2009年11月10日银川河东机场暴雪天气过程成因分析  

Analysis of Formation Reason on the Heavy Snow Process over Yinchuan Hedong Airport in 2009

作　　者：王海霞[1,2] 彭维耿 潘江勇[1,3] 梁希豪 

机构地区：[1]北京大学物理学院大气科学系,北京100871 [2]民航西北空中交通管理局宁夏分局,宁夏银川750009 [3]民航青岛空中交通管理站,山东青岛266108

出　　处：《安徽农业科学》2010年第21期11242-11245,共4页Journal of Anhui Agricultural Sciences

摘　　要：利用NCEP/NCAR逐日再分析资料和卫星云图资料,对2009年11月10～11日发生在银川河东机场的一次暴雪天气过程的发生、发展及演变特征进行了分析。结果表明,造成这次大雪的高空影响系统是500hPa高空槽、700及850hPa东移的高原低涡,地面影响系统是河套锢囚锋。西北地区上空持续的200hPa高空急流诱生了地面气旋。这次降雪过程中,西北地区东部的正涡度平流有利于低层低涡系统在东移过程中加强;从散度场分布来看,宁夏中北部200hPa为辐散,700、850hPa为辐合区,使得宁夏中北部地区上升运动持久而强烈。这次暴雪的水汽来源是低层3支气流,即高原低涡前部西南气流、来自四川盆地的偏南气流、来自华北的偏东气流。3支气流汇集于宁夏中北部使得大量水汽在该区域累积,给银川河东机场的这次暴雪天气提供了充沛的水汽条件。这次强降雪也存在较为明显的中小尺度特征,利用逐时的数字化卫星云图可以有效追踪中尺度云团的生消、移动。By using daily reanalysis data of NCEP/NCAR and satellite nephogram,the genesis,development and evolution feature of the heavy snow over Yinchuan Hedong Airport,which happened form Nov.10th to 11th,2009,were analyzed.Besides,further investigation was conducted on the circulation pattern,dynamic condition,water vapor source and structures of Mesoscale and Microscale of the heavy snow process.The results showed that,the main influencing systems of the typical precipitation process are the upper trough on 500 hPa,the moving eastward plateau lows on 700 hPa and 850 hPa,Hetao occluded front.The cyclone is emerged near the surface by the standing upper level jet on 200 hPa over the Northwest China.In the snowfall process,the positive vorticity advection in the Eastern Part of Northwest China took advantage of the eastward shifting cyclonic vortices development and maintain.According to the distribution of divergence fields,the main reason of this large-scale high precipitation weather is that the convergence of low level air flows（850 hPa to700 hPa）and the divergence of upper air flows（500 hPa）result in the strengthening and lasting of ascending motion over North and Middle Region in Ningxia.The water vapor source of this process were interacted by three air flows：the southwest airflow front of the Plateau vortex,the south airflow in Sichuan Basin,the east airflow in north china.A large number of water vapor accumulated in the region which three air flows interacted provided abundant moisture condition for this process.There are also obviously small-scale features on this process.When used by a digital satellite images can be effectively tracked in generation,dissipation and movement of the mesoscale cloud cluster.

关 键 词：暴雪 环流形势 水汽通量 银川河东机场 

分 类 号：S427[农业科学—植物保护]