Importance of Hydrostatic Delay Models in Deriving PWV from GPS Signal Delays

Abstract

Studies have shown that Precipitable Water Vapor (PWV) derived from the Global Positioning System (GPS) signal delays are useful in remote sensing applications like rainfall prediction. The GPS-PWV values are derived from the zenith Wet Delays (ZW D). The accuracy of the GPS-PWV values largely depends on the accuracy of ZW D values, which are depended on the accuracy of the Zenith Hydrostatic Delays (ZHD). In this paper, the effect of different ZHD models on the GPS-PWV values are analyzed using 1 year of data from 6 different GPS stations. It was found that the performance of the different ZHD models varies as per the location and an optimum ZHD model is suggested for the different regions.