Analysis of traffic-related air pollution using Shanghai road traffic state index

摘要

Recently, due to the rapid economic development and the acceleration of urbanization, haze events have occurred frequently in most parts of China, which has attracted widespread attention at home and abroad. This study presents a statistical summary of air pollution concentrations and traffic state indexes from August 2014 to April 2015 in Shanghai, China. We find PM_(2.5)concentrations show a remarkable seasonal variability with ``winter > spring > autumn > summer'' in Shanghai. Concentrations of PM_(2.5), CO, NO_(2), SO_(2)are generally higher in winter than in summer due to enhanced anthropogenic and biogenic emissions and unsuitable meteorological conditions for pollution diffusion, contrary to concentrations of O_(3). The weekly changes of NO_(2)are highly consistent with that of traffic state indexes, suggesting a significant contribution to NO_(2)concentrations from road traffic emissions. Two moderate peaks are found in the diurnal variability of concentrations of PM_(2.5), CO and NO_(2), similar to road traffic indexes, indicating the important contribution of road traffic emissions every day. We find that SO_(2), NO_(2), CO are the dominant factors contributing to PM_(2.5)pollution, where NO_(2)and CO are mainly from road traffic emissions. The average annual Spearman correlation coefficient is r = 0.689 (p < 0.01), r = 0.564 (p < 0.01), r = 0.812 (p < 0.01), respectively.