Earth Observation-based Time Series Analysis of Retrogressive Thaw Slump Dynamics in the Russian High Arctic

• Main Author: Barth, Sophia
• Format: Thesis
• Language: unknown
• Published: Universität Potsdam 2022
• Subjects: Arctic; Canada; Taymyr; Ice; Kolguev; Novaya Zemlya; permafrost; Taymyr Peninsula; Thermokarst
• Online Access: https://epic.awi.de/id/eprint/57279/; https://epic.awi.de/id/eprint/57279/1/Masterthesis_SophiaBarth_29072022.pdf; https://hdl.handle.net/10013/epic.ff2c0999-691d-47b8-9b92-317dad2a90bc; https://hdl.handle.net/

While temperatures are rising globally, they are rising more than twice as fast in the Arctic. Landscapes underlain by permafrost are especially vulnerable to this changing climate and experience increased thaw and degradation. The proceeding warming of organic-rich frozen ground is a highly relevant driver of carbon release into the atmosphere. Retrogressive Thaw Slumps (RTSs) are dynamic thermokarst features which develop when ice-rich permafrost thaws and thus are important indices when it comes to the assessment of potential carbon sources in permafrost landscapes. Thousands of RTSs have been inventoried in northwestern Canada. These inventories showed that thaw slumping modifies terrain morphology and alters the discharge into aquatic systems resulting amongst others in infrastructure instabilities and ecosystem changes. Furthermore, recent studies project that abrupt thermokarst processes contribute significant amounts of greenhouse gas emissions. As observed in most arctic regions, RTS activity has increased in the Russian High Arctic, however, little research has been done on RTSs in this region. The objective of this study is to better understand growth pattern and development rates of RTSs in northern Russia during the last decade. The study area consists of five different 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 deposits or syngenetically formed Yedoma permafrost. To assess changes in number and extent, a GIS based inventory of manually mapped RTSs was created. The inventory is based on multispectral imagery of high-resolution satellite sensors, including PlanetScope, RapidEye, Pléiades and SPOT. Cloud free images were acquired between 2011 and 2020 and exist for each or every few years depending on their availability. Additional data sets such as ArcticDEM, Esri Satellite base map and ...