Development of Global Tropospheric Empirical Correction Model with High Temporal Resolution

Abstract

The accuracy of global tropospheric empirical models depends on the model expression and the modeling data sources. Although the current temporal resolution of available models is usually one day, it is anticipated that this will be improved in the future. To achieve compatibility with future high temporal-resolution data sources, this study develops a new global tropospheric correction model, the Wuhan-University Global Tropospheric Empirical Model (WGTEM). Evaluation of WGTEM model expression determines that it has better precision than other models, and this is attributed to its ability to consider diurnal variations in meteorological parameters and the double-peak daily variation in air pressure, which are not concerned in other models. The external accuracy of the WGTEM was evaluated after modeling with the European Centre for Medium-range Weather Forecasts (ECMWF) ERA-Interim products, and results show its accuracy exceeds that of the current ITG model and its Zenith Tropospheric Delay (ZTD) performance is also superior.

Empirical Orthogonal Function Analysis and Modeling of Global Tropospheric Delay Spherical Harmonic Coefficients

“…Since the tropospheric delay exhibits a strong correlation with the altitude correction coefficient [14,16], the modeling effect is similar. In addition, with the limited length of the article, we only introduce the modeling process of the SH coefficients of the tropospheric delay in the SH_set products.…”

“…At present, the application of the traditional delay model is limited due to the lack of meteorological measurement equipment at many GNSS stations. In recent years, many scholars have developed a series of non-meteorological, parameter-based tropospheric delay empirical models via reanalysis of atmospheric datasets expressed as a function of the station location and time, such as the University of New Brunswick (UNB), European Geo-stationary Navigation Overlay System (EGNOS), Global Pressure and Temperature (GPT), IGGtrop, Global Tropospheric Model (GTrop) and Wuhan-University Global Tropospheric Empirical Model (WGTEM) models [7][8][9][10][11][12][13][14]. However, these models suffer from limited resolutions (a spatial resolution lower than 1 • and a temporal resolution lower than 6 h), which affects their performance.…”

Regression models for predicting daily IGS zenith tropospheric delays in West Africa: Implication for GNSS meteorology and positioning applications

“…This implies that pressure decreases with increasing altitude and vice versa, hence the possible reason the two are the potential cause of multicollinearity. Mathematically, pressure and altitude are related as follows (Liu et al, 2019;Simeonov et al, 2016;Sissenwine et al, 1962;Xu et al, 2020):…”