Dynamo Models of the Solar Cycle

  • Paul Charbonneau
Part of the Saas-Fee Advanced Courses book series (SAASFEE, volume 39)


This chapter details a series of dynamo models applicable to the sun and solar-type stars. After introducing the theoretical framework known as mean-field electrodynamics, a series of increasingly complex dynamo models are constructed, with the primary aim of reproducing the various basic observed characteristics of the solar magnetic activity cycle. Global and local magnetohydrodynamcial simulations of solar convection, and dynamo action therein, are also considered, and the resulting magnetic cycles compared and contrasted to those obtained in the simpler dynamo models. The focus throughout the chapter is on the sun, simply because the amount of available observational material on the solar magnetic field and its cycle dwarfs anything else in the astrophysical realm, in terms of spatial and temporal resolution, sensitivity, and time span.


Flux Rope Meridional Flow Dynamo Model Toroidal Field Poloidal Field 
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  79. The production of solar-like magnetic cycles in such simulations is a recent breakthrough. The simulation results presented in Sect. 3.5 are taken from Ghizaru, M., Charbonneau, P., & Smolarkiewicz, P. K.: 2010, Magnetic cycles in global large-eddy simulations of solar convection, Astrophys. J. Lett., 715, L133–L137Google Scholar
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  81. These simulations were computed with the MHD version, developed at the Université de Montréal, of the general purpose hydrodynamical simulation code EULAG; on the latter, Prusa, J. M., Smolarkiewicz, P. K., & Wyszogorodzki, A. A.: 2008, EULAG, a computational model for multi-scale flows, Comp. Fluids, 37, 1193–1207Google Scholar
  82. as well as the EULAG web-page:
  83. The numerical simulation results displayed on Fig. 3.25 is publicly available at:
  84. Explanatory notes describing the simulation framework are also provided there, and discussed in greated detail in Stein, R. F., Lagerfjärd, A., Nordlund, Å., & Georgobiani, D.: 2011, Solar flux emergence simulations, Solar Phys., 268, 271–282Google Scholar
  85. In a similar vein, do not miss: Cheung, M. C. M., Rempel, M., Title, A. M., & Schüssler, M.: 2010, Simulation of the formation of a solar active region, Astrophys. J. 720, 233–244Google Scholar
  86. On the observational measurements and characterization of small-scale solar surface magnetic structures, and the potential implications for dynamo processes, see Parnell, C. E., DeForest, C. E., Hagenaar, H. J., Johnston, B. A., Lamb, D. A., & Welsch, B. T.: 2009, A power-law distribution of solar magnetic fields over more than five decades in flux, Astrophys. J. 698, 75–82Google Scholar
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© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  1. 1.Département de physiqueUniversité de MontréalMontrealCanada

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