Atmosphere Explorer measurements of neutral wind, temperature, and composition are used to determine the characteristics of atmospheric gravity waves. Wind (horizontal or vertical component) and temperature data for N2 and composition data for O, N2 and He are filtered to separate the wave information from the gross features. A spectral analysis of the wave data is performed using the Maximum Entropy Method (MEM) to calculate wave amplitude, phase, and coherence at different Doppler shifted frequencies. An atmospheric wave is identified when a strong peak is observed in the auto-power and cross-power spectra at the same Doppler shifted frequency for all of the wave quantities (wind, temperature, and composition). We derived the dispersion relation and polarization relations for two specie gravity waves in an isothermal, horizontally stratified atmosphere (without dissipation) which are fit to the amplitudes and phases from the spectral analysis to determine the wave parameters &ohgr; and k↘. There is sufficient information in the amplitudes and phases of wind, temperature, and composition to completely specify the period, wavelength and direction of propagation. It is found that the theoretical wave amplitudes and phases are not significantly modified with the neglect of heat conduction, viscosity and ion drag. |