The Effect of Swell on the Growth of Wind Waves

Abstract A laboratory experiment has been made to clarify the effect of swell on the growth of wind waves, when the swell is propagating against the wind. It is shown that the growth of wind waves is not much affected by the swell when the swell steepness is small, but it is intensified by the swell when the swell steepness increases. This phenomenon is in clear contrast to the attenuation of wind waves by the swell propagating in the direction of the wind (Mitsuyasu 1966, Phillips & Banner 1974).