The irregularities of the sunspot cycle and their theoretical modelling

Abstract

The 11-year sunspot cycle has many irregularities, the most promi- nent amongst them being the grand minima when sunspots may not be seen for several cycles. After summarizing the relevant observational data about the irregularities, we introduce the flux transport dynamo model, the currently most successful theoretical model for explaining the 11-year sunspot cycle. Then we analyze the respective roles of nonlinearities and random fluctuations in creating the irregularities. We also discuss how it has recently been realized that the fluctuations in meridional circula- tion also can be a source of irregularities. We end by pointing out that fluctuations in the poloidal field generation and fluctuations in meridional circulation together can explain the occurrences of grand minima.

Invited paper for the C.V. Raman 125th birth anniversary issue of Indian Journal of Physics

References in corpus (6)

• Predicting solar cycle 24 with a solar dynamo model
• Solar activity forecast with a dynamo model
• Exploring the Physical Basis of Solar Cycle Predictions: Flux Transport Dynamics and Persistence of Memory in Advection versus Diffusion Dominated Solar Convection Zones
• Importance of Meridional Circulation in Flux Transport Dynamo: The Possibility of a Maunder-like Grand Minimum
• Turbulent magnetic pumping in a Babcock-Leighton solar dynamo model
• The Hemispheric Asymmetry of Solar Activity During the Twentieth Century and the Solar Dynamo

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• A theoretical model of the variation of the meridional circulation with the solar cycle
• A Theoretical Model of the Near Surface Shear Layer of the Sun
• A Critical Assessment of the Flux Transport Dynamo
• Flux Transport Dynamo: From Modelling Irregularities to Making Predictions
• Surface Flux Transport Modeling using Physics Informed Neural Networks
• The Sun's polar magnetic field: datasets, proxies and theoretical issues
• Predicting a solar cycle before its onset using a flux transport dynamo model