Gravity waves are well known for deforming the bottom-side plasma of the F region into the wavelike ionization structures which then act as a seed for Rayleigh–Taylor instability, which in turn generates irregularities. The present study features midnight fossil airglow depletions that revived due to ongoing gravity wave (GW) activity and turned into an active depletion.

This study investigates the formation mechanism of a tropopause cirrus cloud layer observed at extremely cold temperatures over Hyderabad in India during the 2017 Asian summer monsoon using balloon-borne sensors. Ice crystals smaller than 50 microns were found in this optically thin cirrus cloud layer. Combined analysis of back-trajectories, satellite, and model data revealed that the formation of this layer was influenced by gravity waves and stratospheric hydration induced by typhoon Hato.

The chemical composition of the stratospheric aerosols collected aboard high-altitude balloons above the summer Asian monsoon reveals the presence of nitrate/nitrite. Using numerical simulations and satellite observations, we found that pollution as well as lightning could explain some of our observations.

The authors have successfully recommissioned an unused tri-axial Helmholtz coil system. The system now serves as a national facility for calibrating magnetometers.