Evidence of Cascading Subglacial Water Flow at Jutulstraumen Glacier (Antarctica) Derived From Sentinel-1 and ICESat-2 Measurements

• Published in: Geophysical Research Letters
• Main Authors: Neckel, Niklas, Franke, Steven, Helm, Veit, Drews, Reinhard, Jansen, Daniela
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Wiley 2021
• Subjects: Antarc*; Antarctic; Antarctica; Jutulstraumen Glacier
• Online Access: https://epic.awi.de/id/eprint/54791/; https://epic.awi.de/id/eprint/54791/1/2021_Neckel_GL094472.pdf; https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021GL094472; https://hdl.handle.net/10013/epic.d0356403-3a8d-4060-b578-0528b076f59a

Migration of subglacial water underneath thick Antarctic ice is difficult to observe directly but is known to influence ice flow dynamics. Here, we analyze a 6-year time series of displacement maps from differential Sentinel-1 SAR interferometry (DInSAR) in the upstream region of Jutulstraumen Glacier. Our results reveal short-term (between 12 days and 1 year) interconnected subsidence- and uplift events of the ice surface, which we interpret as a pressure response to the drainage and filling of subglacial lakes. This indicates an episodic cascade-like water transport with longer quiescent phases in a dynamically stable glacial setting. Abrupt events appear in the DInSAR time series and are confirmed by ICESat-2 altimetry. The events can be traced for a 1-year period along a urn:x-wiley:00948276:media:grl63164:grl63164-math-0001175 km flow path. We are able to observe the migration of subglacial water with unprecedented spatial and temporal resolution, providing a new observational baseline to further develop subglacial hydrological models.