Mapping the grounding line of Antarctica in SAR interferograms with machine learning techniques

• Main Authors: Ramanath Tarekere, Sindhu, Krieger, Lukas, Heidler, Konrad, Floricioiu, Dana
• Format: Conference Object
• Language: English
• Published: 2022
• Subjects: SAR-Signalverarbeitung; Antarc*; Antarctic; Antarctica; Ice Sheet; Ice Shelf
• Online Access: https://elib.dlr.de/199307/; https://elib.dlr.de/199307/1/Ramanath_lps22_poster.pdf

The grounding line marks the transition between ice grounded at the bedrock and the floating ice shelf. Its location is required for estimating ice sheet mass balance [Rignot & Thomas, 2002], modelling of ice sheet dynamics and glaciers [Schoof 2007], [Vieli & Payne, 2005] and evaluating ice shelf stability [Thomas et al., 2004], which merits its long-term monitoring. The line migrates both due to short term influences such as ocean tides and atmospheric pressure, and long-term effects such as changes of ice thickness, slope of bedrock and variations in sea level [Adhikari et al., 2014]. The grounding line is one of four parameters characterizing the Antarctic Ice Sheet (AIS) ECV project within ESA’s Climate Change Initiative (CCI) programme. The grounding line location (GLL) geophysical product was designed within AIS_CCI and has been derived through the double difference InSAR technique from ERS-1/2 SAR, TerraSAR-X and Sentinel-1 data over major ice streams and outlet glaciers around Antarctica. In the current stage of the CCI project, we have interferometrically processed dense time series throughout the year from the Sentinel-1 A/B constellation aiming at monitoring the short-term migration of the DInSAR fringe belt with respect to different tidal and atmospheric conditions. Whereas the processing chain runs automatically from data download to interferogram generation, the grounding line is manually digitized on the double difference interferograms. Inconsistencies are introduced due to varying interpretation among operators and the task becomes more challenging when using low coherence interferograms. On a large scale this final stage of processing is time consuming, hence urging the need for automation. The grounding line is one of four parameters characterizing the Antarctic Ice Sheet (AIS) ECV project within ESA’s Climate Change Initiative (CCI) programme. The grounding line location (GLL) geophysical product was designed within AIS_CCI and has been derived through the double difference InSAR ...