Akademik Veri Yönetim Sistemi
2. International Congress of Engineering and Natural Sciences Studies, 7 - 09 Mayıs 2022, ss.186
In
space geodetic techniques such as GNSS and VLBI, error sources should be
eliminated to achieve precise positioning. Troposphere, one of the major error
sources, affects radio signals due to the dry air and water vapor in its
content. The signal delay because of the dry air can be obtained accurately
using empirical formulas. However, meteorological observations should be
considered to obtain signal delays because of the water vapor. Since obtaining
real-time meteorological parameters is onerous, troposphere models are used to
determine initial values of the parameters. Troposphere models can be produced
using radiosonde observations and Numerical Weather Model data. In this study,
two different troposphere model, which have been determined using ERA5’s
monthly averaged and daily datasets from 2015 to 2019 produced by European
Center for Medium-range Weather Forecasts, have been compared. Precision and
accuracy analyzes have been performed. In order to obtain accuracy of the
models, ERA5’s monthly averaged and daily products from 2020 have been used. According
to first results, it has been seen that precision of the model produced using
monthly averaged datasets is higher than daily’s. In addition, the highest
accuracies have been obtained with the model, which has been produced using
monthly averaged data, by validating monthly averaged datasets.