Inferring surface roughness and breaking wave properties from polarimetric radar backscattering

Ocean surface roughness and surface wave breaking are two common parameters important to the studies of microwave ocean remote sensing and air-sea interactions. For example, remote sensing of ocean surface vector winds by radars and radiometers makes implicit use of the property that the normalized radar cross section (NRCS) and the sea surface brightness temperature are modified by the surface roughness and wave breaking; and both oceanographic properties are closely influenced by the wind. For air-sea interaction processes such as gas transfer or sea spray aerosol generation, the boundary layer turbulence properties are closely associated with the surface roughness, and wave breaking represents a dominate process of turbulence generation and air entrainment in the upper ocean layer.