We report Rayleigh Density and Temperature Lidar (RDTL) measurements of gravity waves activity in the 40-80 km region at Chatanika, Alaska (650N, 1470 W). We use density profiles measured by the lidar to characterize gravity wave fluctuations. We consider both ensemble of waves as well as monochromatic waves. We present the wave activity from 76 nights in terms of specific potential energy over 10 km altitude ranges from 40 to 75 km. We find that the wave activity in winter 2018-2019 is reduced relative to the other winters. We discuss the propagation of wave energy with altitude. We analyze the correlation between gravity wave activity obtained from RDTL and horizontal winds. We also characterize the wave activity in terms of monochromatic waves. Furthermore, these waves are characterized in terms of vertical wavelength and time period from 51 nights where the observations length exceeded 8 hrs. We find waves with periods between X and Y hours, and vertical wavelengths between Z and W km.
Das et al. (Thu,) studied this question.