Assessment of the International Terrestrial Reference System 2014 realizations by Precise Orbit Determination of SLR Satellites
Event: 2017 Ocean Surface Topography Science Team Meeting
Session: Precision Orbit Determination
Presentation type: Type Oral
A high accuracy, consistent and long-term stable realization of the International Terrestrial Reference System (ITRS) is a basis for the investigations of the global and regional mean sea level changes, dynamics of the points on the Earth's surface, solid Earth deformations, tectonic motion, Earth's rotation, post-glacial rebound, precise orbit determination of the Earth's artificial satellites, precise positioning and navigation on and near the Earth's surface. Three new ITRS realizations were published in 2016. They are DTRF2014 developed at DGFI-TUM (Germany), ITRF2014 developed at IGN LAREG (France) and JTRF2014 developed at JPL (USA). In this presentation, we provide a short description of these new realizations and present the results of the assessment of these realizations by precise orbit determination of ten high and low Earth orbiting geodetic satellites equipped with satellite laser ranging (SLR) retro-reflectors using SLR observations over, in total, a 24-year time interval from 1993.0 to 2017.0. We perform this analysis for LAGEOS-1/2, Etalon-1/2 used for the terrestrial reference frame (TRF) and Earth orientation parameters (EOP) determination for the International Laser Ranging Service (ILRS) contribution to the ITRS 2014 realizations, for altimetry satellite Jason-2, as well as for canon-ball geodetic satellites LARES, Larets, Ajisai, Starlette, Stella used for the improvement of thermosphere models and, together with LAGEOS and Etalon satellites, for the improvement of the low degree Stokes terms of the Earth's gravity field expansion. We show the impact of the ITRS 2014 realizations, as compared to the previous ITRS realization for SLR stations - SLRF2008, on the root-mean-square and mean fits of SLR observations, satellite orbits, weekly estimated mean station-specific range biases, 10-day single satellite sea surface height (SSH) crossover differences and geographically correlated mean SSH errors for Jason-2. We illustrate the importance of modelling non-linear station motions and non-tidal loading corrections to station positions.