One obvious feature of the solar cycle is its variation from one cycle to another. In this article,
we review the dynamo models for the long-term variations of the solar cycle. By long-term …

The dynamic activity of the Sun—sustained by a magnetohydrodynamic dynamo mechanism
working in its interior—modulates the electromagnetic, particulate, and radiative …

Solar activity has a cyclic nature with the≈ 11-year Schwabe cycle dominating its variability
on the interannual timescale. However, solar cycles are significantly modulated in length …

The Sun's magnetic field is the engine and energy source driving all phenomena collectively
defining solar activity, which in turn structures the whole heliosphere and significantly …

The Sun's activity cycle governs the radiation, particle and magnetic flux in the heliosphere
creating hazardous space weather. Decadal-scale variations define space climate and force …

The dynamic activity of stars such as the Sun influences (exo) planetary space environments
through modulation of stellar radiation, plasma wind, particle and magnetic fluxes. Energetic …

The most widely accepted model of the solar cycle is the flux transport dynamo model. This
model evolved out of the traditional α Ω dynamo model which was first developed at a time …

Aims. Cosmogenic isotopes provide the only quantitative proxy for analyzing the long-term
solar variability over a centennial timescale. While essential progress has been achieved in …

This paper reviews recent advances and current debates in modeling the solar cycle as a
hydromagnetic dynamo process. Emphasis is placed on (relatively) simple dynamo models …

Aims. Although the time of the Maunder minimum (1645–1715) is widely known as a period
of extremely low solar activity, it is still being debated whether solar activity during that …