Liaison : International Association of Geodesy (IAG)


Links between the BIPM and the IAG

  • The International Union of Geodesy and Geophysics (IUGG) participates in the CCTF.
  • Dr Gérard Petit (BIPM Time Department) chairs the IAG Working Group Q. 3: Relativistic geodesy with clocks of the IAG Project - Novel Sensors and Quantum Technology for Geodesy (QuGe).


The IAG 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 IUGG which itself is a member of the International Council for Science (ICSU).

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.



Dr Gérard Petit

Time Department

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