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

TL;DR

This paper enhances the solar dynamo model by introducing a time-periodic alpha-term in the tachocline, demonstrating that tidal forces could synchronize the solar cycle through realistic velocity amplitudes.

Contribution

It combines a conventional alpha-omega dynamo with a tidal synchronization mechanism via a localized periodic alpha-term, showing potential for entrainment of the solar cycle.

Findings

Periodic alpha-term can entrain the dynamo at realistic amplitudes

Tidal forces may influence the solar cycle timing

Model reproduces key features of the solar cycle

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.