Analysis of characteristics and mechanism of current system on the west coast of Guangdong of China in summer

On the basis of data of drifting bottles' tracks and the current measured in anchored stations,as well as temperature and salinity observed in cruise investigations and coastal stations,ADCP current data and AVHRR surface sea temperature(SST) data on the western coast of Guangdong,synthetic results of analysis showed that the coastal currents in the west of the mouth of the Zhujiang River were mainly westward in summer,which constituted the north branch of cyclonic gyre in the east of the Qiongzhou Straits.Part of its water flowed westward into the Beibu Gulf through the Qiongzhou Straits.The coastal current pattern was not identical with the traditional current system which flowed westward in the Qiongzhou Straits in winter and eastward in summer.The summertime's coastal current was always westward,maybe temporarily turning northeast only when the southwest wind was strong.The important characteristics of coastal current on the western coast of Guangdong,in the Qiongzhou Straits and in the north of the Beibu Gulfwere analyzed and their mechanisms also were explained.