A street canyon model for estimating NOx concentrations due to road traffic

This paper focuses on the development of a dispersion model aimed at forecasting nitrogen oxides (NOx) concentrations due to vehicular traffic within a street canyon. Experimental data measured in Firenze (Italy) were analyzed in order to recognize independent variables to be used in the model. The latter takes into account both emission processes from road vehicles and overall photochemical phenomena driven by solar radiation through a semi-empirical approach. A calibration of basic dispersion formulas was performed by using field data. NO, model performances showed a precision degree comparable with respect to analogue semi-empirical models currently used to forecast inert pollutant levels in urban areas. The two authors have contributed in equal parts to the work described in this paper.