| The three major types of oscillations in the atmosphere are gravity waves, planetary waves, and tides. Identifying planetary waves and tides in nighttime-only lidar data is a challenge. The Lomb-Scargle method offers a possible solution to this problem, although aliasing is still a problem when tides are present in the data. The method has been applied to mesospheric Rayleigh-scatter lidar temperature data taken at the Utah State University Atmospheric Lidar Observatory (ALO). This analysis is greatly enhanced by the length and completeness of the data set available through ALO, especially with regard to the identification of planetary waves.; The data analyzed are in seven sets from five different months. This gives a good sampling of each season, with the possible exception of winter. All three types of waves have been identified in the data. The results agree with predictions of seasonal variations in gravity and planetary wave activity. There are two examples of possible wave-wave interactions and/or filtering of tides by the mesospheric jet. |
