南海夏季环流机制的数值试验研究

A STUDY ON CIRCULATION MECHANISM OF SOUTH CHINA SEA IN SUMMER BY NUMERICAL EXPERIMENTS

用一个三维、自由表面、斜压海洋模式,通过数值试验的方法对南海夏季的环流特征及其形成机制进行探讨。结果表明,产生南海南部反气旋式环流的主要机制是西南季风的驱动,斜压效应起到了增强环流强度的作用;海底地形和黑潮的强迫是形成"南海暖流"和台湾海峡中东北向流的主要原因,而斜压效应和海底地形是形成夏季"南海暖流"右侧偏西向流的主要原因;南海北部的气旋式涡旋是在黑潮、海底地形和斜压效应等因素共同作用下形成的。

A three-dimensional, baroclinic model with a free surface has been employed to study the circulation characteristics of the South China Sea (SCS) and its mechanism in summerby numerical experiments. The results show that the anticycloniccirculation in the southern SCS is mostly driven by the southwest monsoon, and its intensity is strengthened by baroclinic effect; the Kuroshioforcing and the bottom topographic effect are the maincauses for producing the SCSWarm Current and the current flowing northeastward throughthe Taiwan Strait; baroclinic andbottom topographic effects are the main causes for forming thecurrent flowing in right handof the SCSWarm Currentin summer; and the cyclonic eddy in the northern SCS is formeddue to the joint actions of Kuroshioforcing, bottom topographic effectand baroclinic effect.