Assessing the stability of AOD1B atmosphere–ocean non-tidal background modelling for climate applications of satellite gravity data: long-term trends and 3-hourly tendencies

authored by
Linus Shihora, Kyriakos Balidakis, Robert Dill, Henryk Dobslaw
Abstract

The GRACE Atmosphere and Ocean Level-1B (AOD1B) product is routinely applied in the processing of satellite gravimetry data to mitigate the impact of temporal aliasing. Spurious trends, low-frequency signals or bias jumps in the background model data can, if unaccounted for, introduce biases into the global gravity solutions which might be interpreted erroneously in subsequent geophysical analyses. Here, we examine the most recent release, RL07, of AOD1B for such artefacts. A focus is placed on the transition from the atmospheric re-analysis ERA5 to operational weather model data, in January 2018, which coincides with the gap between the missions GRACE and GRACE-FO. We find that linear trends computed from 1975 to 2020 are well below 30 Pa a-1 for all components of RL07. The assessment of 3-hourly tendencies gives no indication of bias jumps and shows that the transition in atmospheric data does not have an adverse effect on the consistency of RL07. We conclude with a comparison of the variability of both AOD1B RL06 and RL07 in the context of their application in satellite gravimetry.

External Organisation(s)
Helmholtz Centre Potsdam - German Research Centre for Geosciences
Type
Article
Journal
Geophysical journal international
Volume
234
Pages
1063-1072
No. of pages
10
ISSN
0956-540X
Publication date
08.2023
Publication status
Published
Peer reviewed
Yes
Sustainable Development Goals
SDG 13 - Climate Action
Electronic version(s)
https://doi.org/10.1093/gji/ggad119 (Access: Unknown)