Time evolution of |B| on a vertical cut through the center of the domain along the x-axis. The first two snapshots show the subsurface field evolution prior the appearance of flux in the photosphere, the remaining six snapshots correspond to the photospheric magnetograms shown in Figure 1 (except for those at t = 28 and 30 hr).

(An animation and a color version of this figure are available in the online journal.)

The video/animation of this figure is available in the online journal.