Prediction of Earth Rotation Parameters Using Local Approximation Techniques

M. S. Gribanova, E. A. Skurikhina

Transactions of IAA RAS, issue 54, 11–20 (2020)

DOI: 10.32876/ApplAstron.54.11-20

Keywords: local approximation, Earth rotation parameters, prediction, Earth rotation, Universal Time, coordinates of the Pole

Abstract

The work presents a study of the applicability of the local approximation technique for predicting the Earth rotation parameters. A brief overview of theoretical foundation of the local approximation method has been given. Various features of the algorithm for searching for the most optimal ones were tested. Based on these results, it was found that the most accurate and prompt prediction for the pole coordinates is obtained by iterative method on a reference interval of seven years and using the embedding dimension of about 340 days, for UT1 – UTC on the interval of three years and of 180 days. The results and their analysis based on their comparison with the data obtained from IERS, IAA RAS and EOPCPPP (Earth Orientation Parameters Combination of Prediction Pilot Project) are given. The accuracy of short-term prediction of up to 10 days for pole coordinates is close to the results accuracy of 2016–2018 IERS annual reports and the best methods from EOPCPPP (less than 3 mas). Up to 40 days is comparable in accuracy (better than 8 mas), while the accuracy of up to 90 days prediction is slightly worse. Medium and long-term predictions of the universal time are inferior to IERS forecast, but still provide good results. The main achievement was the RMS of the 1 day’s prediction for UT1 – UTC. According to the 2018–2019 data, it was 0.08 ms, which is the closest one to the accuracy of the IERS forecast.

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