Recent Advances on Solar Global Magnetism and Variability
Abstract
We discuss recent observational, theoretical and numerical progress made in understanding the solar global magnetism and its short and long term variability. We discuss the physical process thought to be at the origin of the solar magnetic field and its 22-yr cycle, namely dynamo action, and the nonlinear interplay between convection, rotation, radiation and magnetic field, yielding modulations of the solar constant or of the large scale flows such as the torsional oscillations. We also discuss the role of the field parity and dynamo families in explaining the complex multipolar structure of the solar global magnetic field. We then present some key MHD processes acting in the deep radiative interior and discuss the probable topology of a primordial field there. Finally we summarize how helioseismology has contributed to these recent advances and how it could contribute to resolving current unsolved problems in solar global dynamics and magnetism.