A three-dimensional self-consistent computer simulation of a geomagnetic field reversal

@article{Glatzmaiers1995ATS,
  title={A three-dimensional self-consistent computer simulation of a geomagnetic field reversal},
  author={Gary A. Glatzmaiers and P. Roberts},
  journal={Nature},
  year={1995},
  volume={377},
  pages={203-209}
}
A three-dimensional, self-consistent numerical model of the geodynamo is described, that maintains a magnetic field for over 40,000 years. The model, which incorporates a finitely conducting inner core, undergoes several polarity excursions and then, near the end of the simulation, a successful reversal of the dipole moment. This simulated magnetic field reversal shares some features with real reversals of the geomagnetic field, and may provide insight into the geomagnetic reversal mechanism. 
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References

SHOWING 1-10 OF 44 REFERENCES
A three-dimensional convective dynamo solution with rotating and finitely conducting inner core and mantle
We present the first three-dimensional (3D), time-dependent, self-consistent numerical solution of the magneto- hydrodynamic (MHD) equations that describe thermal convection and magnetic fieldExpand
Geomagnetic field morphologies from a kinematic dynamo model
THE Earth's magnetic field is generated by flow of liquid iron in the outer core, acting as a dynamo. In the simple kinematic theory a fluid flow is prescribed and tested for its ability to generateExpand
A model-Z geodynamo
Abstract This paper describes a re-investigation of the geomagnetic dynamo model proposed by Braginsky (1978). This axisymmetric nonlinear model was dominated by Lorentz and Coriolis forces, and wasExpand
Magnetic-flux transport by a convecting layer including dynamical effects
Abstract The work of Drobyshevski and Yuferev (1974) and Arter (1983b) is continued and extended. Magnetic flux distributions are calculated for Rayleigh-Bknard convection with square planform. TheExpand
Intermediate Dynamo Models
We describe a nonlinear, axisymmetric, spherical-shell model of a planetary dynamo. This intermediate-type dynamo model requires a prescribed helicity field (the alpha effect) and a prescribedExpand
Influence of the Earth's inner core on geomagnetic fluctuations and reversals
IN view of its relatively small size (one-third the radius of the outer core), many geodynamo models neglect the inner core entirely1, or otherwise treat it as a non-conducting insulator2,3. In aExpand
Turbulent dynamos driven by convection
The generation of magnetic fields by the turbulent motions of a conducting fluid driven by thermal convection in the incompressible case is studied by direct numerical simulations at Rayleigh numbersExpand
Computer simulation of a magnetohydrodynamic dynamo. II
A computer simulation of a magnetohydrodynamic dynamo in a rapidly rotating spherical shell is performed. Extensive parameter runs are carried out changing electrical resistivity. When resistivity isExpand
Geomagnetic field intensity and reversals during the past four million years
A long and continuous record of the geomagnetic field intensity shows that intensity variations are dominated by two modes. Major episodes of field regeneration prevail on timescales of a fewExpand
Dipolar reversal states of the geomagnetic field and core–mantle dynamics
Palaeomagnetic records from lavas suggest that at least two specific inclined dipolar field configurations have dominated the reversal process for the past ten million years. These long-lived statesExpand
...
1
2
3
4
5
...