Two snapshots of the emergence run − side view of the simulation domain at t = 0 s (upper) and t = 188 s. The vertical plane shows the magnetic field strength. The direction of the introduced horizontal field is shown with red arrows (+X direction). The green isosurface of a temperature of 6000 K marks the position of the τ₅₀₀ ≈ 1 level. Above this corrugated plane, green features are visible that signal hot gas in the upper part of the simulation domain. This is where reconnection takes place or shock fronts are formed.