Coastal dynamics of the Kolguev Island

• Main Authors: Kizyakov, Alexander I., Günther, Frank, Zimin, Mikhail V., Sonyushkin, Anton V.
• Format: Conference Object
• Language: unknown
• Published: Russian Academy of Science Institute of Physicochemical and Biological Problems in Soil Science RAS "Okabiolab" Ltd. 2019
• Subjects: Barents Sea; Kolguev; Sea ice
• Online Access: https://epic.awi.de/id/eprint/51214/; http://cryosol.ru/images/phocagallery/conference/cryospherepuzzles/PushchinoPermafrost_ConferenceProgrammAbstracts2019_compressed.pdf; https://hdl.handle.net/10013/epic.4e40b193-1088-417b-8846-2f922a23ed0f

Kolguev Island is the most western point in the Russian Arctic with tabular ground ice occurrence. Since the Barents Sea is characterized by strong sea ice decline, it is very interesting to study coastal dynamics in conjunction with cryogenic processes in this region. Ice exposures on coastal bluffs favor the activation of thermal abrasion and thermal denudation. Headwall retreat of retrogressive thaw slumps causes not only thermocirque formation, but also leads to increasing coastal destruction rates. This study on Kolguev Island continues and expands our earlier research efforts on coastal dynamics in the region. As a result of field and remote sensing data analysis, coastline classification and segmentation were done according to the morphodynamics principle. The following types are defined: 1) thermo-abrasion wave exposed cliffs, 2) abrasion (thermo-abrasion) with stabilized cliffs, bordered by beaches or accumulative terraces, 3) sheltered abrasion (thermo-abrasion) cliffs, 4) accumulating coasts and accumulative forms, 5) accumulated coasts with sheltered tidal flats, 6) deltas. Thermo-abrasion cliff coasts are predominantly distributed in the west, north and northeast of the island, and accumulative shores in the south, southeast and east of the island. New data on thermal denudation and thermal abrasion rates for Kolguev Island have been obtained using a whole set of multi-temporal satellite images of high and very-high spatial resolution (GeoEye, WorldView, Alos Prism, SPOT, Formosat, RapidEye and Kompsat) covering the period from 2002 to 2017. For image orthorectification purposes, the 12 m TanDEM-X DEM has been used. However, since the TanDEM-X DEM is based on averaged bistatic SAR surveys acquired during the period 2010–2012. This DEM can be used only for orthorectification of images newer than 2012 to determine the exact coastal bluff position and thermocirque edges. We therefore reconstructed the relief along erosive coastline segments by modifying the initial TanDEM-X DEM through extrapolation of ...