The study of calculating precipitable water vapor using GPS zenith tropospheric delay without meteorological data

With the data of GPS meteorology network in Wuhan region, the article discussed the study of directly calculating precipitable water vapor with GPS zenith tropospheric delay. In the comparison of radiosonde precipitable water vapor and GPS zenith tropospheric delay in Donghu of Wuhan, there is a good relativity and the correlative coefficient is 0.93. It deducted the model of directly calculating precipitable water vapor and proof-tested the model. The root mean square of GPS precipitable water vapor and radiosonde is 7.8mm and the correlative coefficient is 0.91 in the comparison between the precipitable water vapor of zenith tropospheric delay and radiosonde data. It was illuminated that the precipitable water vapor of zenith tropospheric delay can be considered as the reference of short-forecast of meteorology in the none meteorology data region.