PREDICTING TRAFFIC-GENERATED CARBON-DIOXIDE - CONCENTRATIONS IN SYDNEY

The abilities of two line-source dispersion models to predict road-edg e concentrations of carbon dioxide along several roads are tested. The comparison of the predicted CO2 concentrations from both CALINE4 and HIWAY-2 using a new power-based emissions module are compared with eig ht days of experimental data collected at three sites in Sydney throug h a recent held study carried out by the Commonwealth Scientific Indus trial Research Organization (CSIRO) on behalf of the Road and Traffic Authority (RTA) in Sydney to quantify air pollution near roads and hig hways in Sydney. The measurements were made at locations up to 60 m do wnwind from the roadside and to heights 10 m above the ground; The com parison of the measured CO2 concentrations and those predicted on the basis of appropriate traffic and meteorological data shows that both C ALINE4 and HIWAY-2 when used in conjunction with the new vehicle emiss ions module, satisfactorily estimate road-edge concentrations of CO2. As such, both the two dispersion models, CALINE4 and HIWAY-2, in conju nction with the new power-based emissions module, are potentially usef ul tools for highway planners.