海洋中尺度涡旋的拉格朗日输运

项目名称： 海洋中尺度涡旋的拉格朗日输运

项目编号： No.41476022

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 天文学、地球科学

项目作者： 董昌明

作者单位： 南京信息工程大学

项目金额： 96万元

中文摘要： 具有高动能、强垂向创透力的海洋中尺度涡旋对全球和海盆尺度的水平热量、淡水以及海水物质输运均具有重要贡献，一直以来属于国际热点和前沿课题。与经典海洋学估算涡致热量输运的欧拉动力框架不同，作者与其合作者最近首次提出并初步证实涡旋本身运动所产生的输运是涡致热量和淡水输运最主要的部分，从而可以在拉格朗日运动框架下沿逐个涡旋的拉格朗日运动轨迹计算热量和淡水输运，即涡旋的拉格朗日输运。我们认为涡旋的保守性和耗散性决定了其拉格朗日输运的能力。本项目拟采取理论分析和数值实验相结合的方法，研究涡旋的搬运能力与涡旋的特征参数之间的定量关系。基于这些定量关系和多年分辨涡旋的再分析数值产品，计算全球涡致热量、淡水和海水物质输运的时空变化，并且通过大量涡致输运和平均场的样本的分析改进涡致输运的参数化。通过这一项目的实施，我们将更好地认识中尺度涡旋在全球海洋热盐和物质分布中的作用，以及气候模式分辨中尺度涡旋的重要性。

中文关键词： 中尺度；涡旋；拉格朗日输运；数值模型

英文摘要： With high kinetic energy and strong vertical penetration capability, oceanic mesoscale eddies play a significant role in horizontal transports of heat, freshwater and water mass in both global and basin scales and its study has been receiving intensive attentions in international oceanic community. The PI and his collaborators recently initiates and preliminarily demonstrates that the global eddy-induced heat and freshwater transports are mainly due to individual eddy movements, which indicates that the eddy-induced het and freshwater transport can calculated along individual eddy's Lagrangian trajectory. We propose a hypothesis that the capability of an eddy's Lagrangian transport depends on its conservativity and diffusivity. To test the hypothesis, we will conduct a theoretical analysis and a series of idealized numerical experiments as well to determine the quantitative relationship between an eddy's transport capability and eddy's characteristics. Based on these quantitative relationships, the proposed project will calculate the global Lagrangian eddy transports of heat, freshwater and materials based on an eddy-resolved global reanalysis numerical product and explore the spatial and temporal distribution of global eddy-induced heat, freshwater and material transports. Based on the analysis of tremendous samples of eddy-induced transport and mean fields, we will improve the parameterization of eddy-induced transports. Through the implementation of the project, we will better understand the role of mesoscale eddies in global heat and freshwater distribution and importance of a global climate model resolving mesoscale eddies.

英文关键词： Mesoscale;Eddy;Lagrangian transport;Numerical modeling