Identification and Monitoring of Subglacial Lakes Upstream of David Glacier, East Antarctica, Using ALOS‐2 Differential Interferometry and ICESat‐2 Altimetry

The activity of subglacial lakes in the Antarctic interior can significantly influence downstream hydrology and ice dynamics. Detecting and monitoring these lakes is therefore crucial for understanding ice sheet behaviour. In this article, we applied a differential interferometric synthetic aperture radar (DInSAR) technique to ScanSAR images acquired by the Phased Array type L‐band Synthetic Aperture Radar‐2 onboard the Advanced Land Observing Satellite‐2 between 2015 and 2020 over the upstream region of David Glacier in East Antarctica. Six closed circular fringe patterns were detected from the differential interferograms, one coinciding with the known David 4 lake and five located in previously unreported areas. ICESat‐2 observations from 2019 to 2023 confirmed distinct ice elevation changes within these DInSAR‐detected regions, validating the presence of five new lakes. David 4 drained between 2019 and 2020, then refilled at approximately 0.7 m/yr after mid‐2021. The newly detected lakes exhibited varied behaviours, showing ice surface elevation changes of 0.1–0.5 m/yr. Hydraulic potential analysis indicated strong upstream hydrological connectivity to the newly discovered lakes near David 3 and David 4 , whereas, the two lakes near David 5 show weaker potential flow paths upstream. This article demonstrates the effectiveness of satellite‐based DInSAR for detecting small and slowly evolving subglacial lakes.