AN EXPERIMENTAL-STUDY OF MICROWAVE-SCATTERING FROM RAIN-ROUGHENED ANDWIND-ROUGHENED SEAS

This paper investigates radar cross-section (RCS) characteristics of r ain- and wind-roughened sea-surfaces. We conducted experiments in labo ratory wind-wave tanks using artificial rain. The study includes light rain rates, light wind speeds, and combinations of these. A 36 Ghz sc atterometer was operated at 30-degrees incidence angle and with vertic al polarization. RCS data were obtained not only with the scatteromete r pointing up-wind but also as a function of azimuthal angle. We use a scatterometer rain and wind model SRWM-1, which relates the total ave rage RCS in storms to the sum of the average RCS due to rain plus the average RCS due to wind. Implications of the study for operational mon itoring of wind in rainy oceanic areas by satellite-borne instruments is discussed.