北部湾北部环流的季节特征

Seasonal Characteristics of Circulation in the Northern Beibu Gulf

【目的】研究北部湾环流的季节变化特征。【方法】利用2017–2018年防城港近岸海域4个航次的海流实测资料,结合卫星遥感海表温度数据和HYCOM海流再分析数据,分析北部湾环流的季节变化。【结果与结论】1)观测期间余流方向与风向基本一致,表现出风海流特征;2)夏季北部湾北部存在高温水团,余流受风生流和密度流的共同作用,密度流流速约为10cm/s;3)4个季节北部湾均为逆时针环流形态,主要受潮致余流、风生流和密度流的影响;4)冬季北部湾海域总体呈逆时针环流,但在防城港以东至北海的外海海域出现顺时针环流。

【Objective】To study the seasonal circulation characteristics in the northern Beibu Gulf.【Method】Based on current data from four voyages in Fangchenggang coastal waters from 2017 to 2018 and combined with the satellite remote sensing data of the sea surface temperature and the HYCOM current re-analysis data,the characteristics of the Beibu Gulf residual currents were analyzed.Meanwhile,the seasonal variation characteristics of the circulation in Beibu Gulf were studied by using satellite remote sensing sea surface temperature data and HYCOM current reanalysis data.【Result and Conclusion】1)During the observation period,the direction of residual current was the same as that of wind,showing the current characteristics of wind-sea current;2)During the summer observation period,there was a high temperature water mass in the northern Beibu Gulf,which was affected by both wind-driven current and density current,and the velocity of density current was about 10 cm/s;3)During the four seasons,the current in the Beibu Gulf was in counterclockwise circulation,mainly affected by tide-induced residual current,residual current and gravity current.4)In winter,the Beibu Gulf was generally in counterclockwise circulation,but clockwise circulation appeared in the offshore waters from the Fangchenggang eastward to the Beihai.