Maps of the two snapshots analyzed in detail (top, S0; bottom, S1). From left to right: continuum intensity at 6300 Å, temperature, magnitude of the horizontal velocity in units of the local sound speed, and total magnetic field strength at the log τ₅₀₀₀ = −1 surface. Contours show the projection on the horizontal plane of cells containing supersonic flows (red specifies flows that are nearly horizontal 120° > γ > 60° and; yellow nearly vertical flows 180° > γ > 150° and 30° > γ > 0°; orange flows with inclinations 150° > γ > 120° and 60° > γ > 30°. The four numbered markers point to selected events discussed in detail in Sect. 3.2.