Scales of linear baroclinic instability and atmospheric macroturbulence

A normal mode baroclinic instability analysis is performed for the mean states of a wide range of atmospheric circulations in a dry general circulation model. The meridional and zonal scales of the normal modes are compared to those of the energy-containing eddies in the corresponding nonlinear simulations. The range of simulated circulations includes circulations with multiple jets, so that the meridional structure of the linear waves can be compared to the equilibrated mean jet structure. Theory suggests that the inverse cascade of energy is confined to scales smaller than the scale of the linearly most unstable baroclinic waves and this prediction is explicity tested.