AN INVESTIGATION OF INTRINSIC GRAVITY-WAVE SIGNATURES USING COORDINATED LIDAR AND NIGHTGLOW IMAGE MEASUREMENTS

Simultaneous observations of gravity waves using an Na wind/temperatur e lidar and a multi-wavelength all-sky nightglow imager were obtained, for the first time, during the ALOHA-93 campaign. A novel investigati on of intrinsic wave parameters has been made by combining measurement s of the horizontal wave components imaged in four nightglow emissions (height range similar to 80-100 km) with Na lidar soundings of the ho rizontal wind field and temperature profiles over the same height inte rval. On October 19 both instruments registered marked monochromatic w ave motions. The intrinsic periods of several of these waves have been determined and were found to vary considerably with altitude, often r esulting in a significant increase over their observed wave periods. I t is shown that these two instrumental techniques generally sampled di fferent regions of the gravity wave spectrum: the lidar exhibiting mos t sensitivity to short vertical wavelength waves (less than about 10 k m) while the imager was most responsive to larger vertical wave-length waves. This study illustrates the significant advantages of combining wind/temperature lidar and multi-wavelength image observations for in trinsic gravity wave measurements.