The investigators will study the density and temperature structure of the middle atmosphere using two lidars at Utah State University. A Rayleigh scatter lidar will measure temperatures in the altitude range from 30 to 90 km, while a resonance lidar will probe the atmosphere between 80 and 105 km altitude. The existing Rayleigh lidar will be repaired and operated for about 100 hours during the coming winter. The alexandrite lidar, currently being developed, will be deployed and tested. The coordinated observations with co-located optical instruments will allow studies of the dynamics of the middle atmosphere, including gravity waves, neutral winds, and mesospheric inversion layers.***
