首先分析了多普勒雷达垂直累积液态含水量(VIL)产品的不足之处,并在此基础上提出了直接将雷达反射因子作空间积分的算法;然后综合利用重新计算的VIL、VIL密度和不同高度的反射率密度(VIZ),来判断和识别强对流天气;最后通过对发生在江西境内的1次弱降雹过程的分析,在日常临近预报流程的基础上,着重分析了VIZ、VIL和VIL密度等物理量的时间变化特点。分析结果表明,这些物理量除了可以准确判断出有冰雹发生外,还可以根据其时间变化大致估算出地面降雹时间。
In this paper, the shortage of VIL product on Doppler radar is expatiated,and a new algorithm with spatial integration of reflectivity value is proposed. By the combined analysis of the recalculated VIL, VIL density and reflectivity density (VIZ) at different heights, the convective weather can be recognized and distinguished. Based on the routine nowcasting flow, a weak hail event in Jiangxi is analyzed with emphasis on the change trend of those parameters as VIZ, VIL and VIL density. The result shows that not only the hail can be recognized, but also its falling time can be estimated by using those parameters.