Influence of Mean Wind Direction on Sea Surface Wave Development

Abstract

Momentum flux measurements made from an instrumented ocean buoy indicate that the surface drag coefficient CD is strongly dependent on changes in mean wind direction. A change in mean wind direction is accompanied by a change in wave propagation direction and associated variations in wave steepness and stage of wave development. From simultaneous wind-stress and wave measurements a critical value for the relative motion of air and surface waves is suggested beyond which the dominant waves reach the fully developed stage and the drag decreases.