利用雷达资料反演方法对北京地区一次强对流天气过程的分析  

Analysis of a Severe Convective Storm Event in Beijing Using the Thermodynamical Retrieval Method of Radar Data

作　　者：樊利强[1] 王迎春[1] 陈明轩[1] 

机构地区：[1]中国气象局北京城市气象研究所,北京100089

出　　处：《气象》2009年第11期9-16,I0001,共9页Meteorological Monthly

基　　金：北京科委计划项目(Z2006279040191);科技部行业(气象)专项项目(GYHY200706004)

摘　　要：利用多普勒雷达变分分析系统(VDRAS),对2006年8月1日傍晚北京城区出现的一次强对流天气过程(伴有冰雹、大风及强降水)的三维风场、温度场进行了初步分析。结果表明:(1)初始对流生成于北京西北部山区的河北省境内,系统过山移进北京城区时,受局地的动力及热力条件作用,迅速组织并强烈发展,形成带状的MCS即飑线;(2)在飑线生成之前,北京城区及东南部边界层低层存在较强的东风气流,并迅速扩展向西北方向延伸,与过山的西北偏北气流形成强的边界层辐合线。该近地面辐合线是飑线生成的主要触发机制,而边界层低层东风的加强和减弱以及北进和南退对辐合线的维持、飑线的生成、发展和减弱都起着重要的作用;(3)在边界层辐合线的作用下,不断有新生对流系统发展;(4)对流系统在整个发展过程中呈明显的带状分布特征,是一次典型的飑线过程,并伴有明显的阵风锋。A preliminary diagnosis on a severe convective storm（with heavy rainfall,hail and strong wind）attacking Beijing urban zone on 1 August 2006,by using the radar data retrieval method of low-level wind,temperature and relative humidity based on the Variational Doppler Radar Analysis System（VDRAS）is shown in this study with the results as follows.（1）The convective storm initiated in Hebei Province adjacent to the northwest mountainous area of Beijing,then it was organized and strengthened quickly while it moved into Beijing area under the condition of local thermodynamical forcing,and finally developed into a squall line.（2）A strong easterly flow persisted at low levels in Beijing urban zone and southeast of great Beijing before the squall line initiated.The flow extended northwestward quickly and collided with across mountain northwesterly winds to trigger a boundary layer convergence line.The latter was the primary triggering factor of the squall line initiation.The intensification,weakening and north-south movement of the easterly flow at low levels had a distinct effect on initiation,enhancement and dissipation of the squall line,as well as persistence of the convergence line.（3）New storm cells initiated continually under the effect of the convergence line.（4）The intense convective storm went with a strong gust front.

关 键 词：强对流天气 雷达变分分析系统 飑线 辐合线 阵风锋 

分 类 号：P448[天文地球—大气科学及气象学] P631.44