Comprehensive Study on Tropical (10°N-15°N) Mesospheric Inversion Layers Using Lidar and Satellite (Timed-Saber) Observations

Abstract

One of the interesting and poorly understood features of mesosphere and lower thermosphere (MLT) region is the phenomenon of Mesospheric Inversion Layers (MILs). The poor understanding of MILs is due to limited access of their occurrence height region, however the lidars are more efficient tools which provide stratosphere and mesosphere nocturnal temperatures with high temporal and vertical resolutions. The state-of-the-art lidar system comprising Mie, Rayleigh lidars installed at National Atmospheric Research Laboratory (NARL), Gadanki (13.5°N, 79.2°E), India has provided an excellent opportunity to undertake this study. The Nd:YAG laser source with lower power (11W) has been replaced by the one with higher power (30W) in January 2007. As the laser power has been increased, the molecular back scatter signal is also increased and consequently the top height level of the temperature retrieval has been increased to ~90-95 km. In the present study, the role of dominant causative mechanisms for the occurrence of MILs has been discussed using mainly the lidar and satellite (TIMED-SABER) observations over Gadanki region.