一次华南暴雨过程中不同区域降水特征的模拟分析

Simulation and analysis of precipitation in different areas of Huanan rainstorm

通过对2005年6月19—20日的一次华南大暴雨过程的诊断分析表明,本次降水过程的水汽来源有两个,一是来自于印度洋上的印度季风,另一个是来自于澳大利亚的东南信风。对不同暴雨中心的分析表明,福建北部的降水带为华南准静止锋锋面上的系统性降水,假相当位温的经向垂直剖面呈明显的Ω型结构,而广东河源附近的暴雨中心为暖区对流性降水,低层为强的不稳定。利用ARPS模式对这次暴雨过程进行了数值模拟,结果表明,锋面雨带主要来自于网格降水的贡献,而对流性降水主要来自于次网尺度降水的贡献。

Diagnose analysis of a Huanan storm rainfall which occurred on Jun. 19-20,2005 indicated that this precipitation course had two steam sources. The first one came from the Indian monsoon on the Indian Ocean, another one was the southeast trade wind coming from Australia. Analysis of different precipitation centres indicate that the precipitation in north of Fujian was related with south China quasi-stationary front, and meridional vertical profile of pseudo-equivalent potential temperature often appears like ＇Ω＇ pattern, the center of rainfall in Guangdong Heyuan belongs to convective precipitation, there is strong instability at low level. ARPS model is applied in this paper for numerical simulation of the precipitation process, the simulating results indicate that net precipitation is the main contribution to the frontal rain belt,and convective precipitation mainly comes from subgrid scale.