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arXiv · 2301.05452

A synchronized two-dimensional $\alpha-\Omega$ model of the solar dynamo

M. Klevs·F. Stefani·L. Jouve
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Abstract

We consider a conventional $\alpha-\Omega$-dynamo model with meridional circulation that exhibits typical features of the solar dynamo, including a Hale cycle period of around 20 years and a reasonable shape of the butterfly diagram. With regard to recent ideas of a tidal synchronization of the solar cycle, we complement this model by an additional time-periodic $\alpha$-term that is localized in the tachocline region. It is shown that amplitudes of some dm/s are sufficient for this $\alpha$-term to become capable of entraining the underlying dynamo. We argue that such amplitudes of $\alpha$ may indeed be realistic, since velocities in the range of m/s are reachable, e.g., for tidally excited magneto-Rossby waves.

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M. Klevs, F. Stefani, L. Jouve. 2023-01-13. A synchronized two-dimensional $\alpha-\Omega$ model of the solar dynamo. https://doi.org/10.1007/s11207-023-02173-y

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