Horizontal averages of the Bifrost simulation. The magnetic pressures (P_B) are given in dyn/cm² for the QS simulation before the ramp at snapshot 1000 (dashed green), for the time-independent LFFF (dashed red), and for the simulation after the ramp at snapshot 1120 (dashed purple). The pressure (orange), the density (light blue), and the temperature (dark blue) of the atmosphere are plotted at snapshot 1000. The density is given in g/cm³, multiplied with a factor 10¹² to fit on the same axis as the magnetic pressures, while the temperature is given on the right axis. The shaded gray area (z ∈ [0, −1] Mm) represents the “thick” photosphere, up to the altitude of the temperature minimum, i.e., the height where the density stratification is the strongest (see Sect. 3.4 for more details).