Bridging the gap between GRACE and GRACE Follow-On by combining high–low satellite-to-satellite tracking data and satellite laser ranging

authored by
Matthias Weigelt, Adrian Jäggi, Ulrich Meyer, Daniel Arnold, Torsten Mayer-Gürr, Felix Öhlinger, Krzysztof Sośnica, Sahar Ebadi, Steffen Schön, Holger Steffen
Abstract

The satellite missions GRACE and GRACE Follow-On have undoubtedly been the most important sources to observe mass transport on global scales. Within the Combination Service for Time-Variable Gravity Fields (COST-G), gravity field solutions from various processing centers are being combined to improve the signal-to-noise ratio and further increase the spatial resolution. The time series of monthly gravity field solutions suffer from a data gap of about one year between the two missions GRACE and GRACE Follow-On among several smaller data gaps. We present an intermediate technique bridging the gap between the two missions allowing (1) for a continued and uninterrupted time series of mass observations and (2) to compare, cross-validate and link the two time series. We focus on the combination of high-low satellite-to-satellite tracking (HL-SST) of low-Earth orbiting satellites by GPS in combination with satellite laser ranging (SLR), where SLR contributes to the very low degrees and HL-SST is able to provide the higher spatial resolution at an lower overall precision compared to GRACE-like solutions. We present a complete series covering the period from 2003 to 2022 filling the gaps of GRACE and between the missions. The achieved spatial resolution is approximately 700 km at a monthly temporal resolutions throughout the time period of interest. For the purpose of demonstrating possible applications, we estimate the low degree glacial isostatic adjustment signal in Fennoscandia and North America. In both cases, the location, the signal strength and extend of the signal coincide well with GRACE/GRACE-FO solutions achieving 99.5% and 86.5% correlation, respectively.

Organisation(s)
Institute of Geodesy
External Organisation(s)
German Aerospace Center (DLR)
University of Bern
Graz University of Technology
Wrocław University of Environmental and Life Sciences
Lantmäteriet - The Swedish Mapping, Cadastral, and Land Registration Authority
Type
Article
Journal
Journal of geodesy
Volume
98
ISSN
0949-7714
Publication date
13.09.2024
Publication status
Published
Peer reviewed
Yes
ASJC Scopus subject areas
Geophysics, Geochemistry and Petrology, Computers in Earth Sciences
Electronic version(s)
https://doi.org/10.1007/s00190-024-01888-5 (Access: Open)