层状云人工增雨宏观判据在MICAPS平台上的演示与应用

针对地市级普遍缺乏可业务应用的人工增雨潜力实时分析及预测系统的情况,以常规探空资料和T213数值预报产品为基础资料,开发了几种人工增雨宏观诊断场,并实现了这些诊断场的定时自动处理和在MICAPS平台上的实时分析显示.其中,冰面过饱和度可诊断“冰水转化区”的垂直分布,进而为确定合适的播撒高度提供判据.T-Td垂直分布可反映准饱和湿层伸展的高度和厚度,其顶部为合适的播撒高度;特征温度层高度可提供＂播云温度窗区＂的高度和厚度,也可为进一步确定播撒高度提供判据.几种方法综合应用可确定最佳播撒高度.增雨潜力系数与降水的演变趋势很一致,可为选择合适的作业时机提供参考.以一次典型过程为例,对上述方法做了试用.为了定量确定人工增雨潜力的大小,综合考虑了各种物理量（要素）场对降水的贡献以及降水预报对宏观增雨潜力的指示意义,应用多因子权重集成法,制作人工增雨潜力等级预报,并用2004年2～5月7次层状云降水过程进行实例应用检验,证明具有一定效果.

Display on MICAPS Platform and Application of Macro-Criterions for Rain Enhancement in Stratiform Clouds

Based on observation data and NWP products,some diagnosis fields for rain enhancement were worked out and the real-time automatic display on MICAPS platform was realized.The supersaturation with respect to ice can be used to diagnose the vertical distribution of ice-water conversion area,then determine the seeding height.The vertical disposition of T-T_d can show the altitude and depth of the quasi-saturation layer,the top of which was the suitable seeding position.The height of the characteristic temperature layer can be used to determine the altitude and thickness of "seeding temperature window," a seeding position criterion.The optimal seeding altitude can be determined by synthesizing above methods.The trend of rainfall enhancement potential coefficient was identical with that of rainfall,which can provide reference for choosing appropriate seeding time.The above-mentioned methods were applied during a typical rain case. In the weighted integrating manner,several environmental physical fields and rainfall forecast were synthesized,and the graded forecast of rain enhancement potential was made.The verification was conducted by seven stratiform-cloud rain cases occurred from February to May 2004.The results show that the method is encouraging.