Assessing TanDEM-X-Derived Digital Elevation Models for Monitoring Rapid Permafrost Thaw: A Case Study in the Mackenzie River Delta

• Main Authors: Maier, Kathrin, Bernhard, Philipp, Hajnsek, Irena, id_orcid:0 000-0002-0926-3283
• Format: Conference Object
• Language: English
• Published: ETH Zurich, Institute for Environmental Engineering 2023
• Subjects: Permafrost; Retrogressive Thaw Slumps; DEM; info:eu-repo/classification/ddc/550; Earth sciences; Arctic; Mackenzie River; Ice; Mackenzie river; permafrost; Thermokarst
• Online Access: https://hdl.handle.net/20.500.11850/655439; https://doi.org/10.3929/ethz-b-000655439

Permafrost is a common characteristic of Arctic landscapes, where it refers to ground that remains at or below 0 °C for a duration of at least two consecutive years. Permafrost underlies approximately 15 % of the landmass in the Northern Hemisphere and is becoming more susceptible to rapid thawing as the climate continues to warm (Obu et al. 2019). When ice-rich permafrost thaws it can alter the surface characteristics of a landscape which is commonly referred to as thermokarst. Retrogressive Thaw Slumps (RTS) are emerging as one of the most dynamic types of thermokarst, varying strongly in shape and thawing behavior. The prevalence and distribution of rapid thaw on a pan-Arctic scale are not well understood and so is its potential contribution in the Arctic carbon-climate feedback (Kokelj et al. 2009). High-resolution Digital Elevation Models (DEMs) are a valuable tool for monitoring surface characteristics of thermokarst features and track changes over time, which in turn improves our understanding of large-scale landscape changes and their implications for hydrology, biochemistry, permafrost stability, and hazard risk management (Jorgensson and Grosse 2016). To derive these DEMs, a range of techniques are employed, including ground-based and aerial LiDAR (e.g., Patton et al. 2021), optical stereo-imagery from airborne (e.g., Lim et al. 2020) and satellite platforms (e.g., Günther et al. 2015). The high-resolution ArcticDEM has been used to supplement optical satellite data in monitoring highly dynamic thermokarst features such as RTS towards the pan-Arctic scale (Yang et al. 2023). However, these methods are subject to spatial coverage and availability constraints, or data quality issues and data gaps due to limitations such as cloud cover, seasonal snow, vegetation, and illumination conditions for passive optical sensors. Another high-resolution DEM covering the Arctic landscape has been available with the start of the TanDEM-X satellite in 2010, forming together with the TerraSAR-X satellite the TanDEM-X ...