吕宋海峡区域中尺度涡调制跨等密度面混合的机制研究

Diapycnal mixing plays a key role in regulating Meridional Ocean Circulation, transport of material and energy, and global climate change. Mesoscale eddy with huge energy is one of the most important factors to modulate mixing variability in space and time via interacting with bathymetry and internal wave. There are significant mesoscale eddies, complex and abrupt bathymetry, multiple internal waves over the Luzon Strait area, which is considered as a natural testing ground to study the mechanism via which mesoscale eddy modulates mixing variability. .Based on the measurement of high resolution bathymetry, the processes of mesoscale eddy, internal wave and mixing, along with numerical simulation and theoretical research, this project plans to examine the spatial and temporal variability of mixing over the Luzon Strait area, explore the mechanism via which mesoscale eddy interacts with bathymetry and generates lee wave and near-inertial internal wave, reveal the energy cascade process between mesoscale eddy and internal wave, and hence clarify mixing process and mechanism over the Luzon Strait area, along with its influence on the exchange of water, material, and energy between the South China Sea and the Pacific.

跨等密度面混合是调控大洋热盐环流的关键过程，同时对海洋质量和能量输运、生态环境及全球气候变化具有重要作用。而蕴含巨大能量的中尺度涡通过与地形作用生成内波，及与内波相互作用发生能量级串已成为调制混合时空分布的重要因素之一。吕宋海峡区域中尺度涡显著、地形复杂突变、多种内波共存，是开展中尺度涡调制混合机制研究的天然试验场。.本项目围绕吕宋海峡区域中尺度涡对混合调制机制这一关键问题，开展针对性的高分辨率海底地形与中尺度涡、内波及混合等过程的现场观测，结合数值模拟与理论研究，阐明混合的三维空间结构及时间变异基本特征，探究中尺度涡与地形作用生成背风波及近惯性内波的机制，探明中尺度涡与内波之间的能量级串过程，揭示吕宋海峡区域混合过程与机理及考量其对南海与太平洋水体、物质与能量交换的作用具有重要的科学意义和应用价值。

项目围绕南海、吕宋海峡区域中尺度涡对混合调制机制这一关键问题，开展了针对性的中尺度涡、内波及混合等过程的现场观测，结合数值模拟与理论研究，揭示了南海混合三维空间结构与时间变化规律，构建了混合与南海深层水涌升之间的自洽关系；探究了南海上层亚中尺度运动生成机制与演变规律，探明了中尺度能量经亚中尺度运动至微尺度混合的能量级串通道，建立了亚中尺度与微尺度过程的联系；给出了南海四维内波谱的特征，探讨了参数化方案在南海上层水体的适用性。项目成果阐明了南海、吕宋海峡深层混合的多种驱动机制，对南海与太平洋水体、物质与能量交换研究具有重要的科学意义和应用价值。