Interactions between rain and wind waves

Abstract

Effects of rain on surface waves have been investigated in a circulating wind-wave tank. Surface displacement and slope spectra under different wind velocities were measured near the upwind and downwind edges of a region with simulated rains. Spatially uniform rains of varied intensities with drop size of about 2.6 mm and spacing of 3 cm were used. Damping of surface waves by rain was observed in the frequency region of 2-5 Hz, and there was an increase in the damping rate with rain intensity. The effective eddy viscosity in the rain-induced mixed layer was found to be an order of magnitude greater than the molecular viscosity of water. -from Author