title: Trends in meteorologically adjusted ozone concentrations in six Kentucky metro areas, 1998-2002.
abstract: Meteorologically adjusted ozone (O3) concentrations during five recent O3 seasons (1998-2002) were computed for six Kentucky metro areas using a nonlinear regression model originally developed for forecasting ground-level O3 concentrations. The meteorological adjustment procedure was based on modifying actual measured O3 concentrations according to model-predicted responses to climate departures with respect to a reference year. For all six Kentucky metro areas, meteorologically adjusted O3 concentrations declined over the five-year period. The linear best-fit rate of decline in mean adjusted O3 concentrations ranged from 0.9 to 2.6 ppb/yr for these metro areas; the average rate of decline was 1.6 ppb/yr. The rates of decline in meteorologically adjusted extreme value (e.g., 95th percentile) concentrations were approximately the same, but there is greater statistical uncertainty concerning the extreme value trends.
authors.affiliation: Department of Mechanical Engineering, J.B. Speed School of Engineering, University of Louisville, KY 40292, USA. geoffrey@louisville.edu
authors.forename: W Geoffrey
authors.initials: WG
authors.lastname: Cobourn
authors.forename: Yiqiu
authors.initials: Y
authors.lastname: Lin
mesh_terms: D002947:Cities; D004784:Environmental Monitoring; D005544:Forecasting; D007629:Kentucky; D008685:Meteorological Concepts; D008962:Models, Theoretical; D010083:Oxidants, Photochemical / Q000032:analysis*; D010126:Ozone / Q000032:analysis*
chemical_list: D010083:Oxidants, Photochemical; D010126:Ozone