ALOHA-93 MEASUREMENTS OF INTRINSIC AGW CHARACTERISTICS USING AIRBORNEAIRGLOW IMAGER AND GROUNDBASED NA WIND TEMPERATURE LIDAR/

Monochromatic Acoustic Gravity Waves (AGWs) with periods < 1 hour are a prevalent feature in the mesospheric airglow layers. These waves are important dynamically and energetically to the region where their tem poral and spatial morphology are not well established. The purpose of this study is establish the intrinsic AGW characteristics over an exte nded region (as flown by the NCAR Electra aircraft) and to present the data in terms of the predicted spectral domain defined by the Brunt-V aisala frequency and the diffusive filtering limit proposed by Gardner [1994]. On October 21, 1993, observations were made from the NCAR Ele ctra aircraft during a 6 hour flight in a large triangle N and W of Ma ui, for a integral distance of similar to 3000 km. The entire area obs erved [similar to 1 M km(2)] had a monochromatic AGW propagating towar d the NW and the western half had a SW propagating wave superimposed. These waves were also observed with the Michelson interferometer on th e aircraft and an airglow imager at the Haleakala location during this time. Intrinsic phase velocities were computed where the Na Wind/Temp erature (W/T) lidar at Haleakala provided a measure of the mean wind t o compensate phase velocities observed with the imager. The data were tabulated and plotted in an AGW spectral reference frame and compared to cutoff conditions predicted by diffusive filtering theory.