两次不同类型降水中GPS水汽特征对比分析

通过对2008年7月14-15日的稳定性区域暴雨天气过程以及2008年6月25-26日的对流性强降水中GPS水汽体现出的特征进行分析,结果表明：GPS水汽在稳定性降水中对实际预报具有较好的指示性能,可以用来区分潮湿气团与干燥气团.当大气达到高湿条件,可降水量增长到顶点,即预示未来4-5h会有降水出现;当可降水量（PWV）≥50 mm的持续时间越长,实况降水量越大.在6月25-26日的雷暴降水中,受中小尺度天气系统影响,PWV曲线起伏剧烈,局地性特征明显,但与降水量级以及降水起止时间并无明显联系,对未来降水预报所起意义不大.

COMPARATIVE ANALYSIS OF GPS WATER VAPOR FEATURES OF TWO DIFFERENT PRECIPITATION TYPES

By analysis of the characteristics of GPS water vapor in the stability regional rainstorm process on 14-15 July 2008 and the convective heavy rainfall on 25-26 Jun 2008,the results show that GPS water vapor in the stability precipitation has a better indication of the actual forecast performance,which can be used to distinguish between the humid air mass and the drying air mass.When the atmosphere reaches the high humidity conditions,precipitable water growth to the vertex,then it means the next 4 to 5 hours there will be precipitation occurred,and the longer the precipitation ≥ 50 mm keeps,the greater the live precipitation.Because of the affection by the mesoscale systems,PWV curve on 25-26 June thunderstorm process is dramatically ups and downs,which shows obvious local characteristics,but there is no obvious link from the amount of precipitation and the end time.Also it＇s meaningless for further forecasting.