ASSESSMENT OF VEHICULAR EMISSION DISPERSION MODELS APPLIED IN STREET CANYONS IN GUANGZHOU, PRC

The applicability of four simple dispersion mathematical models, namel y APRAC, GZE, CALINE4, and PWILG were assessed by comparing the predic ted CO and NOx concentrations with the measured values in street canyo ns in Guangzhou. These simple models were comparatively accurate in pr edicting maximum ground concentration, The accuracy of CO prediction w as much influenced by the assumption of vehicular composition. The unc ertainty of emission sources other than vehicle emissions was an impor tant error source in predicting NOx concentrations.