– the intergovernmental organization through which Member States act together
     on matters related to measurement science and measurement standards.
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International Association of Geodesy (IAG)

The International Association of Geodesy (IAG) is a scientific organization in the field of geodesy. It promotes scientific cooperation and research in geodesy on a global scale and contributes to it through its various research bodies. It is an active member of the International Union of Geodesy and Geophysics (IUGG) which itself is a member of the International Council for Science (ICSU).

Within the IAG, the Global Geodetic Observing System (GGOS) organization provides a governing structure, working groups, bureaux and coordination entities. Through the IAG Services, GGOS coordinates global infrastructure (geodetic networks, data archives, and processing and analysis centres), and makes available products mainly for scientific users but also, to a limited extent, for society at large. Resources for GGOS are provided by many national agencies, research institutions and individuals on a best-effort basis.

Time scales are a critical need within the IAG community, which relies on the time metrology community and in particular on the BIPM for the provision of the time references. Interaction between time and frequency metrology and the IAG has increased with the perspectives of improving the knowledge of the Earth's gravitational field using very accurate clocks.

Links between the BIPM and the IAG:

  • The Time Department of the BIPM is considered as one of the scientific services of the IAG due the impact of its products on geodetic work.
  • Modeling of the planet Earth as necessary for accurate time metrology is provided by the IAG community, based on the observations coordinated by GGOS.
  • The IUGG participates in the CCTF.
  • The BIPM is a member of the GGOS Steering Committee.
  • Dr Gérard Petit is co-chair of the Commission 1/ Commission 2 Joint Working Group 2.1 on Relativistic Geodesy.

BIPM contact(s):
IAG contact(s):
  • Prof. Hermann Drewes, IAG Secretary General
  • Dr Hansjörg Kutterer, CGOS Chair

Organization: