Temporal evolution of the magnetic field strength |B| (solid black lines), LOS velocity v_LOS (dashed blue lines) and temperature LOS changes ∇_LOST (dot-dashed red lines) at three different log τ₅₀₀ values estimated from SIR inversions of the Fe I 617.3 nm profiles. First column: Results from the spatial average of the full area of the MBP (region marked by the purple contour in the first column of Fig. 2). Second column: Results from the spatial average of the MBP core (region marked by the black contour in the first column of Fig. 2). The shaded areas represent the standard deviation as a statistical error for each curve. The legends shown in the first row of plots apply to all plots.