F3 riblet evolution of the parameters obtained from the profiles fitted to a single Gaussian curve. The distributions show the fitted amplitude, Doppler shifts, and broadening from (a)–(c), respectively. In all panels, the green background represents the distribution with respect to time. The mode, mean, and median of each distribution per timestep are shown as red, cyan, and pink curves, respectively. The white columns represent frames that were disregarded due to worse seeing. Bins with a contribution less than 1/100 of the maximum bin are coloured in white. The two short vertical black lines at Δt = 3.4 min mark the timestep with the highest number of pixels identified as riblets. The distribution of the fitted parameters of this timestep is shown in Fig. 10.