EFFECTS OF HIGH FREQUENCY SURFACE WAVES ON THE STEADY EKMAN CURRENT SOLUTIONS
XU Jun-Li;SONG Jin-Bao;Institute of Oceanology Chinese Academy of Sciences;University of Chinese Academy of Sciences;
Based on the wave-modified Ekman model including the Stokes drift, wind input, and wave dissipation by Jenkins(1989), the effects of high frequency surface waves(including the short waves in capillary wave range) on the Stokes drift, and analytic steady solutions of wave-modified Ekman equation are studied. The steady solutions are obtained under the assumptions that eddy viscosity is independent of depth; and eddy viscosity increases linearly with depth using generalized Donelan and Pierson(1987) spectrum, wave dissipation of Paskyabi et al(2012), and modified wind input that is similar to Paskyabi et al(2012). The results demonstrate that high-frequency surface waves strengthen the shear of the Stokes drift at the sea surface and the effects on the Ekman solutions should not be neglected. However, the effect of angular turning on the sea surface is very small. In addition, the wave-modified solutions obtained by including high frequency waves are compared with the observations and the classical Ekman solution.