江苏辐射沙洲水道潮流调和分析

利用改进的G·Godin潮流调和分析程序对辐射沙洲腹地水道中的29个测量站位连续2个潮周期准同步流速测量数据进行调和分析,得到9个分潮的调和常数及椭圆要素,对M2分潮潮流空间分布特征进行了分析。该海域M2分潮占优,潮流类型为正规半日潮。水道水流表现为往复流运动,主流向与岸线或水道的走向一致。流矢旋转在空间上表现较为复杂,在表层多体现为顺时针方向旋转运动。分析发现地形因素对中、底层旋转方向有较大影响。根据分析结果,对所测站位M2分潮潮流迟角和潮流浅水影响因子进行了计算分析。潮流浅水影响在沙脊及浅滩、浅沟上相对较大,浅水分潮影响随水深向下而增大。

HARMONIC ANALYSIS ON TIDAL CURRENT IN TIDAL CHANNEL OF RADIAL SAND RIDGES OFF JIANGSU COAST

Tidal current data during 1998 fall and 2000 spring in 29 stations on radial sand ridges off Jiangsu coast of China were analysed using tidal current harmonious program from which tidal harmonious constants of 9 constituents were determined; and the elliptic factors of tidal current and tidal current in each site were calculated and analysed. The tidal cur- rent elliptic factors of the M2 component in surface, middle, and near-bottom water layers at each site were analysed. The result shows that, in the study region, M2 was a dominant component of tidal current in type of regular semidiurnal tide. The overall direction of tidal current was along the tidal channels with complicated pattern of current vector rotation. The vector rotation in upper water layer was mainly clockwise; and in other layers, the rotations were affected obviously by marine to- pography. In addition, the phase lags of all the water layers were compared, and the results show that, in sand ridge, shoal, and groove areas, the shallow water component of tide were affected clearly increased downward in deeper places.