IMPROVEMENT OF KOMPSAT-5 SEA SURFACE WIND WITH CORRECTION EQUATION RRETRIEVAL AND APPLICATION

Abstract

KOMPSAT-5 is the first satellite in Korea equipped with X-band Synthetic Aperture Radar (SAR) instrument and has been operated since August 2013. The availability of KOMPSAT-5 is highlighted as the need of high resolution wind for coastal monitoring. However, the previous study for the estimated wind from KOMPSAT-5 showed that the accuracy is lower than other SAR satellites. Therefore, in this study, we developed the correction equation of normalized radar cross section (NRCS) for improvement of wind from KOMPSAT-5 and validated the equation compared with the buoy measurements. Theoretical estimated NRCS and observed NRCS showed linear relationship with incidence angle. Before applying the correction equation, the accuracy of the estimated wind speed showed the root-mean-square errors (RMSE) of 2.89 m s(-1) and bias of -0.55 m s(-1). The errors were significantly reduced to the RMSE of 1.60 m s(-1) and bias of -0.38 m s(-1) after applying the correction equation.