EGU2020-11837, updated on 12 Jun 2020
EGU General Assembly 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

The correction for polar motion in gravimetry and in 3-D positioning

Jaakko Mäkinen
Jaakko Mäkinen
  • Finnish Geospatial Research Institute FGI, Department of Geodesy and Geodynamics, Masala, Finland (

In the correction for polar motion, terrestrial gravimetry and 3-D positioning follow different conventions. The 3-D positions are corrected to refer to the "mean pole" (IERS Conventions 2010) or to the "secular pole" (IERS update working version since 2018). In any case, the pole reference evolves in time and describes the track of secular or low-frequency polar wander. However, in terrestrial gravimetry the gravity values are corrected to refer to the IERS Reference Pole, a fixed quantity. This may lead to discrepancies when for instance gravity change rates from absolute gravity measurements are compared with vertical velocities from GNSS. I discuss the size and geographical distribution of the possible discrepancies.

How to cite: Mäkinen, J.: The correction for polar motion in gravimetry and in 3-D positioning, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11837,, 2020