## Nonadiabatic magneto-acoustic-gravity waves in a stratified atmosphere.(Russian. English summary)Zbl 0846.76097

Summary: A theory of propagation of nonadiabatic magneto-hydrodynamic waves in a compressible, conducting, and vertically stratified atmosphere in the presence of an inclined magnetic field and gravity force is developed. The nonadiabaticity of oscillations is due to radiative heat exchange. Optically thin perturbations are analyzed whose heat exchange function follows the Newton cooling law. The equations of magnetic hydrodynamics are solved analytically in the case of oblique propagation of waves with respect to the magnetic field. The solutions obtained are expressed in terms of the generalized Meijer’s hypergeometric $$G$$-functions, which describe oscillations with arbitrary frequency and wavelength at any level in the isothermal atmosphere. The dispersion properties of the adiabatic magneto-acoustic-gravity waves are analyzed, and the decrements and damping wave-lengths of oscillations in the regions of strong and weak magnetic fields are derived. The analytical solutions obtained can be used to construct a theory of linear transformation of nonadiabatic magneto-acoustic-gravity waves in the isothermal atmosphere.

### MSC:

 76W05 Magnetohydrodynamics and electrohydrodynamics 86A10 Meteorology and atmospheric physics