Collaborative Research: Modeling the Nonlinear Dynamics of Deep Gravity Waves in the Mesosphere and Thermosphere

Global Atmospheric Technologies And Sciences, Inc., Newport News VA

Investigators

Abstract

Gravity Waves (GW) in the Earth's atmosphere exhibit highly diverse dynamics and they have multiple effects throughout the atmosphere. These waves are believed to be the main driver of the Mesosphere and Lower Atmosphere (MLT) region, which is why they are a subject of active research and debate by the Aeronomy community in the U.S. The GW also influence a wide range of other physical processes ranging from tidal and planetary wave structures and dynamics to minor species transport and plasma dynamics in the ionosphere. Therefore, the need to describe such effects accurately also has broader implications for modeling climate variations, responses to variable solar forcing, and space weather, among others. The main purpose of this three-year project is to investigate in great detail the three-dimensional structure and dynamics of GW by means of state-of-the-art numerical simulations. The research project will also provide a significant research opportunity for a graduate student in Aeronomy. The research and EPO agenda of this project supports the Strategic Goals of the AGS Division in discovery, learning, diversity, and interdisciplinary research. It is well established that GW play an important role throughout the upper atmosphere of the Earth. These waves, however, are very difficult to model directly due to their small spatial scales. That leads to the use of GW parameterization in global models. This three-year project will utilize a finite-volume simulation code to solve the compressible, or an-elastic three-dimensional non-linear Navier-Stokes equations in simulations of GW. The project team will investigate numerically the following critical scientific questions: (i) how does GW's spatial and temporal distribution influence GW's self-acceleration instability, dissipation, mean forcing, and penetration to thermosphere ionosphere?; (ii) what role do wave-wave interactions, mean wind, and stability play in GW evolution?; and, (iii) what are the key dynamics in GW-tidal interactions influencing MLT and Thermosphere-Ionosphere dynamics? This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.