2009年山东一次特殊雨雪天气的云物理特征分析  

Analyses on Cloud Physical Characteristics in a Special Rain and Snow Processes of Shandong Province in 2009

作　　者：盛日锋[1] 马占山[2] 欧建军 王俊[1] 龚佃利[1] 姜鹏[4] 周毓荃[5] 

机构地区：[1]山东省人民政府人工影响天气办公室,山东济南250031 [2]中国气象局国家气象中心,北京100081 [3]上海海洋气象台,上海201300 [4]山东省气象台,山东济南250031 [5]中国气象科学研究院,北京100081

出　　处：《高原气象》2012年第6期1711-1720,共10页Plateau Meteorology

基　　金：山东省气象局重点课题"空中云水资源监测评估与可催化条件分析技术研究"(2012sdqxz07);山东省气象局课题(2008sdgxzl5)共同资助

摘　　要：利用探空、CloudSat卫星、山东自动气象站及NCEP再分析资料,对2009年11月11-12日山东西部大暴雪过程的天气形势、云物理特征及动力场结构特征进行了分析。结果表明:(1)700hPa切变线和西南急流是造成暴雪的直接影响系统,中低层偏南风急流与冷空气交汇形成较强的动力辐合和水汽辐合,有利于天气系统的发展和增强。(2)暴雪区上空水平能量锋区明显,垂直方向上等θse线密集且随高度向北显著倾斜,为暴雪的产生提供了重要的热力条件。(3)强降雪发生前,低层冷空气的南侵触发了暴雪系统的发展;暴雪强盛期,高层气旋性环流促使暴雪区中高层西南暖湿气流输送加强;暴雪后期,冷空气加强并逐渐控制了中低层,切断了暖湿气流的供应,导致降雪逐渐停止。(4)上升气流有助于水汽的输送和云滴、冰晶、雪晶粒子之间的碰并、淞附,冰水含量大值区与上升速度大值区相一致,冰晶数浓度中心对应着上升运动顶部。高层冰晶下落过程中经过凝华、结淞及碰连增长在低层形成数浓度较低的大冰相粒子,为降水发展提供了有利条件。(5)结合CloudSat卫星资料、NCEP再分析资料及探空秒数据,分析了一定动力条件下暴雪云系的物理过程和垂直演变特征。Based on the sounding data,CloudSat data,automatic observational data and NCEP reanalysis data,the microphysical process,weather situation and dynamic field of blizzard in the western part of Shandong on 11-12November 2009were analyzed.The major conclusions are as follow：（1）The shear line and southwest jet on 700hPa played important roles in blizzard.The intersection of low-level southerly wind jet and cold air formed strong convergence and moisture convergence,which was conductive to the development and enhancement of the weather system.（2）The intersection of cold and warm air over snow area formed apparent energy front in horizontal and vertical directions.In the vertical direction,θsecontour was intensive and a significant northward with height,which produced thermal conditions for Blizzard.（3） Before the snowfall,the invasion of cold air in low level triggered the circulation development of snow.During the severe snow period,the appearance of cyclonic circulation on upper level enhanced transportation of southwest warm air.In the late of snowfall,the cold air strengthened and dominate in low level,which cut off the supply of warm air,so snow gradually stopped.（4）Comprehensive analysis revealed cloud microphysical process and vertical evolution under some dynamic conditions using CloudSat,NCEP reanalysis data and L-band radar sounding data,Updraft can help the delivery of water vapor.At the same time,cloud droplet,ice crystal particle,snow crystal particle were better mixed,coagulated or condensated with each other.Big value zone of ice water content were consistent with the one of vertical velocity,and the centre of number concentration of ice crystal located at the top of upward motion.L-band radar sounding data reflected the vertical evolution of heavy snow cloud under a certain dynamic condition.

关 键 词：暴雪 CLOUDSAT卫星 云物理过程 动力场特征 

分 类 号：P426.51[天文地球—大气科学及气象学]