Skip to main contentSkip to search
Episciences
Open Access Journals
Sign in(new window)
Journal of Studies of Earth’s Deep Interior logo
Journal of Studies of Earth’s Deep Interior
Journal of Studies of Earth’s Deep Interior logo
Journal of Studies of Earth’s Deep Interior
Sign in(new window)
Articles & Issues
All articlesAll accepted articlesAll volumesLast volumeAuthors
About
The journalNews
Boards
Publish
For authorsEthical charter
Submit
Journal of Studies of Earth’s Deep Interior logo
Journal's leaflet
|
Contact
|
Credits
eISSN 3099-2877
|
RSS
|
Atom
Episciences
Documentation
|
Acknowledgements
|
Publishing policy
Accessibility: non-compliant
|
Legal mentions
|
Privacy statement
|
Terms of use
  1. Home > Articles & Issues >
  2. Articles >
  3. Principal component ...
Article

Principal component analysis of the 2010 reversal of core-surface flow beneath the Pacific Ocean

Frederik Dahl Madsen ORCID (1), Isobel Howard ORCID (1), William Brown ORCID (2), Kathryn Whaler ORCID (3)
(1) University of Edinburgh, School of GeoSciences
(2) British Geological Survey - Edinburgh Office
(3) University of Edinburgh
Download article
Open on Zenodo
Submitted on
January 9, 2026
Accepted on
April 20, 2026
Published on
May 6, 2026
Last modified on
June 9, 2026
Volume 2
Volume 2
DOI
10.46298/jsedi.17268
Indicators
20489
Views
8750
Downloads

Principal component analysis of the 2010 reversal of core-surface flow beneath the Pacific Ocean

Frederik Dahl Madsen ORCID (1), Isobel Howard ORCID (1), William Brown ORCID (2), Kathryn Whaler ORCID (3)
(1) University of Edinburgh, School of GeoSciences
(2) British Geological Survey - Edinburgh Office
(3) University of Edinburgh
Abstract
This paper is published after peer review in the Journal of Studies of Earth's Deep Interior (jSEDI).In this paper, we investigate the behaviour of the fluid flow in the Earth's outre core throughout the 21st century. The flow of the liquid iron cocktail in the Earth's outer core generates the geomagnetic field and its rate of change, the secular variation. Assuming that magnetic diffusion is negligible on timescales shorter than 100 years, we can invert SV observations from ground observatories and geomagnetic satellites for models of the fluid flow at the top of the core. We investigate core-surface flow, modelled from observations of SV from 1997 to 2025. Historically, the core-surface flow has been predominantly westward, as required to maintain a westward-drifting magnetic field, which is associated with a planetary gyre of westward flow, offset from the Earth’s rotation axis. This gyre does not affect the flow in the equatorial Pacific, and we find that the flow here changes in 2010 from weakly westward to strongly eastward. Our model suggest that the Pacific eastwards flow has been weakening since 2020. The rise of the strong eastward flow in the Pacific is contemporary with a change in behaviour in the inner core, as observed from geodesy and seismology, and we hypothesise that these changes in the deep interior triggered the inferred changes in flow beneath the Pacific. 
Keywords
  • Geomagnetism
  • Core dynamics
Linked publications - datasets - software
  • Is supplemented by
    https://zenodo.org/records/20268724
Preview
Loading PDF preview...
References

  1. Amit, H. and P. Olson (2004). Helical core flow from geomagnetic secular variation. Phys. Earth Planet. Inter. 147.1, 1–25. doi: 10.1016/J.PEPI.2004.02.006.

    DOI : 10.1016/J.PEPI.2004.02.006

  2. Amit, H. and M. A. Pais (2013). Differences between tangential geostrophy and columnar flow. Geophys. J. Int. 194.1, 145–157. doi: 10.1093/gji/ggt077.

    DOI : 10.1093/gji/ggt077

  3. Aubert, J. (2023). State and evolution of the geodynamo from numerical models reaching the physical conditions of Earth’s core. Geophys. J. Int. 235.1, 468–487. doi: 10.1093/gji/ggad229.

    DOI : 10.1093/gji/ggad229

  4. Beggan, C. and K. Whaler (2008). Core flow modelling assumptions. Phys. Earth Planet. Inter. 167.3-4, 217–222. doi: 10.1016/J.PEPI.2008.04.011.

