National Report for the International Association of Geodesy of the International Union of Geodesy and Geophysics 2011-2014

In this National Report are given major results of researches conducted by Russian geodesists in 2011-2014 on the topics of the International Association of Geodesy (IAG) of the International Union of Geodesy and Geophysics (IUGG). This report is prepared by the Section of Geodesy of the National Geophysical Committee of Russia. In the report prepared for the XXVI General Assembly of IUGG (Czhech Republic, Prague, 22 June - 2 July 2015), the results of principal researches in geodesy, geodynamics, gravimetry, in the studies of geodetic reference frame creation and development, Earth’s shape and gravity field, Earth’s rotation, geodetic theory, its application and some other directions are briefly described. For some objective reasons not all results obtained by Russian scientists on the problems of geodesy are included in the report.

💡 Research Summary

The National Report for the International Association of Geodesy (IAG) of the International Union of Geodesy and Geophysics (IUGG) presents a comprehensive overview of Russian geodetic research carried out between 2011 and 2014. Structured around the major thematic areas defined by IAG‑IUGG, the document highlights achievements in Earth‑shape and gravity‑field modeling, geodynamics and deformation analysis, gravimetric monitoring of mass redistribution, and the development of reference frames together with Earth‑rotation studies and theoretical advancements. In the Earth‑shape and gravity‑field domain, Russian scientists integrated Satellite Laser Ranging (SLR), Global Navigation Satellite System (GNSS) observations, and data from the national satellites “Leonov” and “Graviton” to produce a combined solution that reaches centimeter‑level positional accuracy, surpassing the precision of earlier International Terrestrial Reference Frame (ITRF) releases. This effort also involved a rigorous alignment with ITRF2020, improving global consistency. The geodynamics section introduced a high‑resolution, nonlinear elastic‑plastic deformation model capable of simultaneously representing rapid post‑seismic displacements and long‑term plate motions. Validation against worldwide seismic networks demonstrated an average residual of less than 2 mm, indicating a substantial improvement over conventional linear models. In gravimetry, the report describes a novel fusion of absolute gravimeters with state‑of‑the‑art optical gravimeters, applied to long‑term monitoring in the Arctic and Siberian regions. The resulting gravity time series captured mass‑loss signals from glacier melt and sea‑level rise with an estimated 15 % higher accuracy than previous global models, providing valuable constraints for climate‑change studies. Regarding reference frames and Earth‑rotation, the Russian network was expanded by more than 150 new GNSS stations, especially in under‑sampled high‑latitude zones, thereby increasing observation density and strengthening ties to the global ITRF. High‑precision Earth Rotation Service measurements achieved daily pole‑position and length‑of‑day determinations at the 0.1 milliarcsecond level, enabling refined analyses of angular momentum exchange between the solid Earth, atmosphere, and oceans. Theoretical contributions include the development of a statistical‑optimization framework that couples nonlinear dynamics with stochastic parameter estimation, allowing the detection of subtle, asymmetric deformations that are missed by linearized approaches. Although the report acknowledges that some research outcomes were omitted for “objective reasons,” it outlines forthcoming publications that will address these gaps. Overall, the document demonstrates that Russian geodesists have leveraged indigenous satellite assets, advanced data‑fusion techniques, and sophisticated modeling to make substantive contributions to the global geodetic community. The anticipated continuation of these efforts over the next decade is expected to further enhance the accuracy of global reference frames, improve our understanding of Earth’s dynamic processes, and provide critical data for climate‑impact assessments.