Time-variable gravity field determination from GRACE Follow-On data usingthe Celestial Mechanics Approach extended by empirical noise modelling

Lasser, Martin; Meyer, Ulrich; Arnold, Daniel; Jäggi, Adrian (18 October 2022). Time-variable gravity field determination from GRACE Follow-On data usingthe Celestial Mechanics Approach extended by empirical noise modelling (Unpublished). In: GRACE Follow-On Science Team Meeting 2022. Potsdam, Germany. 18. Oct. 2022.

[img]
Preview
Text
presentation-gstm2022_Lasser.pdf - Presentation
Available under License BORIS Standard License.

Download (5MB) | Preview

We study gravity field determination from GRACE Follow-On satellite-to-satellite tracking using the inter-satellite K-band link and kinematic positions of the satellites as observations and pseudo- observations respectively. A key component of any model is the accurate specification of its quality. In the case of gravity field modelling from satellite data with the Celestial Mechanics Approach (CMA) a least-squares adjustment is performed to obtain a monthly solution of the Earthâ?Ts gravity field. However, the jointly estimated formal errors usually do not reflect the error level that could be expected but provides much lower error estimates. We present gravity field solutions computed with the CMA and extend it by an empirical modelling of the noise based on the post-fit residuals between the final GRACE Follow-On orbits, that are co-estimated together with the gravity field, and the observations, expressed in position residuals to the kinematic positions and in K-band range-rate residuals. We compare and validate the solutions that use empirical modelling with solutions from the operational GRACE Follow-On processing at AIUB by examining the stochastic behaviour of the respective post-fit residuals, by investigating areas where a low noise is expected and by inspecting the mass trend estimates in certain areas of global interest. Finally, we investigate the influence of the empirically weighted solutions in a combination of monthly gravity fields based on other approaches as it is done by the Combination Service for Time-variable Gravity fields (COST-G) and make use of noise and signal assessment applying the quality control tools routinely used in the frame of COST-G.

Item Type:

Conference or Workshop Item (Speech)

Division/Institute:

08 Faculty of Science > Institute of Astronomy

UniBE Contributor:

Lasser, Martin, Meyer, Ulrich, Arnold, Daniel, Jäggi, Adrian

Subjects:

500 Science > 520 Astronomy

Language:

English

Submitter:

Pierre Fridez

Date Deposited:

28 Mar 2023 15:08

Last Modified:

28 Mar 2023 23:27

Additional Information:

Presentation

BORIS DOI:

10.48350/180753

URI:

https://boris.unibe.ch/id/eprint/180753

Actions (login required)

Edit item Edit item
Provide Feedback