渤黄东海潮波数值模拟

NUMERICAL MODELLING OF TIDAL WAVES IN THE BOHAI SEA, THE HUANGHAI SEA AND THE EAST CHINA SEA

利用考虑引潮力的非线性球面潮波方程，数值模拟渤黄东海的潮波运动，将计算结果与实测资料作比较。依据所得结果绘制M2，S2，K1，O1和M4的同潮图和潮流椭圆，并进行讨论。研究表明，K1和O1的同位相线在台湾附近先作顺时针方向旋转然后作逆时针方向旋转，该现象是由于大陆架和大陆坡水深分布和台湾存在的结果。同时也发现最大流速时刻比高潮时刻提前，是摩擦和旋转潮液系统中的驻波成份所引起的。对该海区的非线性潮波部分的模拟作了首次尝试。可以看出：M4有18个旋转潮波系统，其中6个作顺时针方向旋转，12个作逆时针方向旋转；在江苏南部海岸和杭州湾口的外海区域以及渤海湾和大部分的莱州湾，由M2引起的潮汐余水位为正，而在海区的其余部分这种余水位为负；由M2引起的潮汐余流总体上向南或向东南方向流动。

Tidal waves in the area were numerical modelled by the use of the non-linearspherical tidal equations with tide-generating force. The computed results were compared with the observed data. The cotidal charts and the tidal current ellipses ofM2, S2, K1, O1 and M4 are drawn and discussed based on the obtained results. It isdiscovered for the first time near Taiwan the cophase lines of K1 and O1 rotate first clockwise and then anticlockwise. Such a phenomenon is due to both the waterdepth distribution of continental shelf and slope and the existence of Taiwan. It is also found that the maximum velocity moment is in advance of the high tide moment, which is caused by friction and standing wave part of amphidromic system.This is the first attempt at modelling the non-linear part here. It can be seen fromthe results that the M4 has 18 amphidromic systems, among them, 6 rotating clockwise, 12 anticlockwise; the residual water level induced by M2 is positive in the offshore area of the Jiangsu south coast and the Hangzhou Bay mouth, and in theBohai Bay and the most part of the Laizhou Bay, whereas in the rest water area itis negative; and that the tidal residual current induced by M2 flows southwards orsoutheastwards in general.