Correlation between surface PM2,5 and ozone during 2014-2019 in Beijing and Nanjing

• Published in: Nanjing Xinxi Gongcheng Daxue Xuebao Vol. 12; no. 6; pp. 656 - 664
• Main Authors: Jinjin, Sun, Lin, Huang, Kangjia, Gong, Xueying, Wang, Jingyi, Li, Momei, Qin, Xingna, Yu, Jianlin, Hu
• Format: Journal Article
• Language: Chinese
• Published: Nanjing Nanjing University of Information Science & Technology 01.12.2020
• Subjects: Autumn; Correlation coefficient; Correlation coefficients; Diurnal variations; Ozone; Particulate matter; Spring (season); Summer; Time; Beijing China; China
• ISSN: 1674-7070
• DOI: 10.13878/j.cnki.jnuist.2020.06.002

It is particularly important to clarify the correlation between fine particulate matter ( PM2_5 ) and O3(P-O) in account of the seemingly increasing surface ozone and decreasing PM2 5 trends in China since 2014. Therefore ,ohservations of hourly PM2 5 and O3 data for Beijing and Nanjing during 2014 to 2019 were summarized to reveal their P-O correlations.The observations showed a decreasing trend of annual average PM2 5 mass concentration,which was -6. 86 and -6. 15 p.g·m 3 ·a 1 for Beijing and Nanjing, respectively. While the annual maximum daily 8-hour average O3(MDA8 O3) increased by 1. 50 and 1. 75 p.g·m 3·a 1 for Beijing and Nanjing,respectively. O3 pollution became more serious in summer for both cities.For Beijing,when O3 mass concentration was below/above 100 p.g·m 3,the increase of O3 concentration would correspond to the decrease/increase of PM2 5 concentration,indicating a negative/positive P-O correlation.The same varying P-O correlation existed for Nanjing ,except for the different critical value