Evolution of the volume-averaged buoyancy power in 3D MTI with whistler suppression. To the left of the vertical dotted line the runs have no additional external forcing, which is turned on at t = 0. The buoyancy power is normalized to , the MTI energy injection rate (PL22a). The 3D runs shown are the same as in Fig. 2. Despite strong whistler suppression, the system remains buoyantly unstable thanks to external forcing.