利用伴随同化方法优化南海内潮观测站位的研究

Optimization of the Position of Observation Stations in the South China Sea with Adjoint Assimilation Method

基于南海现有的潜标布放位置,采用等密度坐标内潮伴随同化模型,对潜标布放位置进行了优化研究。实验结果表明:东、北两处的开边界条件对于该区域的内潮数值模拟最为关键,位于吕宋海峡附近的站点携带了更多与开边界条件相关的信息,并且由东北向西南依次递减;东开边界条件在全海域的纬向流速、北部海域的径向流速模拟中起着主导作用。基于现有的60个站点反演开边界条件,难以准确模拟该区域的内潮。实验结果表明,在人为的增加5个站点后,3组站点的绝对平均误差均有一定程度的减小,并且在地形变化较为强烈的区域放置呈断面状的站点可以大幅度提高所有站点处的模拟结果,从而提高该区域内潮的模拟精度。

Based on the existing mooring position in the South China Sea,by using isopycnic-coordinate internal tidal model with adjoint assimilation method to optimize the position of observation stations.The experimental results show that the east and north open boundary condition is vital to the numerical simulation of internal tidal in this area,and stations near the Luzon strait have more relative message of open boundary condition,which decrease from northeast to southwest.The east open boundary condition play the leading role in the zonal flow velocity of whole sea area,and the radial velocity of the north sea area.And the existing 67 stations are not enough to accurate the internal tidal simulation in this area,but after added 5 stations artificially,the mean absolute error of three group of station decreased.It can be concluded that put the section shape of stations on the topography which change strongly can increase the simulation result of all stations substantially,thereby increasing the simulation precision in this sea area.