Geodetic infrastructure is the starting point of the geodetic value chain. It comprises the observing, data, analysis, and research capabilities required to transform observations into reliable information on the Earth’s shape, gravity field, and orientation. It integrates space-, air-, sea-, and ground-based observations, with terrestrial techniques complementing the global and regional coverage of space-based systems by providing higher spatial and temporal resolution, calibration and validation, and information on local features. Data infrastructure supports the quality-controlled transfer, management, archiving, and dissemination of observations and products in accordance with international standards. Analysis infrastructure enables the consistent processing and integration of observations, while research infrastructure drives technological innovation, scientific advancement, and the integration of geodetic observations into advanced Earth system models.
The following geodetic products are key to realising, monitoring and applying this Essential Geodetic Variable:
Geodetic Space Infrastructure (GSI): comprises the space segment of space geodetic techniques such as quasars for VLBI and satellites for SLR, DORIS, GNSS, gravity field missions, radar and optical satellite altimetry, radar interferometry, radio occultation, etc.
Geodetic Terrestrial Infrastructure (GTI): comprises the ground segments of space geodetic infrastructure (such as station networks and operational centres for data collection, analysis and distribution) as well as the sensors/instruments of terrestrial techniques such as tide gauges, absolute and relative gravity meters (including superconducting and quantum gravity meters), GNSS reflectometry, optical atomic clocks, and geometric angle, distance and levelling methods.
IAG as part of the IUGG
IAG Related Organisations
IAG collaborates closely with numerous organizations within geodesy and beyond. See the list for details.
This website is provided by the IAG Secretariat and the GGOS Coordinating Office, which are hosted by the BEV – Federal Office of Metrology and Surveying (Bundesamt für Eich- und Vermessungswesen) in Vienna, Austria.