本文选取2003-2005年太原多普勒雷达资料,对中小尺度的多普勒速度场特征进行了深入研究。从逆风区厚度、尺度、强度(速度切变)等方面作了详细地分析,并与相应的回波反射率因子Z及VIL(垂直累积液态水含量)值对照。结果表明:逆风区强度与反射率因子,逆风区厚度与VIL值,逆风区底层流场结构与强回波发展趋势密切相关。而且,绝大部分逆风区出现时间较降水开始时间有12h的提前。
This article carried out a study of the meso and small scale Doppler velocity fields character istic using the Doppler radar data in Taiyuan from 2003 to 2005. The Adverse Wind Regions(AWR)'s depth, dimensions, velocity shear etc. have been analyzed in detail, and contrasted with their corresponding radar reflectivity (Z) and Vertically Integrated Liquid Water (VIL). The results show that AWR's .strength and Z, AWR's thickness and VIL, AWR's bottom wind current structure and the developing trend of strong echoes are highly correlated. Most of AWR occurred ahead of the heave rainfall about one or two hours.