The analyses of sunspot observations revealed a fundamental magnetic property of the umbral boundary, the invariance of the vertical component of the magnetic field.

While the quiet Sun magnetic field shows only little variation with the solar cycle, long-term variations cannot be completely ruled out from first principles.

Recent numerical simulations and observations of sunspots show a significant amount of opposite polarity magnetic fields within the sunspot penumbra. Most of the opposite polarity fields are associated with convective downflows.

Solar magnetic activity exhibits variations with periods between 1.5–4 years, the so-called quasi-biennial oscillations (QBOs), in addition to the well-known 11-year Schwabe cycles. The solar dynamo is thought to be the responsible mechanism for the generation of the QBOs.

Recently, the radiative magnetohydrodynamic (R-MHD) code MURaM was extended to include the corona. The code was used to simulate a bipolar active region with additional parasitic flux emergence near one of the sunspots that produced a flare.

The motions of small-scale magnetic flux elements in the solar photosphere can provide some measure of the Lagrangian properties of the convective flow.

There have been a number of reports in the literature of counter-Evershed flows in well developed sunspot penumbrae, i.e. flows directed towards the umbra.

Magnetic field amplification in exploding granules and the role of deep and shallow recirculation

We aim to investigate the nature and occurrence characteristics of grand solar minimum and maximum periods, which are observed in the solar proxy records such as 10Be and 14C, using a fully non-linear Babcock-Leighton type flux transport dynamo including momentum and entropy equations.