Reestablishing Observations throughout the Mesosphere with the ALO-USU Rayleigh-Scatter Lidar

In the last few years, the Rayleigh-scatter lidar at the Atmospheric Lidar Observatory at Utah State University (ALO-USU; 41.74° N, 111.81° W) has been upgraded to extend observations from 70 km up to 115 km. This project describes a student project to build and use a complementary Rayleigh-scatter lidar to go from 40 to 90 km, from the upper stratosphere to the upper mesosphere. At the upper end, this new lidar overlaps with the high-altitude lidar. This was done in a period of just over two months. This lidar shares the same lasers, but introduces a 44-cm mirror and a new telescope for the lower altitude observations. The rest of the detector chain is modelled after the one used in the larger lidar. This small lidar will provide a ground-based way of remote sensing the upper stratosphere and mesosphere. Combined with the existing larger lidar, the entire system, covering 40 to 115 km, will provide continuous observations well up into the lower thermosphere. This combined system gives the greatest coverage of any Rayleigh lidar in the world