暴雪过程中多普勒雷达速度产品分析  

The analysis on Doppler velocity product of snowstorm occurred in Nanjing in January of 2008

作　　者：蒋义芳[1] 吴海英[1] 王卫芳[1] 刘安宁[1] 王啸华[1] 

机构地区：[1]江苏省气象台,南京210008

出　　处：《气象科学》2010年第4期542-547,共6页Journal of the Meteorological Sciences

基　　金：江苏省气象科研开放基金项目(200910)

摘　　要：利用多普勒天气雷达提供的强度、径向速度、风廓线产品及衍生产品对2008年1月25—29日南京持续性暴雪天气回波的演变过程以及回波不同阶段风场垂直结构及其动力条件的变化进行了分析,结果表明:存在持续的低空东北气流以及风向垂直切变的风场结构是这次暴雪天气产生的主要环境特征,暖平流和中层强西南急流有利于产生持续的暴雪,低层辐合、高层辐散及较大的垂直上升运动为暴雪的产生提供了动力条件;任意高度出现西北风,可以作为强降雪将会趋于减弱的临近预报指标。Based on the data of reflectivity factor and radial velocity and wind profile and derivative product provided by Doppler radar,the evolution and the characteristics of vertical wind structure of a snowstorm process occurred in Nanjing on January 25 to 29,2008 is analyzed.The result shows that northeast wind flow at low level lasting for a long time,combined with vertical wind shear,is the main environment feature of this snowstorm process.Strong convergence and warm advection at low level as well as strong southwest jet stream at middle level are the important factors of producing lasting snowstorm.The low-level convergence and high-level divergence provide dynamic conditions for lasting snowstorm.The occurrence of the northwest wind at any altitude is a good index of nowcasting that the snowstorm will tend to weaken.

关 键 词：暴雪 风向垂直切变 暖平流 

分 类 号：P426.634[天文地球—大气科学及气象学]