A Simple Method to Estimate Traffic NO_x Emissions from Ambient NO_x Concentrations with a Perfectly Mixing Model

Abstract

It is very important to estimate ambient air concentrations from NO_x emissions, when promoting countermeasures against air pollution. For this purpose, many of diffusion models and statistical models have been put into practical use. Also, it is important to estimate precisely the amount of NO_x emissions over a local area. However, the methods which have been currently used are very complicated. Then, much xnan-power and many sorts of datas are necessary to estimate the amount of NO_x emissions.
Therefore we studied a simple method tentatively to calculate traffic NO_x emissions from processing concentration datas at a monitoring site for traffic air pollution.
In this study, 2 monitoring stations in Osaka prefectural area were selected and a ventilation model with perfect mixing was used to relate the amount of NO_x emissions from traffic and the concentrations on these monitoring stations. On the other hand, the amount of NO_x emissions was estimated from the both of traffics and NO_x emission factors or automobiles with using a q-v model relating traffics and driving speed. Then the parameters in the model were determined in the two cases and the applicability of this ventilation model was examined with these parameters. As a result of this study we got hih correlation coefficients related between teh NO_x emissions calculated from the ambient air concentrations and those calculated from NO_x emission factors and the traffics. It is considered possible in this study to estimate the amount of NO_x emissions from traffics with the simple method.