Finite difference model for modeling sea surface current from RADARSAT-1 SAR data

Abstract

This study introduces a new approach for modelling sea surface current variation using synthetic aperture radar (SAR). SAR Doppler frequency shift was computed by the ambiguous estimation and Wavelength Diversity Ambiguity Resolving algorithm (WDAR) and Multi Look beat Frequency (MLBF) RADARSAT-1 SAR standard mode data. In situ current measurements have been collected by using wave rider buoy (AWAC). The current velocity then estimated by conversation of residual Doppler Centroid by performing second order polynomial model. The second-order accurate dispersive Lax-Wendrof was used to determine the spatial variation of sea surface current in RADARSAT-1 SAR data. The study shows that there is a significant relationship between in situ current measurements and sea surface current estimated by WDAR and MLBF techniques. The high accuracy is shown with mean root mean square error (RMSE) of ± 0.11 m/s. It can be concluded that the integration between WDAR and MLBF techniques and Euler finite element model is good tool for modelling sea surface current variation in RADARSAT-1 SAR images.