一次西南印度洋热带气旋过程发展机制的数值研究

NUMERICAL ANALYSES ON DEVELOPMENT MECHANISM OF A TYPICAL TROPICAL CYCLONE OVER SOUTHWESTERN INDIAN OCEAN

本文利用尽可能多的观测资料和WRF-3.4.1模式(Weather Research and Forecasting Model)对2012年1月19日至28日发生在西南印度洋上空的1次强热带气旋进行了研究,并分析其时空结构和发展机制。对该热带气旋的移动路径、强度及内部结构的数值模拟结果与实际符合较好。分析表明,感热和凝结潜热贯串于热带气旋发展的整个过程,其中感热对气旋发展的影响较弱,凝结潜热是气旋发展的主要能量来源,CISK机制可解释该热带气旋的发展过程。

The structure, evolution, and physical mechanism of a strong tropical cyclone that occurred over the Southwestern Indian Ocean from 19 to 28 January 2012 were investigated by using all types of observational data and WRF-3.4.1（Weather Research Forecasting Model） model. The model reproduced the tropical cyclone reasonably including the moving path, strength and inner structure. The analysis based upon the simulation result indicated that the sensible heat flux and latent heat of condensation run through the whole process of tropical cyclone development. The simulating result shows that the latent heat of condensation is the main source of energy for development of the cyclone, and the role of sensible heat flux is relatively weak. The CISK（Conditional Instability of Second Kind） mechanism can explain the development of this tropical cyclone well.