Microwave scattering distributions from a rain-roughened water surface: measurements and modelling

Probability density distributions (pdf) of microwave scattering from a water surface roughened by rain are presented. The data were obtained at the NASA/GSFC Rain-Sea Interaction Facility using Ka- and Ku-band radars (VV polarization and 30 degrees incidence angle). Mean and standard deviations of the radar time series vary systematically with rainfall rate, which ranged up to 200 mm/hr. An analysis of the pdfs shows that the Erlang distribution, a function of these two parameters, reliably depicts the measured pdfs.