Neutral Density Behavior from 45-90 km Based on Rayleigh Lidar Observations above USU

There are over 900 nights of observations taken by the Rayleigh lidar above Utah State University from 1993 to 2004. The data have been reduced to give absolute temperatures and relative densities in the mesosphere, from 45-90 km (Herron, 2004, 2007). From the 11 years of relative density data an 11-year climatology of mesospheric densities above Logan, Utah has been created. From this climatology I have been able to normalize the 11 years of density data to the following models: the MSISe00 empirical model, the CPC (Climate Prediction Center) reanalysis model, the ERA Interim reanalysis model, and the NASA MERRA reanalysis model. The USU relative density climatology is normalized to the models to show how the models behave when they are extended beyond their upper altitude range. The MSIS empirical model has an extensive altitude and goes far beyond 45 km but was chosen due to its extensive use in the scientific community. The reanalysis models CPC and ERA Interim are near their upper bounds around 48 km, while the MERRA reanalysis model extends slightly higher to 65 km. By interpolation I was able to find their values at 45 km and then normalize the data to their values at 45 km where I am able to find their behavior as are propagated through observed data.