基于湖南CORS网的PWV时空变化分析及其在暴雨落区预报中的应用

针对2017-05-22~05-23湖南地区的一次暴雨过程，结合气温、气压等大气热动力条件，分析此次降雨过程的大气可降水量(precipitable water vapor，PWV)时空分布及其动态变化特征。研究表明，在水汽条件充足的情况下，降雨的形成需要强烈的水汽辐合上升作用，可以结合热动力条件来预判降水时间和强度；PWV与实际降雨量平面分布图的对比分析表明，PWV高值区和实际降雨落区基本重合，PWV时空变化分析对预测暴雨落区有一定的指示意义。

Analysis of PWV Spatiotemporal Variation and Its Application to Forecast the Falling Area of Rainstorm Based on Hunan CORS

Atmospheric precipitable water vapor (PWV) over the station can be estimated using ground-based GPS technology. The variation characteristics of PWV have very good indicators to the predict precipitation time and falling area. Along with the atmospheric thermodynamic conditions such as temperature and pressure, we analyze the variation characteristics of timeseries and plane dynamic distribution of PWV during the rainstorm that occurred May 22-23, 2017 in Hunan province. The results show that the formation of precipitation requires strong convergence ascending of water vapor. The precipitation time and intensity can be predicted by combining thermal dynamic conditions in the case of sufficient water vapor conditions. The contrastive analysis of plane distribution maps of PWV and actual precipitation shows that the high value region of PWV basically coincides with the falling area of the rainstorm. It means that GPS-PWV has certain indicating significance to forecast the falling area of the rainstorm.