Abstract:The atmospheric water vapor conversion coefficient (K) is one of the key parameters affecting the precision of GNSS precipitable water vapor (GNSS-PWV) inversed from ground-based GNSS meteorology. Based on the data from 7 radiosonde stations in the Yangtze river delta, we calculate the K values from 2016 by numerical integration and use a multivariate linear fitting method to establish two new models. One model is elevation independent (Emardson-I), and the other one is elevation dependent (Emardson-H). Finally, we validate these two new models using K values from 2017. The experimental results show that the MAE and RMS of the Emardson-H forecasting model are 0.001 297 and 0.001 616, which are slightly better than the Emardson-I forecasting model (0.001 303 and 0.001 620 respectively). GNSS-PWV inversion precisions of the two models are equivalent, and their MAE and RMS are both better than 0.6 mm. Therefore, as for the GNSS-PWV inversion in Yangtze river delta, Emardson-I model has better efficiency advantages in real-time application of ground-based GNSS meteorology as there is no need to measure meteorological parameters and elevation.
HOU Xiaoling,ZHANG Wenwen,LI Li et al. Model Refinement of GNSS Atmospheric Water VaporConversion Coefficient in Yangtze River Delta[J]. jgg, 2021, 41(1): 17-20.