Gravity Wave Behavior Associated With Strong Convective Activities During Tropical Cyclone Aila

Abstract

Atmospheric gravity waves are generated by the interplay of earth s gravity and buoyancy effect on an air parcel. The zonal and meridional wind and temperature perturbation observed in the troposphere and stratosphere exhibits signature of gravity waves. The seasonal analysis of gravity wave activity has been made for the present tropical location, Kolkata $(22.5726^{\\circ}\\mathrm{N}, 88.3639^{\\circ}\\mathrm{E})$ using radiosonde data. Gravity wave generated due to intense tropical cyclone Aila has been investigated using COSMIC radio occultation data over the Indian region. The gravity wave energy calculated from temperature profile perturbations shows a significant enhancement during the cyclone which is accompanied by a low outgoing long wave radiation (OLR) indicating the presence of strong convective activities. An intrusion of water vapor into the lower stratosphere over the cyclone affected region is detected from Stratosphere-troposphere Processes And their Role in Climate data (SPARC).