Generation of Internal Tide Under Weak Topography Approximation——II.Influence of Water Depth on Energy Flux of Internal Tide Under Rough Topography Conditions

Previous studies have drawn a conclusion on the effect of water depth on internal tide energy flux that the reflection of internal tide from the sea surface in the ocean of finite depth greatly reduces the transfer of energy flux from barotropic tide to internal tide,that is,for a given topography,the energy flux obtained on the assumption of unlimited depth ocean is the upper limit for the energy flux of internal tide generated over a given topography.The previous studies were concerned mainly with the smooth topography,and the real oceanic topography is always relatively rough,so this study explores the variations in energy flux of internal tide generated over a rough topography with water depth.Five rough topographies are chosen for this study,and they are cosine topography,white noise topography,the Gaussian seamount superimposed by a small-scaled cosine topography,the Gaussian seamount superimposed by a small-scaled white noise topography and the Gaussian seamount superimposed by a small-scaled white noise topography and a small-scaled cosine topography.It is shown from the study results that the energy fluxes of internal tide generated over the five rough topographies in the finite depth ocean can be greater than those obtained on the assumption of unlimited depth ocean.Therefore,the previous conclusion that the energy flux obtained on the assumption of unlimited depth ocean is the upper limit for the energy flux of internal tide generated over a given topography is not applicable to the rough topography although the conclusion is correct for the smooth topography.