A Heteroclinic Model of Geodynamo Reversals and Excursions

  • I. Melbourne
  • M.R.E. Proctor
  • A.M. Rucklidge
Part of the NATO Science Series book series (NAII, volume 26)


The Earth’s magnetic field is by and large a steady dipole, but its history has been punctuated by intermittent excursions and reversals. This is at least superficially similar to the behaviour of differential equations containing structurally stable heteroclinic cycles. We present a model of the geodynamo that is based on the symmetries of velocity fields in a rotating spherical shell, and that contains such a cycle. Patterns of excursions and reversals that resemble the geomagnetic record can be obtained by introducing small symmetry-breaking terms.


Heteroclinic Cycle Geomagnetic Secular Variation Cumulative Plot Palaeomagnetic Data Kinematic Dynamo 
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Copyright information

© Springer Science+Business Media Dordrecht 2001

Authors and Affiliations

  • I. Melbourne
    • 1
  • M.R.E. Proctor
    • 2
  • A.M. Rucklidge
    • 2
  1. 1.Department of MathematicsUniversity of HoustonHoustonUSA
  2. 2.Department of Applied Mathematics and Theoretical PhysicsUniversity of CambridgeCambridgeEngland

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