Global operational remote sensing andmodelling of ocean

An overview is given of current operational methods for retrieving two-dimensional ocean wave spectra from near real-time ERS-1 SAR wave mode (SWM) imagette spectra. The SWM data quality and performance of the WASAR algorithm are assessed. Sensitivity analyses and validation studies are performed using two-dimensional NOAA buoy data as well as TOPEX and ERS-1 altimeter-derived signiicant wave heights. An inter-comparison between SWM-retrieved and WAM model spectral parameters shows a good overall agreement, however with a small but systematic over-prediction of windseas and underprediction of swell by the WAM. While the former can be explained by to too strong forcing by the ECMWF wind elds, the latter is attributed to too strong damping of swell by the WAM. Some evidence is found of a misalignment between the wind speed vector and the wind stress in the presence of swell.