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 solar cycle is reviewed. The 11-year cycle of solar activity is characterized by the rise
and fall in the numbers and surface area of sunspots. A number of other solar activity …

The evolution of active regions (AR) from their emergence through their long decay process
is of fundamental importance in solar physics. Since large-scale flux is generated by the …

It has been a prevailing picture that active regions on the solar surface originate from a
strong toroidal magnetic field stored in the overshoot region at the base of the solar …

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 …

Strong solar flares and coronal mass ejections, here defined not only as the bursts of
electromagnetic radiation but as the entire process in which magnetic energy is released …

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 …

Sunspots and the plethora of other phenomena occurring in the course of the 11-year cycle
of solar activity are a consequence of the emergence of magnetic flux at the solar surface …

The prediction of the strength of an upcoming solar cycle has been a long-standing
challenge in the field of solar physics. The inherent stochastic nature of the underlying solar …

We report the results of a magnetohydrodynamic (MHD) simulation of a convective dynamo
in a model solar convective envelope driven by the solar radiative diffusive heat flux. The …