河南省层状降水云系中尺度结构的数值模拟  

Numerical Simulation on the Mesoscale Structure and Organization of a Stratiform Cloud System in Henan Province

作　　者：翟菁[1] 周毓荃 杜秉玉[1] 

机构地区：[1]南京信息工程大学应用气象学院,江苏南京210044 [2]国家气象中心,北京100081

出　　处：《南京气象学院学报》2007年第1期34-42,共9页Journal of Nanjing Institute of Meteorology

基　　金：国家"十五"攻关资助项目(2001BA610A06)

摘　　要：利用非静力中尺度数值模式MM5(V3.5),结合实况资料,对2002年4月4—5日河南春季一次层状降水云系的中尺度结构进行了模拟分析,并与观测资料进行了对比研究。结果显示,4月4日08时—5日20时之间,850 hPa低涡与中高空低槽相配置,形成大范围具有非均匀性结构特征的云系。模式模拟出降水中雨核的产生、发展、消散,雨核所在处云系有水平尺度在几十至100 km之间的柱状结构,对应云系组合为:高层主要由冰晶组成,中层由冰相粒子和液水混合组成,低层为液水层,并伴有强烈的上升气流,雪和霰对雨水形成的贡献较大。模式还揭示了850 hPa中-β尺度低涡和水汽输送对雨核起到关键性作用。The mesoscale structure and organization of a stratiform cloud precipitation system occurring during April 4 to 5,2002, in Henan province are simulated by using nonhydrostatic mesoscale numerical model MM5 （ v3.5 ）, and analysed by contrasting the simulated results with the observations. The results show that there were a low vortex at 850 hPa and a low trough at 500 hPa and 700 hPa, and a cloud system formed and developed from 0800BST April 4 to 2000BST April 5, and displayed inhomogeneous structual character. The simulation results show the rain cores＇ appearing, growing, and disappearing within the cloud bodies of columned structure on 10--100 km horizontal scale in the cloud system, where ice crystals form in the upper layer, ice phase particles and supercooled water coexist in the middle layer, and liquid water as well as strongest ascending airflow dominates in the low layer. Snow and graupel contribute most to rain＇ s forming. The simulated results also reveal the key impacts of the meso-β low vortex at 850 hPa and the vapor transportation on the rain cores.

关 键 词：中尺度模式MM5 低涡 雨核 中尺度结构 

分 类 号：P426.611[天文地球—大气科学及气象学]