Compensated power spectra computed with on 2D maps for the maps shown in Fig. 5. The upper and lower panels show altitudinal velocity and surface density power spectra, respectively. Each colour corresponds to a different highest resolution of the cells, varying from level 20 down to level 15, which corresponds to a uniform grid. Power spectra in bold and thin lines correspond to the F65 and F10 runs, respectively. The latter are all shifted down by 5 dex for clarity.