Supraglacial lake drainage through gullies and fractures
- 1Alfred-Wegener-Institut Helmholtz Zentrum für Polar-und Meeresforschung, Glaciology, Bremerhaven, Germany (angelika.humbert@awi.de)
- 2University of Bremen, Department of Geosciences, Bremen, Germany
- 3CNR-IIA Institute of Atmospheric Pollution Research, National Research Council of Italy, Italy
- 4FAU Erlangen-Nürnberg, for Geography, Erlangen, Germany
- 5University of Stuttgart, Institute of Applied Mechanics, Stuttgart, Germany
- 6Technical University of Darmstadt, Institute for Mechanics, Division of Continuum Mechanics, Darmstadt, Germany
- 7Bavarian Academy of Science and Humanity, Section Glaciology, Munich, Germany
The mechanisms of drainage of supraglacial lakes are not yet fully understood. Here we present an indepth study of drainage characteristics of a 21km^2 large supraglacial lake in Northeast Greenland from its genesis in mid 1990s to 2023. We discuss the fracture modes involved in drainage and compare this to simulated principal stress fields. A particular focus of the presentation is the formation of gullies. Using high resolution optical satellite imagery (WV2 and Planet), we detect fracture networks at the surface. We find evidence for reactivation of former gullies in subsequent lake drainage events. In addition we present viscoelastic modelling of gullies at the surface that support the continued existence of open gullies at the surface. In vertical direction, we surveyed the glacier using airborne radio echo sounding in 2016, 2018 and 2021. This data reveals englacial channels and their remnants over the entire live span of the lake.
How to cite: Humbert, A., Helm, V., Zeising, O., Neckel, N., Salzano, R., Esposito, G., Braun, M., Steeb, H., Sohn, J., Bohnen, M., Müller, R., and Rückamp, M.: Supraglacial lake drainage through gullies and fractures, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16416, https://doi.org/10.5194/egusphere-egu24-16416, 2024.
