Magnetic Cycles and Meridional Circulation in Global Models of Solar Convection

TL;DR

This paper reviews recent advances in global solar convection models, highlighting cyclic magnetic activity and improved meridional circulation simulations that reveal organized flow patterns and magnetic reversals.

Contribution

It presents new insights into solar magnetic cycles and meridional circulation maintenance from high-resolution global simulations, enhancing understanding of solar dynamo processes.

Findings

Magnetic activity exhibits polarity reversals with 6-15 year cycles.

Meridional circulation is dominated by a single cell per hemisphere.

Simulations show more coherent and realistic flow patterns.

Abstract

We review recent insights into the dynamics of the solar convection zone obtained from global numerical simulations, focusing on two recent developments in particular. The first is quasi-cyclic magnetic activity in a long-duration dynamo simulation. Although mean fields comprise only a few percent of the total magnetic energy they exhibit remarkable order, with multiple polarity reversals and systematic variability on time scales of 6-15 years. The second development concerns the maintenance of the meridional circulation. Recent high-resolution simulations have captured the subtle nonlinear dynamical balances with more fidelity than previous, more laminar models, yielding more coherent circulation patterns. These patterns are dominated by a single cell in each hemisphere, with poleward and equatorward flow in the upper and lower convection zone respectively. We briefly address the implications of and future of these modeling efforts.