OBSERVED DIRECTIONAL CHARACTERISTICS OF THE WIND, WIND STRESS, AND SURFACE-WAVES ON THE OPEN-OCEAN

Sonic anemometer data were taken during the Surface Waves Processes Program (SWAPP) in March 1990 in the North Pacific. Measurements of the wind stress vector span several strong wind events. Significant angles between the wind stress vector and the mean wind vector are seen. Simultaneous measurements of the directional wave field were made with a su;face scanning Doppler sonar: The data suggest that the wind stress direction is influenced by the direction of the surface waves, especially for stronger winds. Overall, the stress vector lies between the mean wind and the mean wave directions. At the higher wind speeds (over 8.6 m/s), there is a nonzero correlation between the variations in wave directions and stress directions as well. Finally, the stress and wave component directions have similar frequency dependence over the frequency band where wave energy is nonnegligible, suggesting a dynamic link.