Time-frequency analysis of lidar signal to obtain gravity waves characteristics

The Lidar is a laser beam which sent vertically monochromatic pulses in the atmosphere. The analysis of the backscattered light provides information about the vertical temperature evolution versus height. Temperature perturbations are associated with gravity waves phenomenon which play a major role in the middle atmosphere dynamics. The aim of the study is to identify characteristics of these particular waves above Reunion island with an usual parametric time-frequency tool. A comparison is made for two representative periods.