ITRFxxxx Realisations

The International Terrestrial Reference Frame (ITRF) provides a precise, time-dependent set of three-dimensional coordinates and velocities for a global network of geodetic stations, thereby realizing the International Terrestrial Reference System (ITRS). It is derived from the combination of observations from multiple space geodetic techniques — GNSS, VLBI, SLR, and DORIS — which together ensure high accuracy, long-term stability, and global consistency. The ITRF forms the fundamental reference for precise positioning, satellite navigation, Earth observation, and studies of geodynamic processes such as plate tectonics, sea level change, and mass redistribution in the Earth system.

Each realization of the frame, denoted ITRFxxxx, incorporates the most recent observations and improved models available up to the year indicated by “xxxx.” Periodic updates integrate new data, refined geophysical models, and improved analysis strategies, leading to progressively higher accuracy and internal consistency. Major realizations include ITRF2000, ITRF2005, ITRF2008, ITRF2014, and ITRF2020, with earlier versions such as ITRF94, ITRF96, and ITRF97. More recent updates, such as ITRF2020-u2023 and ITRF2020-u2024, provide incremental improvements while maintaining consistency with the ITRF2020 reference. Each new realization delivers a more precise and stable global reference frame, supporting increasingly demanding scientific and practical applications in geodesy and Earth system monitoring.