孟加拉湾上层环流研究综述

综述了孟加拉湾上层环流研究的主要成果并指出,研究海区环流与季风转换不完全同步。在西南季风期间,南、北海区各有一气旋式环流;在秋季季风过渡期间,出现海湾尺度的气旋式环流;在东北季风期间,气旋式环流减弱北移,南部则为一反气旋式环流控制;春季与秋季的情形相反,整个湾出现一海湾尺度的反气旋式环流。研究海区环流的变异主要受季风、赤道远地作用和浮力通量等复杂外源作用的影响。东印度沿岸流的季节变化与季风转换也不同步,局地风、内部Ekman抽吸、远地沿岸风及赤道远地作用的影响对沿岸流周年变化有重要作用。孟加拉湾上层环流年际变化显著,此年际变化主要受赤道风场的影响。

Review of Study on Upper Ocean Circulation in the Bay of Bengal

In this paper,the main study results of upper ocean circulation in the Bay of Bengal are sumarized,and it is pointed out that the variation in circulation in the area is out of phase with that in Indian monsoon.During the southwest monsoon period,two cyclonic gyres occur in the southern and northern sea areas,respectively;during the autumn monsoon transitional period,a baywide scale cyclonic gyre occurs;during the northeast monsoon period,the cyclonic gyre decays to move northward,and the anticyclonic gyre occupies the southern sea area;in spring,a baywide scale anticyclonic gyre occurs in the sea area.The variation in circulation in the sea area is influenced mainly by the monsoon,remote forcing from the equatorial sea area and buoyancy flux.The seasonal variation in the east India coastal current(EICC) is out of phase with that in the Indian monsoon,and the annual variation in the EICC is influenced mainly by the local wind,interior Ekman pumping,remote alongshore wind and remote forcing from the equatorial sea area.The interannual variability in the upper ocean circulation in the Bay of Bengal is obvious and is influenced mainly by the equatorial wind field.