Potential ozone production following convective transport based on future emission scenarios

Current and projected (up to 2050 A.D.) concentrations of boundary layer trace gases, including NOx, CO, CH4, and several nonmethane hydrocarbons were redistributed throughout the troposphere in a simulation of a central U.S. squall line using the Goddard Cumulus Ensemble (GCE) convective cloud model. Vertical profiles of the redistributed trace gases were used in a one-dimensional photochemical model to determine the vertical profile of the potential production of 03. Several different emission scenarios were considered. In the case where NOx emissions were doubled along with an increase in CO, CH4, and NMHCʹs, the middle troposphere showed an enhancement of 41% for O3 production relative to the 1985 case. For the reduction scenario, where NOx emissions were decreased by a factor of two, the O3 produced in the middle troposphere was reduced by 50%. Given the role of convection in the regional O3 budget of the central U.S. during the summertime, our results suggest that substantial changes in emissions could bring about changes in mid-tropospheric O3 large enough to be observed by satellite remote sensing.