Gravity field models derived from Swarm GPS data

Gravity field models derived from Swarm GPS data

De Teixeira Da Encarnação, J. (TU Delft Astrodynamics & Space Missions)
Arnold, Daniel (University of Bern)
Bezděk, Aleš (Czech Academy of Sciences and Arts)
Dahle, Christoph (University of Bern)
Doornbos, E.N. (TU Delft Astrodynamics & Space Missions)
van den IJssel, J.A.A. (TU Delft Astrodynamics & Space Missions)
Jäggi, Adrian (University of Bern)
Mayer-Gürr, Torsten (Graz University of Technology)
Sebera, Josef (Czech Academy of Sciences and Arts)
Visser, P.N.A.M. (TU Delft Astrodynamics & Space Missions)
Zehentner, Norbert (Graz University of Technology)

2016-12-01

It is of great interest to numerous geophysical studies that the time series of global gravity field models derived from Gravity Recovery and Climate Experiment (GRACE) data remains uninterrupted after the end of this mission. With this in mind, some institutes have been spending efforts to estimate gravity field models from alternative sources of gravimetric data. This study focuses on the gravity field solutions estimated from Swarm global positioning system (GPS) data, produced by the Astronomical Institute of the University of Bern, the Astronomical Institute (ASU, Czech Academy of Sciences) and Institute of Geodesy (IfG, Graz University of Technology). The three sets of solutions are based on different approaches, namely the celestial mechanics approach, the acceleration approach and the short-arc approach, respectively. We derive the maximum spatial resolution of the time-varying gravity signal in the Swarm gravity field models to be degree 12, in comparison with the more accurate models obtained from K-band ranging data of GRACE. We demonstrate that the combination of the GPS-driven models produced with the three different approaches improves the accuracy in all analysed monthly solutions, with respect to any of them. In other words, the combined gravity field model consistently benefits from the individual strengths of each separate solution. The improved accuracy of the combined model is expected to bring benefits to the geophysical studies during the period when no dedicated gravimetric mission is operational.

GRACE
Gravity field
High-low satellite-to-satellite tracking
Swarm

http://resolver.tudelft.nl/uuid:41685693-7431-441e-9ad5-368b132c308b

https://doi.org/10.1186/s40623-016-0499-9

1343-8832

Earth, Planets and Space, 68 (1)

Institutional Repository

journal article

© 2016 J. De Teixeira Da Encarnação, Daniel Arnold, Aleš Bezděk, Christoph Dahle, E.N. Doornbos, J.A.A. van den IJssel, Adrian Jäggi, Torsten Mayer-Gürr, Josef Sebera, P.N.A.M. Visser, Norbert Zehentner