两种雷达风场对比和暴雨天气过程的风场特征分析

A comparison of two radars' wind fields and analysis of wind field characteristics in the processes of rainstorms

使用风廓线雷达VW产品和天气雷达VWP产品资料,采用数学统计和对比方法进行分析,结果表明:两部雷达风向误差大于20°的时间与空间分布区域,远大于风向误差小于或等于20°的时间与空间分布区域;8、9、11和12四个月的风向误差明显大于其它月份的风向误差;风速误差大于3m/s的区域主要出现在1 000m以上高度层,时间分布在1、2、3、10和12五个月;2月份3 000m的高度有一个风速误差大于7m/s的极值区;连续性降水造成的暴雨过程,主要是前期受低层暖平流区发展及暖区倒槽影响,后期受中高层冷平流及西风带低槽影响,中高层形成了西南急流区,急流区的低层呈波动状态;强降水造成的暴雨过程,主要特征是不同高度层多短波天气系统影响,中高层无西南急流,大气层结极不稳定。

Based on wind profiler radar VW products and weather radar VWP product data,using mathematical statistics and comparison methods,it shows that temporal and spatial distribution of two radarswind direction error that greater than 20° was far bigger than the temporal and spatial distribution of wind direction error that less than or equaled to 20°.The wind direction errors of August,September,November and December were obviously bigger than the wind direction errors of other months.The area of wind velocity error that bigger than 3m/s mainly appeared above 1000 meters height layer in January,February,March,October and December on temporal distribution.There was an extreme value area of wind velocity errors that bigger than 7m/s at the height of 3000 meters in February.Rainstorm processes caused by continuous rainfallmainly were infected by low layer warm advection zone development and inversion trough in warm zone in the early stage,middle or high layer cold advection and westerly trough in the later stage,forming southwest jet zone at middleor high layer and presenting the state of fluctuating at the low layer of the jet zone.Rainstorm processes caused by heavy-rainfallmainly were infected by many short-wave weather systems in different height layers,which has no southeast jet in middle or high layer with extremely unstable stratification.