The temporal and spatial variations of air pollutant concentrations, and types of pollution were investigated during heavy air pollution episodes occurred in Beijing from 2013 to 2014. The results showed that there were 105heavy pollution days in Beijing during 2013~2014, accounting for 14.4% of the total. And in these heavy air pollution episodes, Beijing suffered the PM2.5, PM10 and O3 as the primary pollutant for 103 days, 1day and 1day, respectively. The heavy pollution days in the winter half year accounted for 76.2%, and pollution episodes could be characterized by calm wind, high relative humidity and low visibility. For the heavy air pollution days, the concentration ratio of PM2.5 to PM10 reached to 91.3% which was significantly higher than the annual average level, indicating that PM2.5 was dominant. Air pollutant concentrations in the southern region of Beijing were higher than those in the northern parts. Areas with higher air pollutant concentrations were mainly located in the plains, and lower values are located in the mountain regions. Moreover, the frequency of heavy air pollution for traffic monitoring sites was higher than other urban sites in Beijing. The heavy air pollution episodes could be grouped into four typical types, namely the sustained-accumulated, the O3 pollution, the sand-dust caused and the combined type. The sustained-accumulated episodes were always accompanied by enhancements of regional air pollution level for the whole city, and by obvious increase of NO3-, SO42- and NH4+ concentrations in PM2.5. It is also found that O3 pollution became more serious in recent years.
李令军, 王占山, 张大伟, 陈添, 姜磊, 李云婷. 2013~2014年北京大气重污染特征研究[J]. 中国环境科学, 2016, 36(1): 27-35.
LI Ling-jun, WANG Zhan-shan, ZHANG Da-wei, CHEN Tian, JIANG Lei, LI Yun-ting. Analysis of heavy air pollution episodes in Beijing during 2013~2014. CHINA ENVIRONMENTAL SCIENCECE, 2016, 36(1): 27-35.
Li W J, Zhang D Z, Shao L Y, et al. Individual particle analysis of aerosols collected under haze and non-haze conditions at a high-elevation mountain site in the North China plain[J]. Atmospheric Chemistry and Physics, 2011,11(22):11733-11744.
[2]
Chen L W A, Chow J C, Doddridge B G, et al. Analysis of a summertime PM2.5 and haze episode in the mid-Atlantic region[J]. Journal of the Air & Waste Management Association, 2003, 53(8):946-956.
Zhang W, Capps S L, Hu Y, et al. Development of the high-order decoupled direct method in three dimensions for particulate matter:enabling advanced sensitivity analysis in air quality models[J]. Geoscientific Model Development, 2012,5(2):355-368.
An X, Zhu T, Wang Z, et al. A modeling analysis of a heavy air pollution episode occurred in Beijing[J]. Atmospheric Chemistry and Physics, 2007,7(12):3103-3114.
Pan X L, Yan P, Tang J, et al. Observational study of influence of aerosol hygroscopic growth on scattering coefficient over rural area near Beijing mega-city[J]. Atmos. Chem. Phys., 2009,9:7519-7530.
Wang T, Nie W, Gao J, et al. Air quality during the 2008 Beijing Olympics:secondary pollutants and regional impact[J]. Atmospheric Chemistry and Physics, 2010,10(16):7603-7615.
[22]
Wang Y S, Yao L, Wang L L, et al. 2014. Mechanism for the formation of the January 2013 heavy haze pollution episode over central and eastern China[J]. Science China:Earth Sciences, 57:14-25.
[23]
Lu K D, Rohrer F, Holland F, et al. Observation and modelling of OH and HO2 concentrations in the Pearl River Delta 2006:a missing OH source in a VOC rich atmosphere[J]. Atmospheric Chemistry and Physics, 2012,12(3):1541-1569.