Abstract:

The WRF model was used to simulate a heavy rain process occurring in the Sichuan basin caused by the southwest vortex from June 16 to 17, 2011. The reasons for the appearance and development of the southwest vortex were analyzed from the aspects of thermodynamics in boundary layer. The result shows that the ground heat flux maintained the southwest vortex during the process of southwest vortex’s development. Although the southwest vortex could be simulated by ignoring the ground heat flux, its intensity and position simulated by the model had a great difference compared with the results considering the real conditions, and the simulated results couldn’t present the actual precipitation. The development of the southwest vortex was mainly affected by the precipitation condensation latent heat, to a large extent, it determined whether a southwest vortex would form or not.

Key words:  southwest vortex, WRF model, rainstorm, thermal factors

摘要：

利用WRF模式对2011年6月16—17日由西南低涡触发的一次四川盆地强降雨过程进行模拟分析，从边界层内的热力学特征角度分析西南涡发生、发展成因。结果表明：如不考虑地面热通量，虽然能模拟出西南涡，但西南涡的强度和位置与实际情况相差较大，且模拟结果基本没有再现降水；地面加热在西南涡的发展过程中起维持作用，西南涡的发展主要受降水凝结潜热的加热作用，降水凝结潜热的释放在很大程度上决定西南涡能否形成。

关键词: 暴雨, 热力因子, 西南涡, WRF模式