Figure 6From: Associations between ozone and morbidity using the Spatial Synoptic Classification system Ozone distribution of the seven air masses. (a) The 5-year period 1996-2000 and (b) the 4-year period 2001-2004. Probability (expressed as a percentage) of finding ozone (O3) concentrations above a threshold concentration for a given air mass (P(O3|AM)).Back to article page