一次江淮暴雨的热量与水汽收支诊断分析

利用MM5中尺度模式对一次江淮地区的暴雨过程进行了数值模拟，应用模拟结果诊断分析了降水区热量和水汽收支的变化。结果发现：当有强对流发生并伴有强降水时，就会有强的视热源Q1和视水汽汇Q2出现，而强的Q1与Q2和强降水区基本是对应的。在对流层深厚的中空加热层是积云对流活跃和强暴雨持续发生、发展的一种重要热力机制；对流层上半部的相对冷层为暴雨区上空积云对流提供了极为有利的热力不稳定条件。

Diagnosis of Heat and Moisture Budgets of a Rainstorm in Jianghuai

With the MM5 mesoscale model, the numerical simulation on the rainstorm over the Jianghuai is carried. The mesoscale is diagnosed using the output data of MM5 with the following findings: strong apparent heat sources Q_1 and apparent moisture sink Q_2 would appear while the strong convection occurs with heavy rainfall; Q_1 and Q_2 are basically correspondent with the regions of heavy rains; the deep and thick heating layer in the middle troposphere is the main thermodynamic mechanism for both cumulus convective activities and the successive generation and development of the severe rainstorms; the relatively cool layer in the upper troposphere provides a favorable thermodynamic condition for intensive cumulus convection over the heavy rain areas.