吕宋海峡及其周边海域潮波和内潮耗散的数值研究

The surface tides provide energy for internal tide generation. The conversion of barotropic tidal energy to internal tides plays an important role in the ocean energy balance. In the deep water area, the bottom friction dissipation cannot represent the dissipation of tidal energy sufficiently. The tidal energy dissipation also occurs through the scattering of surface tides into internal tides, which is called internal tide dissipation. The Luzon Strait (LS) has strong tidal energy dissipation and internal tides, but most numerical studies on barotropic tides do not consider the effect of internal tide dissipation. Tides and internal tides in the LS can influence the tides and currents in the South China Sea (SCS). This research will build a 3-D tidal and adjoint model near the LS. A parameterization of internal tide dissipation is added to the traditional tidal equations, considering the internal tide dissipation on the influence of the tidal wave system. The internal tide dissipation coefficient is optimized by adjoint method. According to the numerical results, the tidal energy dissipation in the LS is analyzed, and the rate of the barotropic tidal energy conversion to the internal tides is calculated. The effect of internal tide energy flux in the LS on the internal solitary waves in Northern SCS is studied. The obtained distribution of internal tide dissipation will provide technological support for the study of ocean mixing.

正压潮为内潮的产生提供了能量，研究正压潮向内潮的转换对海洋中的能量收支平衡起着重要作用。在深水处，仅考虑底摩擦耗散不能充分体现潮能耗散的实际情况，还必须考虑表面潮向内潮转换时的能量损失，即内潮耗散。吕宋海峡潮能耗散较强，内潮多发，大部分正压潮数值模拟中都没有考虑内潮耗散的作用。吕宋海峡处的潮波和内潮对南海潮波系统和环流结构有重要影响。本项目拟建立吕宋海峡及其周边海域三维潮波模式及其伴随同化模式，并在传统维潮波方程的基础上加入内潮耗散项，考虑内潮耗散对潮波系统的影响。通过数值试验，利用伴随同化方法优化内潮耗散系数。基于数值模拟结果，分析吕宋海峡及其周边海域潮能耗散特征，估算正压潮能向内潮的转化率。分析吕宋海峡内潮能通量对南海北部内孤立波产生的影响。模拟得到的内潮耗散为研究海水混合提供了科技支撑。

吕宋海峡潮能耗散较强，内潮多发，吕宋海峡处的潮波和内潮对南海潮波系统和环流结构有重要影响。本项目利用卫星高度计数据和定点连续观测数据分析了吕宋海峡附近海域内潮特征，并利用卫星高度计数据和验潮站数据分析得到的调和常数评估了全球大洋潮汐模式在吕宋海峡附近海域的准确度。建立了潮波模式及其伴随同化模式，并在传统维潮波方程的基础上加入内潮耗散项，考虑内潮耗散对潮波系统的影响。基于数值模拟结果，分析了吕宋海峡及其周边海域潮能通量和潮能耗散特征，揭示了正压潮能向内潮的转换对海洋中等能量收支平衡起着重要作用。建立了一套潮致混合参数化方案，对海洋环流模式的调整起着重要作用。