Terms of Reference

Reference systems and frames are of primary importance as metrological basis for Earth science based research and applications, satellite navigation and orbit determination as well as for practical applications in positioning, mapping and geo-information related fields. A precisely defined and realized reference frame is needed for an improved understanding of the Earth system, including its rotation and gravity field, sea level change with time, tectonic plate motion and deformation, glacial isostatic adjustment, geocenter motion, deformation due to earthquakes, local subsidence, and other crustal displacements. Commission 1 objectives and related activities deal with the theoretical and operational aspects of how best to define and realize reference systems and how those can be used for practical and scientific applications at different spatio-temporal scales on the deformable Earth. Commission 1 will closely interact with the other IAG Commissions and Services, the ICCT, the ICCC, and the GGOS components where reference system aspects are of concern, to address related problems for the realization of celestial and terrestrial reference systems in conformity with present and future accuracy needs. Commission 1 is also linked with the IUGG/COSPAR joint Sub-Commission B2 (International Coordination of Space Techniques for Geodesy) with the aim to develop links and coordinate the work between various groups engaged in the field of space geodesy and geodynamics.