Ca ii-iii ionisation fraction (left column, solid line, left axis), gas temperature (left column, dot-dashed line, right axis), and normalised rates (right column) as a function of column mass for four time steps (rows from top to bottom) in the dynamic simulation. The rates for the radiative transitions from the bound levels 1−5 to the continuum (i = 6, abbreviated “c”) are divided by the total Ca number densities. Positive rates indicate ionisation, negative rates recombination. The sum of all radiative b-f transitions is represented by the thick solid line. The gas temperature is repeated in the right column as reference (dot-dashed line). The height axis for the individual time step is shown at the top of each panel. Please note the different data ranges for the individual time steps.