Global ENVISAT ASAR and coastal TerraSAR X Measurements of Sea State for validation of Ocean Wave Models

Abstract

Satellite Synthetic Aperture Radar (SAR) images are acquired independent of light and weather conditions on a global scale. Figure 1 shows an example of a 5 km x 10 km ERS SAR wave mode image, reprocessed from SAR raw data at DLR and its respective image spectrum.At weather centers SAR data are used to improve the two dimensional wave spectrum from a wave model by a nonlinear SAR ocean wave retrieval schemes. In the present paper new algorithms to derive sea state parameters from globally available SAR wave mode data are briefly introduced, significant wave height (SWH) is derived and used to investigate severe storms and compiled to global statistics. The empirical algorithm CWAVE is extended from use for ERS SAR data (Schulz-Stellenfleth et al., 2007) to ENVISAT ASAR wave mode images (Li et al, 2009).