Abstract—Perhaps for the first time, we obtained the distributed volume electric currents determined by the observed geomagnetic dipole. To do that, using the Maxwell’s equations and well-established geodynamo estimates, we have shown that the mean current density in the Earth’s liquid core is several orders of magnitude higher than in the solid core. Correspondingly, current density in our model vanishes in the solid core whereas in the liquid core, from maximally realistic simplifications, it is proportional to the distance to the dipole axis and directed around this axis. Using standard expansions, integrations, and the generally accepted IGRF model, we obtained total currents, the associated power of ohmic dissipation, volume current densities, and the directions of the current axis oriented as a dipole pole from 1900 to 2020.
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ACKNOWLEDGMENTS
We are deeply grateful to the anonymous reviewer for valuable constructive comments that were used to prepare the Discussion section and present the novelty of our results.
Funding
This work was mainly carried out under the projects covered by the state contract of Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation.
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Translated by M. Nazarenko
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Starchenko, S.V., Smirnov, A.Y. Volume Currents of Present-Day Magnetic Dipole in the Earth’s Core. Izv., Phys. Solid Earth 57, 474–478 (2021). https://doi.org/10.1134/S106935132104008X
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DOI: https://doi.org/10.1134/S106935132104008X