Monitoring of tidal deformations of the Earth’s crust at different latitudes using GNSS (Global Navigation Satellite Systems)
DOI:
https://doi.org/10.17308/geology/1609-0691/2026/1/96-106Keywords:
solid Earth tides, GNSS monitoring, PPP positioning, Earth surface deformations, latitudinal dependence, Earth’s crust, ocean tidesAbstract
Introduction: the paper focuses on refining methodological approaches to monitoring vertical displacements of the Earth’s crust caused by lunar–solar gravitational interaction using global navigation satellite system (GNSS) stations located at different latitudes for the period from 7 February to 6 April 2019.
Methods: for the first time in Russia, a systematic comparison of the amplitudes of the tidal harmonics M2, S2, K1, and O1 at six stations of different latitudes has been carried out using a unified Precise Point Positioning methodology in kinematic mode and the FES2022b ocean loading model. A sequential multistage digital filtering procedure was applied to reduce high‑frequency noise. Using spectral analysis based on the fast Fourier transform algorithm, the dominant tidal components M2, S2, O1, and K1 were identified from the resulting time series of vertical displacements.
Results and discussion: the measured periods agree with the theoretical values within ±0.3% for all main harmonics. The signal‑to‑noise ratio for the harmonic amplitudes exceeds 4 at all stations, which confirms the reliability of the extracted components. The close agreement between theoretical and observed periods indicates that solid Earth tidal signals can be reliably extracted from GNSS observations at stations located at different geographic latitudes, confirming the ability to resolve vertical variations of the Earth’s surface. It is shown that local GNSS observations at different latitudes can improve the quality of studies of solid Earth tides and vertical displacements of the Earth’s crust.
Conclusions: the obtained results substantiate the applicability of global GNSS networks for establishing geodynamic monitoring systems that complement gravimetric measurements.
Downloads
References
1. Vincente R. The Tides and the Planet Earth. Oxford, Pergamon Press, 1978, 256 p.
2. Levin Dzh. Prilivy Zemli [Earth's tides]. Fizika prepodavatelja − Physics Teacher, 1982, vol. 20, no. 9, pp. 588–595 (In Russ.)
3. Molodenskii M. S. Vvedenie v teoriyu prilivnykh deformatsii Zemli [Introduction to the theory of tidal deformations of the Earth]. Moscow publ., 1970, 200 p. (In Russ.)
4. Pariyskii N. N. Zemnye prilivy i vnutrennee stroenie Zemli [Earth tides and internal structure of the Earth]. Moscow, Nauka publ., 1976, 232 p. (In Russ.)
5. Wahr J. M. Body tides on an elliptical, rotating, elastic and oceanless Earth. Geophysical Journal International, 1981, vol. 64, no. 3, pp. 677–703.
6. Gudkova T. V. Prilivnye vzaimodeistviya v solnechnoi sisteme [Tidal interactions in the Solar System]. Zemlya i Vselennaya – Earth and the Universe, 2024, no. 1, pp. 48–58 (In Russ.)
7. Melchior P. The Tides of the Planet Earth. 2nd ed. Oxford, Pergamon Press, 1983, 641 p.
8. Zumberge J. F., Heflin M. B., Jefferson D. C., Watkins M. M., Webb F. H. Precise point positioning for the efficient and robust analysis of GPS data from large networks. Journal of Geophysical Research, 1997, vol. 102, no. B3, pp. 5005–5017.
9. Takasu T. RTKLIB: An open-source program package for GNSS positioning. Ver. 2.4.2 Manual. 2013. Available at: http://www.rtklib.com/
10. Takasu T., Yasuda A. Development of the low-cost RTK-GPS receiver with an open-source program package RTKLIB. International Symposium on GPS/GNSS, Jeju, Korea, 2009.
11. Kouba J. A guide to using International GNSS Service (IGS) products. Ottawa, Natural Resources Canada, Geodetic Survey Division, 2009, 72 p.
12. Ilyukhin A. A., Koneshov V. N. K vyboru metoda obrabotki GPS izmerenii geodinamicheskikh peremeshchenii tochki zemnoi poverkhnosti v vysokochastotnom diapazone [On the choice of a method for processing GPS measurements of geodynamic point displacements in the high-frequency band]. Seismicheskie pribory – Seismic Instruments, 2016, vol. 52, no. 2, pp. 39–45 (In Russ.)
13. Kierulf H. P., Plag M., Plag H.-P. Comparison of GPS analysis strategies for high-accuracy vertical land motion. Physics and Chemistry of the Earth, 2008, vol. 33, no. 3–4, pp. 194–204.
14. Penna N. T., Clarke P. J., Bos M. S., Baker T. F. Ocean tide loading displacements in Western Europe: Part 1. Validation of kinematic GPS estimates. Journal of Geophysical Research: Solid Earth, 2015, vol. 120, no. 9, pp. 6523–6539.
15. International Earth Rotation and Reference Systems Service (IERS). International Earth Tide Service (IETS/IGETS). Available at: http://igets.u-strasbg.fr/
16. Lyard F. H., Allain D. J., Cancet M., Carrère L., Picot N. FES2014 global ocean tide atlas: design and performance. Ocean Science, 2021, vol. 17, no. 3, pp. 615–649.
17. Scherneck H.-G. A parametrized solid earth tide model and ocean tide loading effects for global geodetic baseline measurements. Geophysical Journal International, 1991, vol. 106, no. 3, pp. 677–694.
18. Bos M. S., Scherneck H.-G. Free Ocean Tide Loading Provider. Onsala Space Observatory, 2013.
19. Petit G., Luzum B. (Eds.). IERS Conventions (2010). IERS Technical Note No. 36. Frankfurt am Main, Verlag des Bundesamts für Kartographie und Geodäsie, 2010, 179 p.
