Characteristics and influencing factors of traffic pollutant emission concentration in Shenzhen City

Abstract

With the increasing number of motor vehicles, exhaust pollution has become increasingly serious. In order to grasp the roadside air pollution caused by traffic emissions in Shenzhen City and explore the relationship between traffic and air pollution, we design a series of roadside monitoring experiments to study the law and key influencing factors of traffic emissions in air pollution. The experiments monitor the traffic flow, meteorological data, and air pollutant mass concentration of typical roads. By comparing the monitoring results with those of the national air quality control points, which reflects the impact of road moving sources on air quality, we find that when there is less traffic, the roadside monitoring results are consistent with those of the state control point; when the traffic flow (especially freight) is large, the roadside monitoring results are significantly higher than those of the state control station. Based on the correlation analysis of nitrogen oxide (NOx) mass concentration and carbon monoxide (CO) mass concentration with the main influencing factors, the effects of traffic flow and weather on the mass concentration and trend of pollutants emitted by traffic are revealed. The overall trend is more consistent with the total traffic volume. The results show that the mass concentration of NOx and CO in various districts of Shenzhen are mainly affected by the emissions of motor vehicles (especially trucks), and the light intensity, wind direction, and wind speed have a significant effect on the emission diffusion of pollutants.