Antarctic ocean tide signal restoration using differential InSAR technique

In this paper, ice shelf movements caused by ocean tides are measured by Interferometric synthetic aperture radar (InSAR) and an tidal constituent of an ice tongue in West Antarctica is estimated using ERS-1/2 tandem mission differential InSAR (DInSAR) observations. We assume that InSAR observed ocean tidal heights can be derived after correcting the InSAR data for the effect of atmospheric loading using the inverse barometric effect, solid earth tides, and ocean tide loading. Here, the dominant tidal constituent O1 underneath the Sulzberger ice shelf is estimated using 8 differential interferograms. The resulting tidal constituent is compared with a contemporary regional tide model (CATS2008a) and a global tide model (TPXO7.1). The InSAR estimated tidal amplitude agrees with both models with root-mean-square (RMS) differences of <; 2.2 cm and the phase estimate corroborating both tide models to within 8°. We conclude that fine spatial scale (~200 m) Antarctic ice shelf ocean tide determination is feasible for dominant constituents using C-band ERS-1/2 tandem mission InSAR.