ITRF2020 Station Position Kinematic Model

To adequately describe the shape of the deforming Earth's surface, the ITRF2020 is provided as an augmented reference frame where the temporal station positions are modeled by a piece-wise linear part, and parametric functions describing annual and semi-annual displacements, as well as Post-Seismic Deformation (PSD) for stations subject to major earthquakes. The paper outlines the ITRF2020 analysis strategy and combination model that integrate time series of station positions and Earth Orientation Parameters provided by the IAG technique services of the four space geodetic techniques (DORIS, GNSS, SLR, VLBI). After recalling and discussing the main ITRF2020 features, we deliver some recommendations on how to consistently use the ITRF2020 station position kinematic model that includes the PSD parametric functions, the station seasonal signals expressed in either the Earth Center of Mass (CM) or the Center of Figure (CF) frames, the corresponding geocenter motion, that is the motion of the Center of Mass with respect to the Center of Figure of the solid Earth's surface.