Atmospheric attraction computation service (Atmacs)

News

2025/02/05: Sign change in NTOL

In order to keep the same sign convention as it is for the atmospheric corrections, the sign of the non-tidal ocean loading (NTOL) corrections was inverted for all time series. Now the convention is the same one as it is for the atmospheric corrections.

2024/04/26: Operational implementation of non-tidal ocean loading effects

Non-tidal ocean loading (NTOL) effects have been implemented in the operational routine of Atmacs. These are based on an ocean simulation of the Max-Planck-Institute Ocean Model (MPIOM) forced by atmospheric data from the Operational ECMWF model. NTOL effects are computed with the SPOTL software in collaboration with GFZ and are available since the epoch 2000-01-01 with a time resolution of 3-hours and for all stations.

2023/07/01: New updates in the atmospheric computation scheme

The routine operation of Atmacs has been resumed. A revision of the loading effects over oceans has been performed allowing to further reduce the variability of gravity residuals recorded with superconducting gravimeters, also improving the compatibility with non-tidal ocean models.
Main improvements:

• The Inverse Barometer assumption is now consistently implemented, considering the compensating Newtonian attraction effect of the oceans to atmospheric pressure changes.
• The ocean mass conservation has been included in the computation of deformation effects.
• A detailed land-sea mask was implemented, also accounting for major lakes.

To ensure the consistency with previous solutions, all updates will be included as an additional column in the station files for the whole period of the ICON-Global model (2015-02-23).

For more details see:
Antokoletz, ED, Wziontek, H, Dobslaw, H, Balidakis, K, Klügel, T, Oreiro, FA, Tocho, CN (2023). Combining atmospheric and non-tidal ocean loading effects to correct high precision gravity time-series, Geophysical Journal International, Volume 236, Issue 1, January 2024, Pages 88-98, https://doi.org/10.1093/gji/ggad371

Previous updates:

• 2023/06/01:
  Due to the change in the amount of layers of the ICON-models, a gap in the time series was existing between 2022/11/23 00:00 and 2022/12/18 00:00. The gap has now been solved.
• 2023/02/15:
  The routine computation of ICON-EU was interrupted. From now on, only atmospheric corrections based on the global solution of ICON-models are provided.
• 2023/01/20:
  Problems with the new datasets have been discovered. Please don't use results from 2022/11/23 and later. They will be recomputed as soon as we have solved the problem.
• 2022/11/23: Changes for ICON-models, extending from 90 to 120 layers for the global model and from 60 to 74 for ICON-EU.