A Review of Space Geodetic Technique Seasonal Displacements Based on ITRF2020 Results

Abstract

AbstractThe new release of the International Terrestrial Reference Frame, ITRF2020, differs from ITRF2014 by the addition of parametric functions describing annual and semi-annual displacements for every station. ITRF2020 coordinates are now described with piece-wise linear functions, occasional exponential and logarithmic functions modelling post-seismic displacements and the newly provided seasonal parameters. The paper first shortly presents the ITRF2020 seasonal parameters provided both in the Center of Mass (CM) and in the Center of Fig. (CF) frames. The station-specific seasonal displacements determined by the four space geodetic techniques (DORIS, GNSS, SLR, VLBI) are then reconstructed from the ITRF2020 results in the CF frame. The estimated seasonal signals are shown to agree generally within their uncertainties at co-location sites if a realistic noise model is considered.