多普勒天气雷达风场产品在螺旋度计算中的应用  

APPLICATION OF DOPPLER WEATHER RADAR WIND PRODUCTS IN HELICITY COMPUTATION

作　　者：徐芬[1] 夏文梅[1] 胡志群[2] 胡胜[3] 宋娟[1] 

机构地区：[1]江苏省气象科学研究所,南京210008 [2]南京信息工程大学,南京210044 [3]广州中心气象台,广州510080

出　　处：《气象科学》2007年第5期495-501,共7页Journal of the Meteorological Sciences

基　　金：国家自然科学基金项目(编号:40475017);江苏省科技厅项目(编号:BS2003054)共同资助

摘　　要：本文介绍了一种利用新一代天气雷达风场产品VWP计算螺旋度的方法,通过对两次大面积降水个例的螺旋度诊断分析发现,利用VWP风场产品计算的螺旋度具有较高的时间分辨率,大面积降水的螺旋度变化趋势与降水变化趋势比较吻合,螺旋度变化一般提前于降水变化,有2—3 h的提前预报量;螺旋度数值的大小与降水量的大小一般没有明显线性关系;螺旋度可以作为观测雷达站上空风场随高度变化的一个敏感因子;利用VWP风场产品来作为计算螺旋度的风场资料是可行的,比起其它风场资料更适于短时(临近)预报的业务化工作。In this article, VWP computed in helicity as wind data is introduced. Using two diagnostic analysis of large area rain with helicity, we found that helicity computed by VWP has better time resolution. The variations in helicity is almost consistent with the variations of rainfall, and vari.ations in helicity is commonly ahead of the variations of rainfall by 2-3 hours. There is no distinctive linear relationship between helicity value and rainfall amount. Helicity is a good indicator for variations of wind field with altitude. VWP as the wind data for computing helicity is feasible and is more suitable for nowcasting work compared with other wind data.

关 键 词：多普勒雷达 VWP产品 螺旋度 

分 类 号：P456.9[天文地球—大气科学及气象学]