Inversion of the Distribution and Variation of ZWD over the Three Gorge Area with GPS Observation

With the continuous GPS monitoring data of the eight points of the Three Gorge area,the Zenith Total Delay over each points are extracted out.When processing the GPS data,we make use of the observation data of three IGS stations to minimize the correlation between ZTDs.After separating the zenith hydrostatic delay with the extrapolated surface pressure and Saastanmonien model,we get the zenith wet delay(ZWD).The ZWD sequential lines of all points are consistent.After analyzing the ZWD distribution figures of 8 hours in this area,some information of variation of the water vapor can be obtained.The feasibility of monitoring water vapor distribution and variation with ground-based GPS meteorology is discussed.Some conclusions and suggestions are obtained.