| Summary: | This study analyzed the spatiotemporal variations in PM<sub>2.5</sub> and O<sub>3</sub>, and explored their interaction in the summer and winter seasons in Beijing. To this aim, hourly PM<sub>2.5</sub> and O<sub>3</sub> data for 35 air quality monitoring sites were analyzed during the summer and winter of 2016. Results suggested that the highest PM<sub>2.5</sub> concentration and the lowest O<sub>3</sub> concentration were observed at traffic monitoring sites during the two seasons. A statistically significant (<i>p</i> < 0.05) different diurnal variation of PM<sub>2.5</sub> was observed between the summer and winter seasons, with higher concentrations during daytime summer and nighttime winter. Diurnal variations of O<sub>3</sub> concentrations during the two seasons showed a single peak, occurring at 16:00 and 15:00 in summer and winter, respectively. PM<sub>2.5</sub> presented a spatial pattern with higher concentrations in southern Beijing than in northern areas, particularly evident during wintertime. On the contrary, O<sub>3</sub> concentrations presented a decreasing spatial trend from the north to the south, particularly evident during summer. In addition, we found that PM<sub>2.5</sub> concentrations were positively correlated (<i>p</i> < 0.01, <i>r</i> = 0.57) with O<sub>3</sub> concentrations in summer, but negatively correlated (<i>p</i> < 0.01, <i>r</i> = −0.72) with O<sub>3</sub> concentrations in winter.
|
|---|
