Simultaneous observation of dual-site airglow imagers and a sodium temperature-wind lidar,and effect of atmospheric stability on the airglow structure

The heights of horizontal structures in the OH airglow images were observed with two all-sky imagers at Platteville (40.2N, 104.7W) and Yucca Ridge Field Station (40.7N, 104.9W) in Colorado. The sodium temperature-wind lidar of CSU at Fort Collins (40.6N, 105.1W) observed temperature and wind velocities around 80–105-km altitude, providing time-height variations of atmospheric stability. Simultaneous observations with the imagers and the lidar were successful on two nights: November 18 and 19, 2003. The estimated height from OH airglow images were lower (80–86 km) than those observed in Japan, with significant time variation. Comparison with the temperature and wind observed by the lidar showed that the estimated height is likely to coincide with the height of small N² (close to 0) values. Ripples (<10-km horizontal scale) were simultaneously observed in the image.