Digital Shoreline Analysis System (DSAS) tool version 5 over the study period (2011/2013-2020).Very high-resolution imagery for this study was kindly provided by ESA through Third Party Mission proposal TPM4-ID-54054. We recieved access to the RapidEye imagery via the RapidEye Science Archive (RESA) initiative in the scope of our project 'Thaw Dynamics of Retrogressive Thaw Slumps from High Resolution Images in Siberia (RTStrendr )'. The PlanetScope imagery was recieved in the scope of our project ' Artificial Intelligence for Cold Regions (AI-CORE)'. Vector format: ESRI shapefileVector type: polygon, polylineProjection: WGS_1984_UTM, Zones: 54N, 39N, 49N, and 45NParameters: Polygons: attributes: id, area_m², year, image_ids, sensor, sp_res_m, date_, layer, authorPolylines: line_ID, DSAS_date, line_Leng, authorTransects: TransectID, Azimuth, TCD, SHAPE_Leng, NSM, EPR

Field investigations were performed in the central Lena Delta. In total, 25 sites were investigated. The sites were chosen to represent a variety of vegetation communities of the investigated region.30 m2 sample plots (sites) were demarcated in the most homogeneous locations. Heterogeneity was accommodated by roughly assorting vegetation into two to three vegetation types per sampling plot. Within each area of roughly estimated vegetation types we selected one 0.5 x 0.5 m subplot for representative ground-layer above-ground biomass (ABG) harvesting (major taxa and other). For moss and lichen AGB harvesting inside 0.5 x 0.5 m subplots representative 0.1 x 0.1 m subplots were chosen. All ground-layer vegetation AGB assessments were calculated for the fifteen-meter radius plot in g m2 for each sample plot.All harvested AGB samples were weighed fresh in the field. In general, AGB samples with a weight of more than 15 g were subsampled. All samples were oven dried (60 °C, 24 h and weighed again).All data was collected by scientists from Alfred Wegener Institute (AWI), Helmholtz Centre for Polar and Marine Research and University of Potsdam, Germany.