Bulletin KRASEC. Phys. & Math. Sci, 2015, V. 11, №. 2, pp. 41-50. ISSN 2313-0156

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DOI: 10.18454/2313-0156-2015-11-2-41-50

MATHEMATICAL MODELING

MSC 97A80

REVERSALS IN A GEODYNAMO MODEL DRIVEN BY 6-CELL CONVECTION

G.M. Vodinchar¹², L.K. Feshchenko²

¹Institute of Cosmophysical Research and Radio Wave Propagation, Far-Eastern Branch,
Russian Academy of Sciences, 684034, Kamchatskiy Kray, Paratunka, Mirnaya st., 7, Russia.
²Vitus Bering Kamchatka State University, 683031, Petropavlovsk-Kamchatsky, Pogranichnaya st., 4, Russia.

E-mail: gvodinchar@ikir.ru.

A large-scale geodynamo model based on indirect data of density inhomogeneities in the Earth’s liquid core is described. Convective structure is correlated with a spherical harmonic Y24 , which defines the basic poloidal component of the velocity. The Coriolis drift of this mode determines the toroidal component of the velocity. Thus, a 6-cell convective structure is formed. The model takes into account the inverse effect of the magnetic field on convection.It was ascertained that the model realizes a stable regime of field generation. The convection velocity and the dipole component of the magnetic field are close to the observed ones.

Key words: geodynamo, geomagnetic field reversals, convection.

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For citation: Vodinchar G.M., Feshchenko L.K. Reversals in a geodynamo model driven by 6-cell convection. Bulletin KRASEC. Physical and Mathematical Sciences 2015, vol. 11, issue 2, 41-50. DOI: 10.18454/2313-0156-2015-11-2-41-50.

Original article submitted: 17.11.2015

  
   Vod

  Vodinchar Gleb Mikhailovich – Ph.D. (Phys. Math.), Head of Lab. Modeling of physical processes, Institute of Cosmophysical Researches and Radio Wave Propagation FEB RAS, Associate Professor, Dept. Mathematics & Physics, Vitus Bering Kamchatka State University.

 

 

 

Feshenko   

  Feshenko Lubov Konstantinovna – Ph.D. (Phys. & Math.), Research Scientist of Lab. Modeling of physical processes, Institute of Cosmophysical Researches and Radio Wave Propagation FEB RAS.

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