KE spectra. Snapshots of the KE (u²/2 + v²/2) spectra in all simulations. The blue line shows the simulated KE spectrum. The green, red, and black dashed lines indicate the theoretical slopes of −3, −5/3, and −5, respectively. The transition wavenumbers n_e and n_β are indicated by the intersections of the green and red lines, and the red and black lines, respectively.