Characteristic differences in tropospheric delay between Nevada Geodetic Laboratory products and NWM ray-tracing

Abstract Numerical weather models (NWMs) are important data sources for space geodetic techniques. Additionally, the Global Navigation Satellite System (GNSS) provides many observations to continuously improve and enhance NWM. Existing comparative analysis experiments on NWM tropospheric GNSS delays suffer from being conducted in highly specific regions with limited spatial coverage; furthermore, length of time experiment is too short analyzing seasonal characteristics, insufficient number stations limits density, making it difficult obtain equipment-dependent distribution characteristics. After strict quality control preprocessing, we have calculated compared bias standard deviation delay approximately 7000 selected Nevada Geodetic Laboratory (NGL) 2020 European Centre Medium-Range Weather Forecasts (ECMWF) Reanalysis v5 (ERA5) hourly ray-traced same group stations. Characterizations time, space, linkage receivers antennas reveal positive biases 4 mm NGL zenith (ZTD) relative ZTD over most globe; moreover, there a amplitude reaching 6 bias, an antenna-related mean 1.6 delay. The obtained results can be used provide priori appropriate uncertainties; additionally, they applied assess suitability using NWMs real-time positioning solutions.