卫星资料变分分析“98·7”武汉—黄石地区特大暴雨中尺度锋面对流特征

Characteristics of the Convection in the Meso-Scale Front of the Serious Storm Rainfall over the Wuhan-Huangshi Region during July of 1998 through Variational Analysis by Satellite Data

采用卫星TOVS反演资料变分-滤波处理技术对1998年7月20～23日武汉-黄石特大暴雨成因进行了诊断分析,研究结果揭示了武汉-黄石特大暴雨过程呈类似中尺度对流复合体（Mesoscale Convective Complex,简称MCC）的中尺度锋面对流系统特征,提出了“98·7”特大暴雨过程存在显著的对流系统的复合偶极子特征,中尺度急流核的垂直复合体结构,中尺度锋面“湿舌”异常特征以及大尺度梅雨系统中的中尺度锋面的“冷楔”以及高层“暖盖”结构,上述综合特征描述了“98·7”特大暴雨过程类似MCC系统的三维中尺度锋面结构物理图像。采用卫星资料变分-滤波处理方案提出大尺度梅雨系统中突发性特大暴雨的中尺度物理模型,其诊断分析及研究结论对“98·7”异常特大暴雨的成因及其形成机理提供了新的研究思路。

The prognostic analysis on the cause of the serious storm rainfall over the Wuhan-Huangshi region during July 20-23 1998 is carried out through variational-filtering processing method by satellite TOVS retrieval data. The results showed that the process of the serious storm rainfall over the Wuhan-Huangshi region showed characteristics of convective system in the meso-scale front like MCC. It also indicated that the obvious characteristics of the multiple dipole of the convective system existed in the serious storm rainfall during the July of 1998, as well as the structure of the vertical multicell of the meso梥cale jet nucleus, the anomalous characteristics of the ' wet tongue', the 'cold wedge', 'warm mat' of the meso-scale front verge in large-scale Meiyu system and the phenomenon of the ' warm canopy' at higher level. The above synthesized feature showed that the physical image of the three-dimensional meso-scale structure of the meso-scale front is like the MCC system existing in the process of the serious storm rainfall during the July of 1998. The meso-scale physical model of the paroxysmal serious storm rainfall in the large-scale Meiyu system was suggested through variational-filtering processing method by satellite data. Its prognostic analysis and the study result provided a new study thinking for the cause and the mechanism of the anomalous serious storm rainfall during the July of 1998.