Viscous (in blue) and thermal (in red) dissipation spectra in a uniformly stably stratified medium with throughout the domain in the case of periodic (left) and rigid (right) boundary conditions. Left panel: resonant peak centred on the single gravito-inertial mode that is resonant with the forcing, with frequency given by Eq. (40). Right panel: rigid boundary conditions do not perfectly excite only a single global mode, they instead excite many modes that match the roots of the dispersion relation of gravito-inertial waves when k_z = nπ, for n = {1, …20}.