大气对海洋中尺度涡旋响应的数值模拟研究

Atmospheric response to the mesoscale eddy is one of hot topics in the study of mesoscale air-sea interaction, the published literatures show that most studies still remain in the stage of data analysis, numerical model is able to overcome the limitations of observational data and provide more high spatial and temporal resolution atmospheric variables for research. Although a number of physical mechanisms have proposed, but there is no clear consensus on the potential mechanisms, it still need to further strengthen the understanding of the mechanism of the atmospheric response to the ocean mesoscale eddy. Through a series of sensitivity tests, this project aims to obtain the quantitative relationship of between the mesoscale eddy and the atmospheric variables and study the effects of different atmospheric condition and ocean mesoscale eddy feature on the atmospheric response to the mesoscale eddy. The physical mechanism of ocean mesoscale eddy modulate its dynamic and thermodynamic structure in the atmospheric boundary layer is investigated from a view of energy conversion as well. Through the implementation of this project, we will have a better understanding of the mesoscale air-sea interaction and lay the foundation for the enrichment of the mesoscale air-sea interaction theory.

大气对海洋中尺度涡旋的响应是当今中尺度海气相互作用研究的热点之一，发表的文献表明目前大多数研究仍然停留在资料分析阶段，数值模式能够克服观测资料的局限，提供更多的高时空分辨率的大气变量用于研究。尽管现已提出多个物理机制来解释大气对中尺度涡旋的响应，但远未得到公认，因此，大气对海洋中尺度涡旋响应的机理认识亟待进一步加强。本项目拟通过一系列理想涡旋的实验，获得海洋中尺度涡旋与大气变量的定量关系，系统的研究不同大气背景条件以及涡旋自身特征对大气对海洋中尺度涡旋的响应的差异。并且从能量转换的角度出发，研究大气对海洋中尺度涡旋响应过程中的能量转换，深入探讨中尺度涡旋调节其上空海洋大气边界层动力和热力结构的物理机制。该项目的实施将进一步加深海洋中尺度涡旋对大气影响的认识，为丰富和完善中尺度海气相互作用理论奠定基础。

本项目利用WRF模式，通过建立理想模型，研究了大气对海洋中尺度涡旋的响应。理想模型中大气的初始状态采用静止水平均一以及f平面假设。主要结果：冷(暖)涡将导致海平面气压增加(减少)，潜热和感热通量，海表面风速、海洋大气边界层高度以及大气可降水量减少(增加)。湍流动能(TKE)收支方程显示浮力项是导致湍流动能产生的主要源。水平动量收支平衡表明,垂直混合机制在大气对海洋中尺度涡响应中起着主导作用。通过一系列的敏感性实验，研究了不同大气背景场和海洋中尺度涡特性对大气对海洋中尺度涡旋响应的影响。