A Non-tidal Atmospheric Loading Model: On Its Quality and Impacts on Orbit Determination and C20 from SLR

Based on European Centre for Medium-Range Weather Forecasts (ECMWF) ERA-Interim data we model displacements of global station coordinates due to non-tidal atmospheric loading based on Farrel’s theory. We compare these displacements to publicly available external displacements. We apply our displacements to Satellite Laser Ranging (SLR) data processing over a recent 6 years period of the LAGEOS, LARES, AJISAI, STARLETTE and STELLA geodetic satellites. We assess the impact of the loading model on the orbital fits of these missions. Indeed a tiny improvement shows up. We also quantify the impact of the non-tidal loading model on the large scale figure of the Earth expressed in terms of weekly C(2,0) harmonics. It turns out that here no effect is visible.