Large Scale Atmospheric Variability from a Quasi-Geostrophic Turbulence Perspective

Northwest Research Associates, Incorporated, Seattle WA

Investigators

Abstract

The project will investigate the extent to which variability of the large-scale atmosphere is controlled by variations at the smaller synoptic scales. The upscale energy flux from the synoptic waves is reckoned to be an important contributor in generating variations at the larger scales. It is, of course, by no means the only contributor since instability of the zonal flow, variations in tropical diabatic heating, and planetary wave-zonal flow interactions can also generate significant planetary-scale variability in the troposphere on the intraseasonal-to seasonal time scales. Modeling and prediction of this variability component remains challenging. Drs. Orlando and, co-PI, Dr. Tung (Univ. of Washington, Seattle) will conduct a dynamically oriented analysis of the interaction of upscale synoptic fluxes and the larger-scale tropospheric circulation. The focus of the project will be on characterizing the upscale synoptic fluxes from modeling experiments of varying complexity. The project will advance understanding and modeling of the tropospheric circulation variability on intraseasonal-to-seasonal time scales, particularly, during the Northern winter season.