Profiles of shock strength. Dots represent the measurements from our numerical simulations: three different amplitudes (200, 100, 50 kms^-1) in magenta, green and blue respectively for each wavelength families represented by their common asymptote Eq. (7) for the three wavelengths (λ₀ = 0.05 L, 0.1 L, 0.2 L in solid lines in red, magenta and black respectively). Also plotted are the predictions from Eq. (6) in black dashed lines.