title: ITG: A New Global GNSS Tropospheric Correction Model.
abstract: Tropospheric correction models are receiving increasing attentions, as they play a crucial role in Global Navigation Satellite System (GNSS). Most commonly used models to date include the GPT2 series and the TropGrid2. In this study, we analyzed the advantages and disadvantages of existing models and developed a new model called the Improved Tropospheric Grid (ITG). ITG considers annual, semi-annual and diurnal variations, and includes multiple tropospheric parameters. The amplitude and initial phase of diurnal variation are estimated as a periodic function. ITG provides temperature, pressure, the weighted mean temperature (Tm) and Zenith Wet Delay (ZWD). We conducted a performance comparison among the proposed ITG model and previous ones, in terms of meteorological measurements from 698 observation stations, Zenith Total Delay (ZTD) products from 280 International GNSS Service (IGS) station and Tm from Global Geodetic Observing System (GGOS) products. Results indicate that ITG offers the best performance on the whole.
authors.affiliation: 1] School of Geodesy and Geomatics, Wuhan University, 129 Luoyu Road, Wuhan, 430079, China [2] Key Laboratory of Geospace Environment and Geodesy, Ministry of Education, Wuhan University, 129 Luoyu Road, Wuhan, 430079, China.
authors.forename: Yibin
authors.initials: Y
authors.lastname: Yao
authors.affiliation: School of Geodesy and Geomatics, Wuhan University, 129 Luoyu Road, Wuhan, 430079, China.
authors.forename: Chaoqian
authors.initials: C
authors.lastname: Xu
authors.affiliation: School of Geodesy and Geomatics, Wuhan University, 129 Luoyu Road, Wuhan, 430079, China.
authors.forename: Junbo
authors.initials: J
authors.lastname: Shi
authors.affiliation: School of Geodesy and Geomatics, Wuhan University, 129 Luoyu Road, Wuhan, 430079, China.
authors.forename: Na
authors.initials: N
authors.lastname: Cao
authors.affiliation: School of Geodesy and Geomatics, Wuhan University, 129 Luoyu Road, Wuhan, 430079, China.
authors.forename: Bao
authors.initials: B
authors.lastname: Zhang
authors.affiliation: School of Geodesy and Geomatics, Wuhan University, 129 Luoyu Road, Wuhan, 430079, China.
authors.forename: Junjian
authors.initials: J
authors.lastname: Yang