【摘要】 对大连2003—2005年降水天气过程的多普勒雷达速度场资料进行统计和分析,得到几种雷达回波速度场特征对降水变化及人工增雨作业的影响,总结了雷达回波速度场的零速度线呈"S"型、"弓"型和速度不对称型几种常见的分布特征对人工增雨潜力分析和作业条件判别的辅助判据指标。并结合EVAD技术和变分法定量计算大气平均散度和垂直速度方法,对大连2006年夏季一次人工增雨作业过程进行了分析,得到了回波速度场特征与计算的平均散度和垂直速度的较好的配合关系。更多还原

【Abstract】 By statistical analysis of Doppler radar velocity field data of rainfall processes from June 2003 to October 2005 at Dalian district,the indications of several familiar echo velocity characters of the cloud systems developing into rainfall were obtained.Several criterions were concluded for analyzing the precipitation potential region and the opportunity for precipitation enhancement operation while radar echo showed "s" or bow shape.Combined with EVAD technique and variation to calculate average divergence and vertical velocity,the practical validation showed good results in a precipitation enhancement operation at Dalian district in summer 2006,in that case,the PPI velocity field showed "s" shape and matched well to the average divergence and vertical velocity.更多还原