About

The ULR5 GPS solution is the result of a reanalysis of 16 years of GPS data from 1995 to 2010. Its vertical velocity field is published in Global and Planetary Change. It is expressed in ITRF2008.

Double-differenced ionosphere-free GPS carrier phase observations from a global network of 420 stations were reanalyzed using GAMIT/GLOBK software version 10.4. The data set covered the period January 1995 to December 2010 and 282 stations out of 420 were co-located with a tide gauge. Station coordinates, satellite orbits, Earth orientation parameters (EOPs), and zenith tropospheric delay parameters every hour, were estimated. Details on the GPS data processing strategy (models, corrections,...) can be found in the IGS-like ULR analysis centre form associated with this solution.

The GPS velocities were obtained in the final step of the analysis which combined the weekly GAMIT/GLOBK global network solutions (station coordinates with full co-variances) from the entire data time span into a long-term solution using CATREF software. This long-term solution (ULR5) was aligned to ITRF2008 using minimal constraints over a selected set of IGS Reference Frame stations. A detailed description can be found in the reference below.