Three-dimensional visualization of magnetic field line (green) corresponding to the seed point shown as a cyan asterisk in Fig. 1. The horizontal extent corresponds to the region shown in Fig. 1b. Panels a–f correspond to snapshots at every 5 min starting from t = 0 (the same instance as in Fig. 1). The red vertical line corresponds to the initial location of the seed point. Saturated maps of magnetic field strength at the mean solar surface are also shown for each temporal snapshot.