Frequency Characteristics Of Acoustic-Gravity Eigenwaves Of The   Nonadiabatic Atmosphere
  The main objective of the given work consists in the account of the basic mechanisms, which decline processes in atmosphere from adiabaticity approach, and in the study of effect non-adiabaticity on the swing of eigenmodes of atmosphere at various altitudes. The dispersion equation is solved, dispersion curves for acoustic and gravity branches are explored. The increment of growth of eigenmodes at various altitudes of atmosphere is explored. Frequencies (real part) both for acoustic, and for gravity branches acoustic-gravity waves (AGW) in nonadiabatic atmosphere, coinciding with frequencies of the adiabatic model for the same wave vectors at low altitudes, smoothly decrease with altitude. It leads to decrease of a phase velocity for both branches at larger altitudes in a real atmosphere in comparison with predicted by the adiabatic model. 
V.V. Lyahov, V.M. Neshchadim
physics.plasm-ph math-ph math.MP physics.ao-ph