Using GRACE to Explain Variations in the Earth's Oblateness

Sun, Y.; Riva, R.E.M.; Ditmar, P.G.; Rietbroek, Roelof

doi:10.1029/2018GL080607

Using GRACE to Explain Variations in the Earth's Oblateness

Title

Using GRACE to Explain Variations in the Earth's Oblateness

Author

Sun, Y. (TU Delft Physical and Space Geodesy; Fuzhou University)
Riva, R.E.M. (TU Delft Physical and Space Geodesy)
Ditmar, P.G. (TU Delft Physical and Space Geodesy)
Rietbroek, Roelof (Universität Bonn)

Date

2019

Abstract

We present a new approach to estimate time variations in J2. Those variations are represented as the sum of contributions from individual sources. This approach uses solely Gravity Recovery And Climate Experiment (GRACE) data and the geoid fingerprints of mass redistributions that take place both at the surface and in the interior of the solid Earth. The results agree remarkably well with those based on satellite laser ranging, while estimates of the sources explain the observed variations in J2. Seasonal variations are dominated by terrestrial water storage and by mass redistribution in the atmosphere and ocean. Trends, however, are primarily controlled by the Greenland and Antarctic ice sheets and by glacial isostatic adjustment. The positive trend from surface mass variations is larger than the negative trend due to glacial isostatic adjustment and leads to an overall rising trend during the GRACE period (2002–2017).

Subject

C
Earth's dynamic oblateness
geoid fingerprints
GRACE
J
mass redistribution
J(2)
C-20

To reference this document use:

http://resolver.tudelft.nl/uuid:303371c0-6e5d-460b-8ead-4a4b37b88d80

DOI

https://doi.org/10.1029/2018GL080607

ISSN

0094-8276

Source

Geophysical Research Letters, 46 (1), 158-168

Part of collection

Institutional Repository