主办单位：中国气象局沈阳大气环境研究所
国际刊号：ISSN 1673-503X
国内刊号：CN 21-1531/P
气象与环境学报

气象与环境学报 ›› 2013, Vol. 29 ›› Issue (4): 1-10.doi:

• 论文 •    下一篇

湖北一次大暴雨过程两个强降水时段的诊断分析与数值模拟

高琦1 徐明 2 苟阿宁1   

  1. 1. 武汉中心气象台，湖北 武汉 430074；2. 中国气象局武汉暴雨研究所暴雨监测预警湖北省重点实验室，湖北 武汉 430074
  • 出版日期:2013-08-31 发布日期:2013-08-31

Diagnostic analysis of two heavy rainfall time periods in a torrential rain process and its numerical simulation in Hubei province

GAO Qi1 XU Ming2 GOU A-ning1   

  1. 1. Wuhan Central Meteorological Observatory, Wuhan 430074, China; 2. Hubei Key Laboratory for Heavy Rain Monitoring and Warning Research, Institute of Heavy Rain, China Meteorological Administration, Wuhan 430074, China
  • Online:2013-08-31 Published:2013-08-31

PDF (PC)

465

被引次数

5

摘要： 根据NCEP/NCAR再分析资料、常规观测和加密观测站资料以及FY-2C TBB资料，对2008年8月28—30日湖北暴雨过程两个强降水时段的大尺度环流背景和中尺度对流系统进行诊断分析。在此基础上，利用中尺度数值模式WRF的模拟结果对影响大暴雨过程两个强降水时段的中尺度对流系统和其他物理量场深入分析。结果表明：湖北大暴雨过程存在明显的两个降水增强阶段，它们发生与结束的时间近乎一致，并且第二阶段的强降水要比第一阶段强度更大；强降水第一阶段是由低涡切变与地面暖湿气流影响造成的，强降水第二阶段是由低涡切变、中低纬短波槽和地面冷空气共同影响造成的。两个强降水时段逐小时的降水与云团特征表明，雨团与云团的活动规律一致，其增幅均出现在晚上到凌晨时段。同时表明，β中尺度对流云团与此次暴雨过程关系密切；暖切变线自南向北影响第一时段降水增幅，西南涡中伸展出的冷切变线自西向东影响第二时段降水增幅，模式结果表明由冷切变线引起的第二时段降水增幅更大；两个强降水时段雨区上空均有较强的能量，强的水汽通量辐合贯穿整个降水过程，地面降水中心与其上空湿位涡大值中心有较好的对应关系。

关键词: 暴雨, 强降水, 云团

Abstract: Based on the daily NCEP/NCAR reanalysis data, the conventional and intensive observational data, the brightness temperature (TBB) from FY2C, the large-scale circulation background and mesoscale convective system of two heavy rainfall time periods in a torrential rain process on August 28-30, 2008 in Hubei province were diagnosed, and other physical quantities fields influencing this process were also analyzed by WRF model. The results indicate that there are two significantly precipitation enhancement time periods in this process, and both durations from the beginning to the end are same. Precipitation intensity is stronger in the second period than in the first one. The first heavy rainfall time period is formed by low vortex shear and surface warm moist airflow, while the second one is caused by low vortex shear, the middle and low level short wave trough and cold surface air. The hourly rainfall and cloud mass characteristics during the two periods suggest that motions of the rain mass and cloud mass are same, and enhancements of precipitation intensity appear at the night and early morning. It also suggests that the β mesoscale convective cloud cluster has a close relationship with the torrential rain process. The movement of warm shear line from south to north affects the rainfall enhancement in the first period, while that of cold shear line of southwest vortex from west to east affects the rainfall enhancement in the second. According to the model results, the increasing amplitude of rainfall in the second time is more significant. There is strong energy for two heavy rainfall periods over the study area. There exists the strong water vapor convergence in the whole process. The rainfall center at the surface has a good correlation with a large value center of the moist potential vorticity at upper level.

Key words: Torrential rain, Heavy rainfall, Cloud mass