Loading [MathJax]/jax/output/HTML-CSS/fonts/TeX/fontdata.js
Preprints
https://doi.org/10.5194/egusphere-2023-856
https://doi.org/10.5194/egusphere-2023-856
06 Jun 2023
 | 06 Jun 2023

Earth's core variability from the magnetic and gravity field observations

Anita Thea Saraswati, Olivier de Viron, and Mioara Mandea

Abstract. The motions of the liquid within the Earth's outer core lead to magnetic field variations together with mass distribution changes. As the core is not accessible to direct observation, our knowledge of the Earth’s liquid core dynamics only relies on indirect information sources. Mainly generated by the core dynamics, the surface geomagnetic field provides information about the variations of the fluid motion at the top of the core. The dynamic of the fluid core is also associated with mass distribution changes inside the core, and produces gravitational field time fluctuations. By applying several statistical Blind Source Separation methods to both the gravity and magnetic field time series, we investigate the common space-time variabilities. We report several robust interannual oscillations shared by the two observation sets. Among those, a common mode of around 7 years looks very significant. Whereas the nature of the driving mechanism of the coupled variability remains unclear, the spatial and temporal properties of the common signal are compatible with a core origin.

Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims made in the text, published maps, institutional affiliations, or any other geographical representation in this preprint. The responsibility to include appropriate place names lies with the authors.
Share

Journal article(s) based on this preprint

20 Dec 2023
Earth's core variability from magnetic and gravity field observations
Anita Thea Saraswati, Olivier de Viron, and Mioara Mandea
Solid Earth, 14, 1267–1287, https://doi.org/10.5194/se-14-1267-2023,https://doi.org/10.5194/se-14-1267-2023, 2023
Short summary
Download

The requested preprint has a corresponding peer-reviewed final revised paper. You are encouraged to refer to the final revised version.

Short summary
To understand core dynamics, insight from several possible observables is needed. By applying...
Share