Studies on gravity waves in the middle atmosphere

Abstract

This work is a contribution towards better understanding of gravity waves in the Earth’s middle atmosphere and their role in vertical coupling of the atmosphere. It is partly an extension of previously known facts and partly a discovery of new facts. The first chapter provides the basic foundation of the thesis by introducing the basic concepts of atmospheric dynamics and an overview of gravity waves. The following chapters describe the original work done by the candidate. This includes nightglow observations of gravity waves from low latitude sites, Panhala and Silchar, to study the morphology and characteristics of gravity waves. We also identified the potential sources of these waves using reverse ray tracing method. Detailed analysis of mesospheric frontal events have also been carried out from low latitude sites in India and the high latitude site, Tromsø, in Norway. The final chapter summarizes the major findings of the thesis and provides a scope for future studies.