【摘要】 应用NCEP再分析资料及常规地面观测资料,对2005年7月21-24日河南省大暴雨过程中准地转Q矢量作了诊断分析,结果发现:在对流层低层850 hPa等压面上,Q矢量散度的负值区与暴雨落区有着较好的对应关系;Q矢量散度场在垂直方向上出现低层辐合、高层辐散配置时,利于暴雨的产生,暴雨区位于Q矢量辐合中心下方,降水的强弱与Q矢量的低层辐合及高层辐散强弱变化一致。Q矢量的y分量能较好地反映出锋生、锋消的作用,并能指示6-12 h后的暴雨落区。更多还原

【Abstract】 By using NCEP reanalysis data and some routine observation data,the quasi-geostrophic Q-vector of the regional heavy rainfall process in Henan province from 21 to 24 July 2005 was diagnosed.The results indicated that the negative area of the divergence field of the Q-vector was correlated well to the heavy rainfall regions at the 850hPa.It was easier for the heavy rainfall occurrence when the divergence field of the Q-vector appeared convergence at the low level and divergence at the high level on its vertical direction.The heavy rainfall regions were located under the convergence center of the Q-vector.The precipitation intensity coincided with the strength of convergence at the low level and divergence at the high level.The Q-vector y component reflected well the function of frontogenesis and frontolysis,and it indicated the location of the heavy rainfall from 6 to 12 hours in the future.更多还原