An earth-like numerical dynamo model

ABSTRACT The mechanism by which the Earth and other planets maintain their magnetic fields against ohmic decay is among the longest standing problems in planetary science. Although it is

widely acknowledged that these fields are maintained by dynamo action, the mechanism by which the dynamo operates is in large part not understood. Numerical simulations of the dynamo process

in the Earth's core1,2,3,4 have produced magnetic fields that resemble the Earth's field, but it is unclear whether these models accurately represent the extremely low values of

viscosity believed to be appropriate to the core. Here we describe the results of a numerical investigation of the dynamo process that adopts an alternative approach5 to this problem in

which, through the judicious choice of boundary conditions, the effects of viscosity are rendered unimportant. We thereby obtain a solution that at leading order operates in an Earth-like

dynamical regime. The morphology and evolution of the magnetic field and the fluid flow at the core–mantle boundary are similar to those of the Earth, and the field within the core is

qualitatively similar to that proposed on theoretical grounds6. Access through your institution Buy or subscribe This is a preview of subscription content, access via your institution ACCESS

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institutional subscriptions * Read our FAQs * Contact customer support SIMILAR CONTENT BEING VIEWED BY OTHERS LONGITUDINAL STRUCTURE OF EARTH’S MAGNETIC FIELD CONTROLLED BY LOWER MANTLE HEAT

FLOW Article 16 March 2023 SUSTAINING EARTH’S MAGNETIC DYNAMO Article 10 March 2022 WEAK MAGNETIC FIELD CHANGES OVER THE PACIFIC DUE TO HIGH CONDUCTANCE IN LOWERMOST MANTLE Article 29 June

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thank G. Glatzmaier and P. Roberts for many helpful discussions regarding their work and for providing the data sets that were used to prepare Figs 2 and 3 , and P. Olson for critically

reviewing the manuscript. This work was supported by the David and Lucile Packard Foundation and by the NSF. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Department of Earth and Planetary

Sciences, Harvard University, 20 Oxford Street, Cambridge, 02138, Massachusetts, USA Weijia Kuang & Jeremy Bloxham Authors * Weijia Kuang View author publications You can also search for

this author inPubMed Google Scholar * Jeremy Bloxham View author publications You can also search for this author inPubMed Google Scholar RIGHTS AND PERMISSIONS Reprints and permissions

ABOUT THIS ARTICLE CITE THIS ARTICLE Kuang, W., Bloxham, J. An Earth-like numerical dynamo model. _Nature_ 389, 371–374 (1997). https://doi.org/10.1038/38712 Download citation * Received: 12

March 1997 * Accepted: 15 July 1997 * Issue Date: 25 September 1997 * DOI: https://doi.org/10.1038/38712 SHARE THIS ARTICLE Anyone you share the following link with will be able to read

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