涌浪作用下的大气边界层对海气界面动量通量影响研究

The specific influence of swell wave on atmospheric boundary layer can generate upper momentum from ocean to atmosphere, which lead to the invalidity of traditional Monin-Obukhov Similarity Theory (MOST) and the departure between wind stress direction and wind direction and increase the uncertainty for accurate parameterization of momentum. However, most of present studies focus on neutral condition while it is shown that the buoyancy effect is another key factor that influences the atmospheric boundary layer, thus earlier studies cannot give a comprehensive understanding of influence of swell on momentum; on the other hand, it also need a new turbulent closure method to numerical simulate the influence of swell wave on atmospheric boundary layer because closure method in constant flux model does not include swell effect..To solve above problem, we try to use the data observed from a platform located at Maoming to study the influence of swell wave on atmospheric boundary layer by considering buoyancy effect and give the relationship between swell wave-induced stress and wave age or wave steepness; then a new turbulent closure method for constant flux model is constructed to simulate the influence of swell on momentum. Our method will increase the accuracy of momentum for other coupled air-sea model.

涌浪作用下的边界层比较特殊，其激发的从海洋到大气传输的动量，造成了传统Monin-Obukhov相似理论的不适用以及风应力偏离主风方向等问题，为准确的参数化海气界面动量通量带来很大不确定性。目前此问题的研究主要集中在中性条件下，但分析表明边界层中的浮力不能忽视，将研究限定在中性条件下很难对客观实际边界层进行全面揭示；在数值模拟方面，常通量模型中的湍流封闭方案由于未考虑涌浪效应造成涌浪情况下不适用，因此需要建立合理的湍流封闭方案来准确的理解涌浪对边界层的作用。.针对上述问题，本项目拟采用茂名海上综合观测平台数据，系统的分析不同稳定度下涌浪对边界层作用物理规律，给出不同稳定度下涌浪波生雷诺应力与波龄、波陡的关系；在此基础上寻求合理的湍流封闭方案，建立适用于不同稳定度的常通量模型，分析涌浪对海气界面动量通量的影响。

本项目项目通过收集茂名海上平台大气湍流数据和海浪观测数据，其中大气湍流数据包含4层超声风速仪，高度分别是8 m、20 m、28 m以及36 m，观测频率为20 Hz；海浪由浪龙（AWAC）进行观测，分析海浪对近海面大气边界层湍流的影响，并给出了海浪和风向不一致时海浪对风应力方向的调制规律，据此探讨了海浪边界层中的湍动能收支方程，发现涌浪时是造成湍收支不平衡的主要因素，并提出了相似理论只能刻画海浪边界层内剪切和浮力湍流的观点。上述结果以第一作者、通讯作者在《Journal of Physical Oceanography》、《Journal of the Atmospheric Sciences》、《Journal of Geophysical Research: Oceans》、《Acta Oceanologica Sinica》等杂志发表7篇。