Abstract:To analyze the accuracy of GNSS water vapor inversion performed by surface temperature and pressure products in China based on the latest MERRA-2 reanalysis data released by NASA, we combine the measured temperature and pressure data of 609 surface weather stations in China, 48 GNSS stations and co-location radiosonde stations. We evaluate MERRA-2 temperature and pressure products and their accuracy in GNSS PWV inversion. The results show that: 1) The annual average bias of MERRA-2 pressure and temperature data are -0.01 hPa and 0.38 K, respectively, and the annual average RMSE are 1.08 hPa and 2.66 K, respectively. The MERRA-2 reanalysis temperature and pressure products have high accuracy in China. 2) The temperature and pressure products of MERRA-2 reanalysis data show a negative deviation in most regions of China, and the order of accuracy from high to low is the southern region, the northern region, the northwest region and the Qinghai-Tibet Plateau region. 3) Compared with the PWV measured at the co-location sites, the average RMSE of GNSS PWV derived from MERRA-2 temperature and pressure products is 2.16 mm, and can better reflect the daily variation of PWV. Therefore, MERRA-2 surface temperature and pressure products have important applications in meteorological research and GNSS water vapor monitoring in China.
CUI Lei,XU Jiao,HUANG Ling et al. Accuracy Analysis of Chinese Mainland GNSS Water Vapor Inversion Using MERRA-2 Surface Temperature and Pressure Data[J]. jgg, 2023, 43(2): 186-190.