Keywords: climate change, ozone concentrations, air pollution, health hazards, modelling, air quality
Statistical approach to estimate the impact of climate change on daily ozone concentrations
Short–term exposure to ozone is a public health concern worldwide. Surface ozone is a secondary air pollutant, formed primarily through a complex series of photochemical reactions between nitrogen oxides and reactive hydrocarbons. Hot days with clear skies favour ozone production. Hence, a warmer climate is likely to increase ozone ambient concentration and consequently, the impact of ozone–related health effects. In this paper, we present a statistical model that was developed using an additive mixed modelling approach to estimate daily ozone concentrations based on ground level climate variables, ozone precursors and synoptic atmosphere variables from the National Centre of Environmental Prediction. Two future scenarios (A2a and B2a) of daily ozone concentrations were obtained using the global circulation model HadCM3 taking also into account local per capita ozone precursor's emissions and population growth for each scenario. Results showed an overall increasing tendency in both scenarios in the average number of events per year with daily maximum ozone levels between 70 and 90 µg m
–3and a shift in the location of the bimodal seasonal peak.