Typical decay rate σ for gravity and Rossby and Kelvin waves as a function of (top) τ_drag for τ_rad= 0.3 and (bottom) τ_rad for τ_drag = 20. The lines are values obtained using Eqs. (40), (50) while crosses are results from seven ECLIPS3D calculations.As τ_rad is not constant with depth in the ECLIPS3D results, we have chosen to use an arbitrary value of τ_rad = 0.3 for comparison. However, when τ_drag increasesthe location where the wave exhibits its maximum perturbation, it moves to higher pressures which should correspond to an increase in the equivalent τ_rad. For the Rossby waves, the low τ_drag limit has not been studied numerically as it is irrelevant for superrotation. Kelvin waves of comparable height with Rossby and gravity waves are only clearly identified in four ECLIPS3D calculations.