The effect of internal waves on surface wind waves 1. Experimental measurements

Abstract

Internal waves were generated by a ship using the ‘dead water’ effect in areas where the water contains a strong near‐surface density gradient. The effects of these internal waves on wind waves were examined. The principal measurements were slope statistics of the wind waves and horizontal currents in the internal waves. The effects on the wind waves were always observable from an aircraft; however, in measurements made only along the ship's track the effects of the internal waves were not always readily distinguishable from other factors that influence the wind wave field. By using statistical techniques, relationships have been established between the wind waves, the internal waves, and the wind velocity. The principal finding is that the wind wave field is relatively more sensitive to internal wave currents at low wind speeds than at high wind speeds. Numerical values are given.