The Comparision of Ocean Wave Orbital Velocity Obtained from Four Azimuth Cutoff Methods

Abstract

In this paper, we use statistical methods to analyze the wave orbital velocity estimated by four azimuth cutoff methods based on the Envisat Advanced Synthetic Aperture Radar(ASAR) Wave mode data. The wave orbital velocity obtained by the second moment of wave spectrum from the National Data Buoy Center(NDBC) were used as the verification data. The analysis shows that the sass (the method of improving the quality of the azimuth cutoff wavelength in Stopa's paper combined with the azimuth-cutoff-based ocean wave orbital velocity inversion method mentioned in the Schulz-Stellenfleth article, sass) method achieved the lowest bias of −0.0475m/s, the minimum root mean square error (RMSE) of 0.1510m/s, the smallest scatter index(SI) of 33.62% and the maximum correlation coefficient(corr) of 0.7481. And the bias of the inversion result between the sass method and the second moment of the wave spectrum(m2) method based on ASAR data is also the smallest, which is −0.0034m/s, with the correlation coefficient better than 0.8. Therefore, the sass method is considered to be the best method among the four inversion methods based on azimuth cutoff from space-born SAR observations.