基于高频地波雷达观测的粤港澳大湾区春季海表流特征研究

Characteristics of Surface Currents in Guangdong-Hong Kong-Macao Greater Bay Area in Spring Based on High Frequency Radar Observations

基于高频地波雷达系统监测得到的海表流资料,选取907个高密度空间点,运用调和分析等方法,探究粤港澳大湾区2020年3月的潮流特征。结果表明,该海域潮流以不规则半日潮M2分潮为主,且浅水分潮影响显著。主要全日分潮和半日分潮的倾角都在120°~160°之间,即最大流速都为西北-东南流向,表现为向岸-离岸流动的趋势。随着与海岸线距离的增加,潮型系数和浅水系数逐渐增大,区域南部离岸区表现出不规则全日潮的特征。可能最大流速和实测最大流速的范围分别为0.33~71.01 cm/s和58.63~149.99 cm/s,其大值都分布于研究区的西北部和南部。

Based on the sea surface currents data of Guangdong-Hong Kong-Macao Greater Bay Area(GBA)in March 2020 obtained from high frequency radar(HFR),the surface currents data from 907 densely distributed points were selected to analyze the characteristics of spatial-temporal variation.Harmonic analysis and some other methods were used to explore the characteristics of tidal currents.The results show that the irregular semidiurnal tide M2 is dominant in the sea area,and the shallow-water effect is significant.The dip angles of the main diurnal and semidiurnal tides are between 120°to 160°.The direction of maximum flow rate is WN-ES,which shows the trend of shore offshore flow.As the distance to the shoreline increases,the tidal current pattern coefficient and the effect of shallow water constituents coefficient gradually increase,and the offshore area in the south of the research area shows the characteristics of irregular diurnal tide.The ranges of probable maximum current velocity and measured maximum current velocity were 0.33 cm/s to 71.01 cm/s and 58.63 cm/s to 149.99 cm/s,respectively,with the upper-end values distributed in the northwest and south of the study area.