The VIERS-1 scatterometer model

    P.A.E.M.Janssen, H.Walbrink, C.J.Calkoen, D.van Halsema, W.A.Oost
           and P.Snoeij (to be presented by P.A.E.M. Janssen).

   The VIERS-1 (Verification and Interpretation ERS-1) project has
   resulted in a new algorithm for the interpretation of the wind
   scatterometer, based on a physical model of air/sea/radar
   interaction in which the radar backscatter is calculated from
   wind and wave conditions. The model is inverted to obtain the
   wind from the radar backscatter. For operational purposes the
   model was coupled to the WAM wave model, which provides first-
   guess wave information. The performance of VIERS-1 has been
   compared with that of CMOD4, the algorithm presently in
   operational use, which is mainly based on statistical fitting.
   Using operational data it has been found that the results of
   VIERS-1 were comparable with those of CMOD4, with VIERS-1
   outperforming CMOD4 slightly at both high and low wind speeds,
   but with CMOD4 providing a somewhat closer fit in backscatter
   space.

Keywords: ESA European Space Agency - Agence spatiale europeenne, observation de la terre, earth observation, satellite remote sensing, teledetection, geophysique, altimetrie, radar, chimique atmospherique, geophysics, altimetry, radar, atmospheric chemistry