Importance of ocean tidal load corrections for differential InSAR

Large time series of interferometric synthetic aperture radar (InSAR) measurements make it possible to detect slow tectonic motions of the Earth's surface on the order of millimeters per year. Here, we illustrate the importance of correcting InSAR data for the effects of ground displacements due to ocean tidal loads (OTL). These loads can cause displacement gradients greater than 3 cm per 100 km, which is larger than the accuracy of InSAR techniques and can be a significant percentage of the measured displacement due to slow tectonic processes. We demonstrate the importance of OTL with predicted displacements from selected regions of tectonic interest. Citation: DiCaprio, C. J., and M. Simons (2008), Importance of ocean tidal load corrections for differential InSAR, Geophys. Res. Lett., 35, L22309, doi: 10.1029/2008GL035806.