舟山本岛南部附近海域潮汐潮流特征分析

The Characteristics of Tidal Currents near the Southern Coast of Zhoushan Island

文章基于沈家门长期潮位站、长峙岛临时潮位站的观测资料和对舟山本岛南部海域多个站位实测的潮流基础数据,采用调和分析法对潮汐潮流进行特征分析。舟山本岛南部附近海域潮汐类型属于规则半日潮,潮差变化和日不等现象明显,有一定的潮汐浅海作用。潮流类型属于以往复流为主的规则半日浅海潮流,实测潮流中涨落潮流速不等、历时不等现象显著,最大流速、平均流速均是大潮大于小潮,涨潮流历时长于落潮流历时,潮流变化主要受协振波所控制,流向在涨落潮方向波动。

The characteristics of the tidal currents were analyzed by the method of harmonic analysis based on the observation information of long-term tidal level station at Shenjiamen,temporary tidal level station at Changzhi Island and basic data of several stations in the southern coast of Zhoushan Island.The tidal type in the sea near the southern coast of Zhoushan Island is regular semidiurnal tide,which has obvious variation of tidal range and diurnal variation,in addition,there is a certain tidal shallow sea effect.The current type is the regular half-day shallow sea trend with reciprocating flow.The measured tidal currents have different tidal current velocities and diachronic phenomena.The maximum flow velocity and average velocity of spring tide both surpass the neap tide.The duration of flood is longer than that of ebb tide.The phenomenon of fluctuating tidal current varying in velocity and duration is remarkable in the observed tidal current.The variation of the tidal current is mainly controlled by the co-oscillation wave and the direction of the flow fluctuates in the direction of the ebb and flow.