Elevation bias due to penetration of spaceborne radar signal on Grosser Aletschgletscher, Switzerland
- 1University of Zurich, Zürich, Switzerland (jacqueline.bannwart@geo.uzh.ch)
- 2Department of Geosciences, University of Oslo, Norway
- 3Remote Sensing Group, Research Unit Land Change Science, Swiss Federal Institute for Forest, Snow and Landscape Research WSL
- 4Remote Sensing Technology Institute, DLR, Oberpfaffenhofen, Germany
- 5Laboratoire d’Etudes en Géophysique et Océanographie Spatiales, Centre National de la Recherche Scientifique (LEGOS – CNRS, UMR5566), Université de Toulouse, France
- 6Department of Geoscience, University of Fribourg, Switzerland
Digital elevation models (DEMs) from the spaceborne interferometric radar mission TanDEM-X hold a large potential for glacier elevation change assessments and monitoring. However, a bias is potentially introduced through the penetration of the X-band signal into snow and firn that can be substantial. The magnitude of this bias has been analysed in some glaciarized regions of the world; still, the knowledge about X-band penetration of TanDEM-X in the European Alps is limited.
In this study, we investigated the unique situation of almost synchronous acquisition of TanDEM-X and Pléiades DEMs over the Grosser Aletschgletscher, complemented with in-situ observations (ground penetrating radar, snow cores, snow pits), all within a four-day period in late winter 2021. The comparison of the TanDEM-X and Pléiades DEM revealed an elevation bias due to radar penetration of up to 8 m above 3400 m. Further, the concurrent in-situ measurements reveal that the signal is not obstructed by the last summer horizon but reaches into perennial firn.
Our study improves our understanding about the magnitude of X-band penetration of TanDEM-X in the Alps and the underlying process with a relevance for glaciology, snow science, remote sensing and the wider geoscience community.
How to cite: Bannwart, J., Piermattei, L., Dussaillant, I., Krieger, L., Floricioiu, D., Berthier, E., Roeoesli, C., Machguth, H., and Zemp, M.: Elevation bias due to penetration of spaceborne radar signal on Grosser Aletschgletscher, Switzerland, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-15661, https://doi.org/10.5194/egusphere-egu23-15661, 2023.
