Correction to modelling of the influence of aerosol processes for the dispersion of vehicular exhaust plumes in street environment

A paper that was previously published in Atmospheric Environment [Pohjola et al., 2003. Modelling of the influence of aerosol processes for the dispersion of vehicular exhaust plumes in street environment. Atmospheric Environment 37(3), 339–351.] contained a description of the properties of particulate matter in exhaust emissions and in urban background air. This data contained particle number concentrations and particle masses for four size classes. The mass and number concentrations of particulate matter exhaust emissions were computed correctly. However, a subsequent checking has shown that the values of particle masses of urban background air that were used in the numerical computations were one to two orders of magnitude too small, in relation to the corresponding particle number concentrations of urban background air. This has affected the numerical results on particle sizes, and produced an erroneous temporally decreasing particle size in some cases; this is notable particularly for the Aitken mode. The calculations have therefore been repeated, replacing the erroneous data with the correct data. However, the main conclusions drawn by Pohjola et al. (2003) are shown still to be valid, using the corrected input data.