  A method for recognizing the types of linear acoustic gravity waves (AGWs) in
the atmosphere from satellite measurements is proposed. It is shown that the
polarization relations between fluctuations of wave parameters (velocity,
density, temperature, and pressure) for freely propagating waves, as well as
evanescent wave modes, differ significantly, which makes it possible to
identify different types of atmospheric waves in experimental data. A
diagnostic diagram is proposed, with the help of which, from the phase shifts
of the observed parameters, it is possible to determine the type of wave, as
well as the direction of its movement relative to the vertical. Using phase
shifts between fluctuations of the velocity and thermodynamic parameters of the
atmosphere, not only the type of the wave, but also its spectral
characteristics can be determined. The verification of the proposed method for
identification of polar wave disturbances in measurements from the low-orbit
satellite Dynamics Explorer 2 was carried out. The verification showed that the
polarization relations of AGW in the thermosphere mainly correspond to the
gravity branch of acoustic-gravity waves freely propagating in the direction
from bottom to top. This conclusion is consistent with other results of AGW
observations in the atmosphere and ionosphere by ground-based and satellite
methods. No evanescent waves were observed on the considered orbits.
