Temporal and spatial characteristics of PM2.5 concentration in urban street canyons and analysis on the affecting factors
ZHANG Yun-wei1, WANG Qing-ru1, CHEN Jia1, LIU Sui-xin2, HU Ta-feng2, GU Zhao-lin1
1. School of Human Settlements and Civil Engineering, Xi'an Jiaotong University, Xi'an 710049, China; 2. Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710077, China
Abstract：In the current work, temporal variations of PM2.5 concentration, traffic flux, wind speed, air temperature and humidity was measured on Heping Road, which well represents an urban the street canyon, during April 8~10, 2015, in Xi'an. Based on these measurements, diurnal and spatial variations of PM2.5 in the urban street canyon and the affecting factors were investigated. Generally, PM2.5 concentrations were found very high in the street canyon, especially in the morning and evening. The lowest PM2.5 concentrations were observed at 16:00 in the daytime. Good correlations were found between PM2.5 concentration and air temperature and/or humidity, with R2 values of 0.75 and 0.81, respectively. Under weak wind conditions, the temperature variation induced expansion and contraction was found to be the main influencing factor on pollutant dispersion in urban street canyons.
张云伟, 王晴茹, 陈嘉, 刘随心, 胡塔峰, 顾兆林. 城市街谷内PM2.5浓度时空变化及影响因素分析[J]. 中国环境科学, 2016, 36(10): 2944-2949.
ZHANG Yun-wei, WANG Qing-ru, CHEN Jia, LIU Sui-xin, HU Ta-feng, GU Zhao-lin. Temporal and spatial characteristics of PM2.5 concentration in urban street canyons and analysis on the affecting factors. CHINA ENVIRONMENTAL SCIENCECE, 2016, 36(10): 2944-2949.
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