Empirical Removal of Tides and Inverse Barometer Effect on DInSAR From Double DInSAR and a Regional Climate Model

• Published in: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
• Main Authors: Glaude, Quentin, Amory, Charles, Berger, Sophie, Derauw, Dominique Maurice, Pattyn, Frank, Barbier, Christian, Orban, Anne
• Format: Article in Journal/Newspaper
• Language: English
• Published: Institute of Electrical and Electronics Engineers
• Subjects: Antartica; differential synthetic aperture radar (SAR) interferometry (DInSAR); Antarctica; double DInSAR (DDInSAR); Ice shelf; https://purl.org/becyt/ford/1.5; https://purl.org/becyt/ford/1; https://purl.org/becyt/ford/1.3; Antarctic; Dronning Maud Land; East Antarctica; Liège; Maurice; Roi Baudouin; The Antarctic; Antarc*; antartic*; Ice Sheet; Ice Shelf; Ice Shelves
• Online Access: http://hdl.handle.net/11336/146917

Ice shelves-the floating extensions of the Antarctic ice sheet-regulate the Antarctic contribution to sea-level rise by restraining the grounded ice flowing from upstream. Therefore, ice-shelf change (e.g., ice-shelf thinning) results in accelerated ice discharge into the ocean, which has a direct effect on sea level. Studying ice-shelf velocity allows the monitoring of the ice shelves' stability and evolution. Differential synthetic aperture radar interferometry (DInSAR) is a common technique from which highly accurate velocity maps can be inferred at high resolution. Because ice shelves are afloat, small sea-level changes-i.e., ocean tides and varying atmospheric pressure (aka inverse barometer effect) lead to vertical displacements. If not accounted for in the interferometric process, these effects will induce a strong bias in the horizontal velocity estimation. In this article, we present an empirical DInSAR correction technique from geophysical models and double DInSAR, with a study on its variance propagation. The method is developed to be used at large coverage on short timescales, essential for the near-continuous monitoring of rapidly changing areas on polar ice sheets. We used Sentinel-1 SAR acquisitions in interferometric wide and extra -wide swath modes. The vertical interferometric bias is estimated using a regional climate model (MAR) and a tide model (CATS2008). The study area is located on the Roi Baudouin Ice Shelf in Dronning Maud Land, East Antarctica. Results show a major decrease (67 m·a -1 ) in the vertical-induced displacement bias. Fil: Glaude, Quentin. Université Libre de Bruxelles; Bélgica. Université de Liège; Bélgica Fil: Amory, Charles. Universite de Liege. Faculty Of Applied Sciences.; Bélgica Fil: Berger, Sophie. Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung; Alemania. Université Libre de Bruxelles; Bélgica Fil: Derauw, Dominique Maurice. Universidad Nacional de Río Negro. Sede Alto Valle. Instituto de Investigaciones en Paleobiología y Geología; ...