Time evolution for a selection of volume-averaged quantities, related to the magnetic field, and the evolution of the vertical magnetic field structure, for simulation sg-mhd-G001. First image: volume-averaged magnetic energy densities separated into components (left abscissa) and volume-averaged toroidal field ⟨B_y⟩ (right abscissa). Second image: horizontally averaged toroidal field component ⟨B_y⟩_xy as a function of (z, t).