Spatiotemporal Distribution of PM_2.5 and O₃ and Their Interaction During the Summer and Winter Seasons in Beijing, China

• Main Authors: Hui Zhao, Youfei Zheng, Chen Li
• Format: Article
• Language: English
• Published: MDPI AG 2018-11-01
• Series: Sustainability
• Subjects: atmospheric pollution; particulate matter; PM_2.5; Ozone
• Online Access: https://www.mdpi.com/2071-1050/10/12/4519

This study analyzed the spatiotemporal variations in PM_2.5 and O₃, and explored their interaction in the summer and winter seasons in Beijing. To this aim, hourly PM_2.5 and O₃ data for 35 air quality monitoring sites were analyzed during the summer and winter of 2016. Results suggested that the highest PM_2.5 concentration and the lowest O₃ concentration were observed at traffic monitoring sites during the two seasons. A statistically significant (<i>p</i> &lt; 0.05) different diurnal variation of PM_2.5 was observed between the summer and winter seasons, with higher concentrations during daytime summer and nighttime winter. Diurnal variations of O₃ concentrations during the two seasons showed a single peak, occurring at 16:00 and 15:00 in summer and winter, respectively. PM_2.5 presented a spatial pattern with higher concentrations in southern Beijing than in northern areas, particularly evident during wintertime. On the contrary, O₃ concentrations presented a decreasing spatial trend from the north to the south, particularly evident during summer. In addition, we found that PM_2.5 concentrations were positively correlated (<i>p</i> &lt; 0.01, <i>r</i> = 0.57) with O₃ concentrations in summer, but negatively correlated (<i>p</i> &lt; 0.01, <i>r</i> = &#8722;0.72) with O₃ concentrations in winter.