Abstract

The Parametric Generation of Magnetic-Acoustic-Gravity Waves in an Atmosphere

M.Petukhov (Nizhny Novgorod State University, Nizhny Novgorod, Russia); Yu.V.Petukhov (Institute of Applied Physics of RAS, Nizhny Novgorod, Russia)

e-mail: petukhov@hydro.appl.sci-nnov.ru

Based on a plane isothermal atmosphere model with the inhomogeneous magnetic field oriented in the perpendicular direction to the gravity acceleration, for vertically propagating disturbances the parametric generation of magnetic-acoustic-gravity (MAG) waves is investigated. Both nonpropagating and propagating MAG waves are shown to be generated at the difference frequency via the nonlinear interaction of primary waves in the frequency range "forbidden" for propagation of MAG waves during their linear generation. An acoustic wind has been found to be formed in the isothermal atmosphere at zero difference frequency; its magnitude and orientation essentially depends on difference of initial phases of atmosphere lower boundary oscillations. Nonlinear generation of MAG waves at the difference and total frequencies via the interaction between primary nonpropagating disturbances and propagating waves is considered. [This research was supported by the RBFR 02-02-17374 grant].

Section : 6