Transport Dynamics in the Stratosphere

Johns Hopkins University, Baltimore MD

Investigators

Abstract

The goal of this project is to use a two-dimensional (latitude-height) chemical-dynamical model to investigate the reasons for wide variations in the mean-age of stratospheric air in model simulations. The mean-age conveys information about the parcel transport time scales in the lower stratosphere in the presence of diffusion, when photochemical processes occur along parcel trajectories. The impact of horizontal mixing, stratospheric oscillations (quasi-biennial and semi-annual), and mesospheric photochemical destruction on the mean-age of stratospheric air will be examined. Dr. Zhu's theoretical and modeling analysis will help clarify the physical and mathematical basis for the age-of-air concept, and lead to its more accurate estimation. The Large-scale Dynamic Meteorology Program funds this award.