In an effort to determine cost-effective emission control strategies to reduce surface ozone concentrations in Europe, an integrated assessment model for boundary layer ozone is being developed at IIASA. In its current version, the ozone formation and transport module of this integrated assessment model predicts ozone mixing ratios based on annual emissions of nitrogen oxides and volatile organic compounds, both of which play major roles in the ozone problem. One source of ozone that is not currently included as an explicit predictor within this model, however, is the transport of ozone and its precursors from the free troposphere to the boundary layer.
The purpose of this paper is to study the influence of the free troposphere on boundary layer ozone mixing ratios and to determine whether or not this free tropospheric influence is significant enough to be included in the model
