An ERA5 tropospheric parameters-augmented approach for improving GNSS precise point positioning  

作　　者：Liangke Huang Feifan Liu Lijie Guo Guiwen Lan Lv Zhou Cheng Wang Lilong Liu 

机构地区：[1]College of Geomatics and Geoinformation,Guilin University of Technology,Guilin 541006,China [2]Wuhan Changjiang Waterway Rescue and Salvage Bure,Wuhan 430014,China [3]Guangxi Institute of Natural Resources Survey and Monitoring,Nanning,530023,China

出　　处：《Geodesy and Geodynamics》2023年第5期467-476,共10页大地测量与地球动力学（英文版）

基　　金：funded by the National Natural Foundation of China (Grant No.41704027;41864002);the Guangxi Natural Science Foundation of China (2020GXNSFBA297145);the “Ba Gui Scholars” program of the provincial government of Guangxi;the Innovation Project of Guangxi Graduate Education (Grant No. YCSW20211209)

摘　　要：Precise Point Positioning(PPP) technology has developed into a potent instrument for geodetic positioning, ionospheric modeling, tropospheric atmospheric parameter detection, and seismic monitoring.As atmospheric reanalysis data products’ accuracy and spatiotemporal resolution have improved recently, it has become important to apply these products to obtain high-accuracy tropospheric delay parameters, like zenith tropospheric delay(ZTD) and tropospheric horizontal gradient. These tropospheric delay parameters can be applied to PPP to reduce the convergence time and to increase the accuracy in the vertical direction of the position. The European Centre for Medium-Range Weather Forecasts Reanalysis 5(ERA5) atmospheric reanalysis data is the latest product with a high spatiotemporal resolution released by the European Center for Medium-Range Weather Forecasts(ECMWF). Only a few researches have evaluated the application of ERA5 data to Global Navigation Satellite System(GNSS)PPP. Therefore, this study compared and validated the ZTD products derived from ERA5 data using ZTD values provided by 290 global International GNSS Service(IGS) stations for 2016-2017. The results indicated a stable performance for ZTD, with annual average bias and RMS values of 0.23 cm and 1.09 cm,respectively. Further, GNSS observations for one week in each of the four seasons(spring: DOY 92-98;summer: DOY 199-205;autumn: DOY 275-281;and winter: DOY 22-28) from 34 multi-GNSS experiments(MGEX) stations distributed globally in 2016 were considered to evaluate the performance of ERA5-derived tropospheric delay products in GNSS PPP. The performance of ERA5-enhanced PPP was compared with that of the two standard GNSS PPP schemes(without estimated tropospheric horizontal gradient and with estimated tropospheric horizontal gradient). The results demonstrated that ERA5-enhanced GNSS PPP showed no significant improvement in the convergence times in both the Eastern(E) and Northern(N) directions, while the average convergence time over four weeks in t

关 键 词：Precise point positioning ERA5 atmospheric reanalysis data Multi-GNSS Tropospheric delay 

分 类 号：P228.4[天文地球—大地测量学与测量工程]