大亚湾的潮汐动力学研究--I.潮波系统的观测分析与数值模拟  

Study on the tidal dynamics in Daya Bay, China -- Part I. Observation and numerical simulation of tidal dynamic system

作　　者：武文[1] 严聿晗 宋德海[2] WU Wen;YAN Yuhan;SONG Dehai(College of Oceanic and Atmospheric Sciences, Ocean University of China, Qingdao 266100, China;Key Laboratory of Physical Oceanography, Ministry of Education, Ocean University of China, Qingdao 266100, China)

机构地区：[1]中国海洋大学海洋与大气学院,山东青岛266100 [2]中国海洋大学物理海洋教育部重点实验室,山东青岛266100

出　　处：《热带海洋学报》2017年第3期34-45,共12页Journal of Tropical Oceanography

基　　金：国家重点基础研究发展计划(2015CB452905);中国博士后科学基金第8批特别资助(2015T80742)~~

摘　　要：文章作为大亚湾潮汐动力学系列研究的第一部分,展现了大亚湾水动力的最新观测结果,并借助于不规则三角网格海洋模式建立了高时空分辨率的三维潮汐潮流数值模型,重现大亚湾潮位和潮流变化状况。结合实测资料与模拟结果,得到了较以往更为精细的大亚湾潮波系统特征。浅水分潮,尤其是六分之一日分潮在大亚湾内快速增长,成为大亚湾潮波系统的显著特征。在大亚湾范和港M_6分潮振幅达到与M_4、S_2分潮相同的量级。大亚湾外开阔海域的潮流以旋转流为主,但进入湾内后潮流椭圆迅速扁平化,往复流占据主导。在湾内主要潮流通道内,M_6潮流椭圆主轴流速超过了M_4和K_1分潮。潮能通量分析揭示了大亚湾内高频分潮的强耗散,M_6分潮的能量耗散率和半日周期内耗散的总能量均超过了M_4、M_2和K_1分潮。观测到的欧拉余流表现出其湾内不一致的大小潮变化以及湾外所受沿岸流的影响。模拟出的欧拉余流则揭示了大亚湾内的余流多涡旋结构和水体弱交换能力。This paper is the first part of our studies on the tidal dynamics in Daya Bay(DYB),China.It illustrates the recentfield work results.We establish a three-dimensional,fine resolution,unstructured grid,coastal ocean model to reproduce thetides in DYB.The combination of observation and simulation in this paper gives a better description on the tidal dynamicsystem in DYB than previous studies.Shallow water tides,especially the sexta-diurnal tides increase fast in DYB,whichbecome the most notable characteristic of DYB tidal dynamic system.In the Fanhe Harbour at the northeastern DYB,theamplitude of M6tide reaches the maximum,at the same order as M4and S2tides.In the open sea outside DYB,the tidalcurrent is dominated by a rotating shape;but once the current enters the bay,it turns to rectilinear quickly.In the main tidalchannels,the magnitude of M6tidal current is even larger than those of M4and K1tides.The distribution of tidal energy fluxindicates larger tidal energy dissipation for higher frequency tides.In DYB,both the tidal energy dissipated in a semi-diurnal period are much larger by M6tide than by M4,M2and K1tides.The observed Euler residualcurrents show different spring-neap variation in magnitude inside DYB,and reveal the influence of the coastal current outsidethe bay.The numerical simulation shows a multi-vortex of residual current,and indicates poor water exchange in the bay.

关 键 词：大亚湾 潮波系统 浅水分潮 六分之一日分潮 数值模拟 

分 类 号：P731.2[天文地球—海洋科学]