    DOI : 10.1016/J.PEPI.2008.04.011

  5. Bloxham, J. (1988). The determination of fluid flow at the core surface from geomagnetic observations. Mathematical Geophysics: A Survey of Recent Developments in Seismology and Geodynamics. Ed. by N. J. Vlaar, G. Nolet, M. J. R. Wortel, and S. A. P. L. Cloetingh. Dordrecht: Springer Netherlands, pp. 189–208. doi: 10.1007/978-94-009-2857- 2_9.

  6. Brown, W. J., J. E. Mound, and P. W. Livermore (2013). Jerks abound: An analysis of geomagnetic observatory data from 1957 to 2008. Phys. Earth Planet. Inter. 223, 62–76. doi: 10.1016/J.PEPI.2013.06.001.

    DOI : 10.1016/J.PEPI.2013.06.001

  7. Cain, J. C., Z. Wang, D. R. Schmitz, and J. Meyer (1989). The geomagnetic spectrum for 1980 and core-crustal separation. Geophys. J. Int. 97.3, 443–447. doi: 10.1111/j.1365-246X.1989.tb00514.x.

    DOI : 10.1111/j.1365-246X.1989.tb00514.x

  8. Chulliat, A. and S. Maus (2014). Geomagnetic secular acceleration, jerks, and a localized standing wave at the core surface from 2000 to 2010. J. Geophys. Res.: Solid Earth 119.3, 1531–1543. doi: 10.1002/2013JB010604.

    DOI : 10.1002/2013JB010604

  9. Chulliat, A., E. Thébault, and G. Hulot (2010). Core field acceleration pulse as a common cause of the 2003 and 2007 geomagnetic jerks. Geophys. Res. Lett. 37.7. doi: 10.1029/2009GL042019.

    DOI : 10.1029/2009GL042019

  10. Claveau, R., N. Gillet, P.-O. Amblard, and C. C. Finlay (2025). Broadband a priori temporal cross-covariances for the geomagnetic inverse problem: application to the satellite era. Earth, Planets and Space 77.1, 126. doi: 10.1186/s40623-025-02248-z.

    DOI : 10.1186/s40623-025-02248-z

  11. Courtillot, V., J. Ducruix, and J. L. Le Mouël (1978). Sur une accélération récente de la variation séculaire du champ magnétique terrestre. C. R. Acad. Sci. D 287.12, 1095–1098.

  12. Domingos, J., M. A. Pais, D. Jault, and M. Mandea (2019). Temporal resolution of internal magnetic field modes from satellite data. Earth, Planets and Space 71.1, 2. doi: 10.1186/s40623-018-0983-5.

    DOI : 10.1186/s40623-018-0983-5

  13. Finlay, C. C., N. Gillet, J. Aubert, P. W. Livermore, and D. Jault (2023). Gyres, jets and waves in the Earth’s core. Nature Reviews Earth & Environment. doi: 10.1038/s43017-023-00425-w.

    DOI : 10.1038/s43017-023-00425-w

  14. Friis-Christensen, E., H. Lühr, and G. Hulot (2006). Swarm: A constellation to study the Earth’s magnetic field. Earth, Planets and Space 58.4, 351–358. doi: 10.1186/BF03351933.

    DOI : 10.1186/BF03351933

  15. Gibson, J. F., J. Doyne Farmer, M. Casdagli, and S. Eubank (1992). An analytic approach to practical state space reconstruction. Physica D: Nonlinear Phenomena 57.1-2, 1–30. doi: 10.1016/0167-2789(92)90085-2.

    DOI : 10.1016/0167-2789(92)90085-2

  16. Gillet, N., F. Dall’Asta, P.-O. Amblard, R. Claveau, and J. Aubert (2024). Waves in Earth’s core and geomagnetic field forecast. Phys. Earth Planet. Inter. 357, 107284. doi: 10.1016/j.pepi.2024.107284.

    DOI : 10.1016/j.pepi.2024.107284

  17. Gillet, N., L. Huder, and J. Aubert (2019). A reduced stochastic model of core surface dynamics based on geodynamo simulations. Geophys. J. Int. 219.1, 522–539. doi: 10.1093/gji/ggz313.

    DOI : 10.1093/gji/ggz313