GPS PWV在大气降雨及洪水预报中的应用

Regional Precipitation and Flood Forecasting Using GPS Precipitable Water Vapor

针对预见期短已成为水文预报发挥更大效益的主要障碍的问题,基于GPS遥感大气水汽原理,以美国地基GPS监测网为例,验证了地基GPS探测PWV的精度,探讨了利用区域GPS网探测可降水量时最佳网外辅助站数目。结果表明,GPS方法可在降雨发生数小时前提供时空分辨率远高于传统探空探测方法的可降水量序列,且完全满足区域降雨与洪水预报的精度要求;利用区域GPS网监测大气水汽时加入3个网外辅助站为最佳选择。

The short flood forecast period can not meet the growing needs in the operational practice of flood preven- tion and disaster reduction. Based on the principle of GPS remote sensing precipitable water vapor （PWV）, the detection accuracy of PWV with foundation GPS is verified by taking foundation GPS monitoring network of America for an exam- ple. And then the optimal number of auxiliary station is discussed by using regional GPS network for detection PWV. The results show that the GPS PWV series obtained hours before rainfall has much higher spatial and temporal resolution than that of the traditional method, which can completely meet the requirements of regional precipitation and flood forecasting; three auxiliary stations is the best choice for detection PWV with regional GPS network.