Subtropical Gyres: Formation, Dynamics, and Climatology

这是一个研究副热带环流的项目，副热带环流是北半球夏季，特别是北太平洋西部在北纬12度至30度之间发生的对流层低层气旋。它们比热带气旋（tc）大，有时包含在其内部形成并在其周围以气旋方式传播的tc。研究环流的起源、气候学、结构和动力学，研究环流的时空分布及其对降水和TC成因的贡献。该项目首先确定一套适当的标准来定义亚热带环流，这样一个自动化的过程就可以用来创建它们的记录，用来确定它们的空间和季节分布、典型的大小和持续时间，以及与厄尔尼诺现象和事件以及马登-朱利安涛动相关的变化。接下来，将重点研究副热带环流的结构、演化和动力学。除了观测记录外，研究还将使用气象研究与预报（WRF）模式的模拟来检验各种物理机制对环流演变的贡献，包括与环流内对流相关的非绝热加热的地面风响应，以及随后在环流西侧增强的地表热交换。考虑到副热带环流与TC形成的关系，对副热带环流的研究具有一定的社会价值。在副热带环流内形成的台风对东亚和东南亚沿海地区构成威胁，在本奖项下进行的工作可能有助于更好地了解和预测这些风暴。此外，该项目还资助了一名研究生，从而为该科学领域的下一代研究人员做出了贡献。

This is a project to study subtropical gyres, which are lower-tropospheric cyclones occurring between 12N and 30N in northern summer, especially in the western North Pacific. They are larger than tropical cyclones (TCs), and sometimes contain TCs that form within them and propagate cyclonically around them. The work will investigate the origin, climatology, structure, and dynamics of the gyres, and study their spatial and temporal distribution and their contribution to precipitation and TC genesis. The project begins by determining an appropriate set of criteria to define subtropical gyres, so that an automated process can be used to create a record of them, to be used to determine their spatial and seasonal distribution, typical size and duration, and variations associated with El Nino and events and the Madden-Julian Oscillation. Next, the research will focus on the structure, evolution, and dynamics of subtropical gyres. In addition to the observational record, the research will use simulations from the Weather Research and Forecasting (WRF) model to examine the contributions of various physical mechanisms to gyre evolution, including the surface wind response to diabatic heating associated with convection within the gyre, and the subsequent enhancement of surface heat exchange on the western side of the gyre.Research on subtropical gyres has societal value given the association of the gyres with TC formation. Typhoons forming within subtropical gyres pose a threat to the coastal regions of East and Southeast Asia, and the work performed under this award may contribute to better understanding and prediction of these storms. In addition, the project supports a graduate student and thus contributes to the next generation of researchers in this scientific area.