on Ozone via Changes in the Brewer–Dobson Circulation

Abstract

In this short note, the effect of enhanced circulation due to doublingCO(2) on ozone is investigated. The difference of Brewer-Dobsoncirculation (BDC) between the doubled CO(2) and control run from anidealized atmospheric general circulation model is added to the BDCclimatology derived from National Centers for EnvironmentalPrediction-Department of Energy Reanalysis 2 (NCEP2) from 1979 to 2002.Then it is used to drive the California Institute of Technology/JetPropulsion Laboratory (Caltech/JPL) two-dimensional chemistry andtransport model. The results reveal that the total ozone increases by 7and 3.5 Dobson units (DU) in the high latitudes of the Northern andSouthern Hemispheres, respectively, and decreases by 4 DU in the Tropicsas a result of the increase in BDC associated with doubled CO(2). If thechange of eddy mixing coefficients after doubling CO(2) is alsoconsidered, the total ozone will increase by 6.5 and 3 DU in the highlatitudes of the Northern and Southern Hemispheres after combining botheffects from the change in BDC and eddy mixing coefficients.