Skip to main content
  • Letter
  • Published:

Asymmetric behavior of magnetic dip poles


The north magnetic dip pole velocity has more than doubled in the last 30 years. This observation, together with the decrease in the Earth’s magnetic dipole intensity over the last century has raised the concern of a possible approaching polarity reversal. We show that this rapid variation is in fact to be expected, and will not affect the dipolar field as a whole, but only the north magnetic pole. We demonstrate how this rapid displacement of the north magnetic pole is made possible by the horizontal field morphology. This rapid variation of north magnetic pole position does not imply any important modification of the core processes associated with field generation. The north magnetic pole position being very sensitive to small as well as rapid variations of the field, we show that it can very effectively be used as a passive tracer (or indicator) of field variations. Indeed, its velocity over the last century very accurately indicates the geomagnetic impulses (or jerks) that were so far observed only in observatory data.


  • Alexandrescu, M., D. Gibert, G. Hulot, J.-L. Le Mouël, and G. Saracco, Worldwide analysis of geomagnetic jerks, J. Geophys. Res., 101, 21975–21994, 1996.

    Article  Google Scholar 

  • Barton, C., Survey Tracks Current Position of South Magnetic pole, EOS, 83(27), 291, 2002.

    Article  Google Scholar 

  • Carlut, J., V. Courtillot, and G. Hulot, Over how much time should the geomagnetic field be averaged to obtain the mean paleomagnetic field? Terra Nova, 11(5), 239–243, 2000.

    Article  Google Scholar 

  • Courtillot, V., J. Ducruix, and J.-L. Le Mouël, Sur une accélération récente de la variation séculaire du champ magnétique terrestre, C. R. Acad. Sci. D, 287, 1095–1098, 1978.

    Google Scholar 

  • Fraser-Smith, A. C., Centered and eccentric geomagnetic dipoles and their poles, 1600–1985, Rev. Geophys., 25, 1–16, 1987.

    Article  Google Scholar 

  • Hope, E. R., Linear secular oscillation of the northern magnetic pole, J. Geophys. Res., 62-1, 19–27, 1957.

    Article  Google Scholar 

  • Hulot, G., C. Eymin, B. Langlais, M. Mandea, and N. Olsen, Small-scale structure of the geodynamo inferred from Oersted and Magsat satellite data, Nature, 416, 620–623, 2002.

    Article  Google Scholar 

  • Jackson, A., A. Jonkers, and M. Walker, Four centuries of geomagnetic secular variation from historical records, Phil. Trans. R. Soc. Lond., 358, 957–990, 2000.

    Article  Google Scholar 

  • Langlais, B., M. Mandea, and P. Ultré-Guérard, High-resolution magnetic field modeling: application to MAGSAT and Ørsted data, Phys. Earth Planet. Int., 2003 (in press).

  • Le Huy, M., M. Alexandrescu, G. Hulot, and J.-L. Le Mouël, On the characteristics of successive geomagnetic jerks, Earth Planets Space, 50, 723–732, 1998.

    Article  Google Scholar 

  • Malin, S. R. C., B. H. Hodder, and D. R. Barraclough, Geomagnetic secular variation: A jerk in 1970, in 75th Anniversary Volume of Ebro Observatory, edited by J. O. Cardus, pp. 239–256, Roquetes, Tarragona, Spain, 1983.

    Google Scholar 

  • Mandea, M. and S. Macmillan, International Geomagnetic Reference Field—The Eighth Generation, Earth Planets Space, 52, 1119–1124, 2000.

    Article  Google Scholar 

  • Nagao, H., T. Iyemori, T. Higuchi, S. Nakano, and T. Araki, Local time features of geomagnetic jerks, Earth Planets Space, 54, 119–131, 2002.

    Article  Google Scholar 

  • Newitt, L. R., M. Mandea, L. A. McKee, and J.-J. Orgeval, Recent acceleration of the North Magnetic Pole linked to magnetic jerks, EOS, 83, 381–388, 2002.

    Article  Google Scholar 

  • Olsen, N., R. Holme, G. Hulot, T. Sabaka, T. Neubert, L. Toeffner-Clausen, F. Primdahl, J. Joergensen, J.-M. Leger, D. Barraclough, J. Bloxham, J. Cain, C. Constable, V. Golovkov, A. Jackson, P. Kotze, B. Langlais, S. Macmillan, M. Mandea, J. Merayo, L. Newitt, M. Purucker, T. Risbo, M. Stampe, A. Thomson, and C. Voorhies, Oersted Initial Field Model (OIFM), Geophys. Res. Lett., 27(22), 3607–3610, 2000.

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations


Corresponding author

Correspondence to M. Mandea.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Mandea, M., Dormy, E. Asymmetric behavior of magnetic dip poles. Earth Planet Sp 55, 153–157 (2003).

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: