What are the mechanisms for non-Bragg scattering from water wave surfaces?

Experimental data obtained in the past several years have provided conclusi ve evidence that non-Bragg scattering plays a major role in X-band microwav e backscatter from water wave surfaces, and non-Bragg scattering events are especially noticeable at small grazing angles, for wind-roughened surfaces , in the presence of breaking waves. We have conducted scattering experimen ts under a variety of wind wave conditions in an attempt to determine the d ifferent mechanisms which contribute to non-Bragg scattering. At small graz ing angles we find that non-Bragg scattering is due to fast scatterers gene rated by the wave breaking, and with increasing wave steepness and surface roughness, mechanisms of multiple scattering and multipath interference bec ome increasingly important.