THE EFFECTS OF A SLOPING BOTTOM ON THE EQUATORIAL WAVE-INDUCED DEEP RESIDUAL CURRENTS

作     者：吴德星 

作者机构：Ocean University of Qingdao Qingdao 

出 版 物：《Chinese Journal of Oceanology and Limnology》 (中国海洋湖沼学报（英文版）)

年 卷 期：1997年第15卷第4期

页      面：314-321页

核心收录：

学科分类：0710[理学-生物学] 0908[农学-水产] 07[理学] 0707[理学-海洋科学] 0815[工学-水利工程] 

基　　金：National Natural Science Foundation of China,NSFC State Oceanic Administration,SOA 

主　　题：wave-induced Lagrangian residual current effects of bottom topography 

摘      要：Based on an inverted one-and-one-half inviscid reduced gravity shallow water model with bottom topography representing an abyssal layer under a stagnant upper layer on the equatorial β-Plane, a set of field equations governing the wave-induced Lagrangian residual currents is developed. The equations show that the wave-induced Lagrangian residual ot satisfies generalized geostrophic dynamics. The relation of meridional residual current to vertical residual current resulted from the varied bottom is similar to the Sverdrup transport relation. The tranport process of potential vorticity for zeroth order approximation is determined by the advection whose velocity is equal to that of the weve-induced Lagrangian residual current.A Kelvin wave solution and the reated solution of Kelvin wave-induced Lagrangian residual current for the case of slowly varying topography are obtained anaytically. The wave solution shows that a shoaling eastward bottom can decrease the propagation speed of the Kelvin wave and cause it to take a longer time to transmit the energy from the west to the central and easterm parts of the basin, and can also shorten the wavelength and enhance the wave amplitude. The wave-induced residual current solution reveals that the existence of a sloping bottom can result in a onier meridional component of wave-induced mesidual current and that Kelvin wave-induced Lagrangian currents’s responses to bottom variation are greater than those of Kelvin wave orbital currents.