ESTIMATION OF PRECIPITABLE WATER VAPOR BASED ON
INTERPOLATED PRESSURE DATA
1)College of Geomatics and Geoinformation, Guilin University of Technology, Guilin 541004
2)Guangxi Key Laboratory of Spatial Information and Geomatics, Guilin 541004
Abstract 〗The meteorological data are obtained by pressure interpolation for the estimation of GPS precipitable water vapor (PWV) due to the lack of meteorological parameters at GPS sites. The pressure interpolation formula based on segmented height difference is derived by analyzing the relationship between the interpolated pressure at the GPS sites and the pressure at the nearby radiosonde (RS) stations, and the relationship between the interpolated pressure of the GPS sites and the height difference between the IGS stations and the nearby radiosonde stations using the standard atmosphere (SA) model. The new pressure interpolation formula has the same accuracy as the SA model, and the former is simple when the height difference is less than 100 m. GPS PWV is derived from the new pressure interpolation formula, Saastamoinen zenith hydrostatic delay (ZHD) model and the local weighted mean temperature of the atmosphere (Tm). By comparing with RS PWV, the results show that the new pressure interpolation model can be used to calculate GPS PWV with no meteorological data at GPS stations which the RMS error between GPS PWV obtained from the pressure interpolation formula based on segmented height difference and RS PWV is 13 mm.
