ITRF2020

ITRF2020 is the new realization of the International Terrestrial Reference System. Following the procedure already used for previous ITRF solutions, the ITRF2020 uses as input data time series of station positions and Earth Orientation Parameters (EOPs) provided by the Technique Centers of the four space geodetic techniques (VLBI, SLR, GNSS and DORIS), as well as local ties at colocation sites. The International Laser Ranging Service (ILRS) official contribution to ITRF2020 is publicly available at the ILRS Data Center at https://doi.org/10.5067/SLR/slr_itrf20200_repro2020_001 and described in https://itrf.ign.fr/docs/solutions/itrf2020/The_ILRS_contribution_to_ITRF2020_description_2022.09.23.pdf. The International DORIS Service (IDS) official contribution to ITRF2020 is publicly available at the IDS Data Centers at https://doi.org/10.24400/312072/i01-2021.001 and described in https://itrf.ign.fr/docs/solutions/itrf2020/IDS-contribution-to-ITRF2020_v1.pdf and Moreaux et al. (2022; https://doi.org/10.1016/j.asr.2022.07.012). The International VLBI Service (IVS) official contribution to ITRF2020 is described in and Hellmers et al. (2022; https://doi.org/10.1007/1345_2022_170). The International GNSS Service (IGS) official contribution to ITRF2020 is described in https://itrf.ign.fr/docs/solutions/itrf2020/IGS-contribution-to-ITRF2020.pdf. Based on completely reprocessed solutions of the four techniques, the ITRF2020 is expected to be an improved solution compared to ITF2014. A number of innovations were introduced in the ITRF2020 processing, including: The time series of the four techniques were stacked all together, adding local ties and equating station velocities and seasonal signals at colocation sites; Annual and semi-annual terms were estimated for stations of the 4 techniques with sufficient time spans; Post-Seismic Deformation (PSD) models for stations subject to major earthquakes were determined by fitting GNSS/IGS data. The PSD models were then applied to the 3 other technique time series at earthquake colocation sites.