Using the altitude profiles of temperature fluctuations obtained from Rayleigh Lidar observations at Gadanki
(13.5°N, 79.2°E), India, the characteristics of gravity waves were studied. For this study the temperature profiles on 30
nights during January to March 1999 and 21 nights during February 2000 in the 27-65 km altitude region are used. The
gravity wave perturbations showed periodicities in the 0.5 - 3 hours range and attain large amplitudes ~8 K in the
mesosphere. The phase profiles shows downward propagation indicating the upward wave energy propagation with a
vertical wavelength of 5-7 km. The vertical profile of potential energy per unit mass are computed from the temperature
fluctuations. The observed energy growth is less than the theoretically expected energy growth, which indicates that the
wave is getting damped. The percentage of dissipation of prominent periodicities of gravity waves is calculated at
various height levels. It is observed that gravity waves are dissipated more in mesosphere than in stratosphere. The day
to day variability of prominent periodicities are studied.
Altitude profiles of middle atmospheric temperature data using Rayleigh Lidar at Gadanki have been utilized to study the
gravity wave characteristics. The wave activity during the period November 2002-April 2005 is investigated. The
vertical propagation characteristics show waves with maximum amplitude of ~5-8 K and vertical wavelength of ~10 km.
Potential energy density of these two bands of periodicities in the altitude regions 30-60 km is estimated for different
seasons. Equinoctial enhancement in the wave activity is observed. Momentum fluxes of these two bands of periodicities
of gravity waves also exhibit seasonal variation with maximum around equinox and minimum in solstial months. A high
correlation exists between the gravity wave activity and one of its major sources namely convection.