登陆北部湾北部台风对广西近岸水位变化的影响分析

Analysis of the Influence of Water Level Change in Guangxi Nearshore Caused by Typhoon Landed in the North of Beibu Gulf

关键词:  水位变化  潮流  余流  台风影响

Key words:  water level change  tidal current  residual current  typhoon impact

摘要:

根据台风"纳沙"登陆期间广西白龙半岛南面海域1 km处S1站连续的实测海流剖面资料,白龙尾F1站的水位资料和台风"榴莲"登陆期间铁山港石头埠F2站的水位资料,分析登陆北部湾北部台风对广西近岸水位变化的影响,得出如下结论:在无台风期间,S1观测点表层的最大实测潮流流速为40.0 cm/s,表层的最大余流流速为20 cm/s。在台风登陆期间,S1观测点表层的实测潮流最大流速为103.7 cm/s,表层的最大余流流速为39.7 cm/s,比无台风期间高2倍左右。但随着水深的增加,潮流和余流的流速逐渐减小;岸站F1、F2的水位变化过程是,台风登陆前,水位减至最低;台风登陆后,水位增至最大,水位的增、减变化与台风作用过程有关。同时,认为台风登陆期间广西沿岸水位的抬升和下降变化与风、港湾地形、大气重力波所产生的共振作用有着密切的关系。

Abstract:

The influence of water level change in Guangxi nearshore caused by typhoon landed in the north of Beibu Gulf was analyzed according to the continuous current profile data measured at Station S1 in the south water of Bailong Peninsula, the tidal data measured at Station F1 during typhoon Nesat landed in Guangxi nearshore and the tidal data measured at Station F2 in Tieshan Port during typhoon Durian landing. The results showed that the maximum measured current speed and residual current speed of surface layer were 40 cm/s and 20 cm/s, respectively, at Station S1 during non-typhoon.But during the strong typhoon, the maximum current speed at the surface layer reached 103.7 cm/s, and the residual current speed was 39.7 cm/s, which was about 2 times during non-typhoon.With increasing water depth, the speed of tidal current and residual current were gradually reduced. The water level at Stations F1 and F2 dropped to the minimum before typhoon landing, whereas the water level increased to the maximum after typhoon landing.Increasing or reducing of water level associated with the typhoon process.Meanwhile the change of water level rising or falling in Guangxi nearshore was closely related to the resonant interaction generated by wind, harbor terrain and atmospheric gravity waves during typhoon landing.