Comparison between GIPSY OASIS 6.0 and BERNESE 5.0 time series for long term GPS stations in Denmark

We study influence of software on determination of secular uplift rates. For this purpose we process GPS data for three long term permanent GPS stations, SMID, SULD, and BUDP, all located in Denmark (fig 1). To process the GPS data, we use the GIPSY OASIS 6.0 software and the Bernese 5.0 software. For both software, we use the Precise Point Positioning (PPP) strategy and all parameters, including the data time span, are held constant. To make the solutions comparable, we use the same orbit products, oceans load model, antenna phase center offsets model. Our results suggest small difference in uplift rates at SMID and SULD between the GIPSY and the Bernese solutions, however, the differences of ~0.10 mm/yr are within the estimated uncertainty of ~0.17 mm/yr. At BUDP we obtain a slightly larger difference (0.19 mm/yr) between the GIPSY and the Bernese solutions, however, the difference is almost within the estimated uncertainty of 0.18 mm/yr.