Calculation of Gravity Wave Altitude Limits due to Diffusion

Friday, 19 December 2014
Stephen Hall and Gary R Swenson, University of Illinois at Urbana Champaign, Urbana, IL, United States
Vertical propagation of atmospheric gravity waves (AGW's) is constrained in the middle atmosphere by diffusion processes. These AGW's are a key component of energy and constituent transfer in this region, but propagation is limited to those altitudes for which the wavelength and period are less than the time and distance scales of the diffusion of those constituents. Using the 1976 Standard Atmosphere Model, it is possible to calculate these diffusion scales and thereby determine the propagation altitude limit of these AGW's based on their period and wavelength. This theoretical study should provide a method for better understanding energy transfer in this region of the atmosphere.