Study of global ocean wave characteristics based on spaceborne SAR image cross-spectrum
Spaceborne synthetic aperture radar(SAR)is able to collect observations under all kinds of weather dur-ing day and night.Such measurements have been proven to provide significant data support for the ocean dynamics study.While SAR imaging of ocean waves is a highly nonlinear process,leading the wave signal missing along the azimuth direction.The image cross-spectrum provides a way to help investigate the ocean wave features particu-larly for their propagation direction.In this study,we extended a recently defined parameter based on SAR image cross-spectrum and analyzed the correlation of different wave scales with the local wind speed.The range peak wavenumber(wavelength)extracted from the range spectral profile is also demonstrated at the global scale based on about 4 million SAR images.It is found that this new spectral parameter could to some extent reflect the coup-ling between wind and waves.The global pattern of range peak wavenumber also illustrates evident seasonality.
万方数据
维普
