WRF-Chem simulations of ozone pollution and control strategy in petrochemical industrialized and heavily polluted Lanzhou City, Northwestern China

Jixiang Li; Zhanxiang Wang; Lulu Chen; Lulu Lian; Yang Li; Liuyuan Zhao; Sheng Zhou; Xiaoxuan Mao; Tao Huang; Hong Gao; Jianmin Ma

doi:10.1016/j.scitotenv.2020.139835

WRF-Chem simulations of ozone pollution and control strategy in petrochemical industrialized and heavily polluted Lanzhou City, Northwestern China

Sci Total Environ. 2020 Oct 1:737:139835. doi: 10.1016/j.scitotenv.2020.139835. Epub 2020 May 30.

Authors

Jixiang Li¹, Zhanxiang Wang¹, Lulu Chen¹, Lulu Lian¹, Yang Li¹, Liuyuan Zhao¹, Sheng Zhou¹, Xiaoxuan Mao¹, Tao Huang¹, Hong Gao¹, Jianmin Ma²

Affiliations

¹ Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, PR China.
² Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, PR China; Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, PR China. Electronic address: jmma@pku.edu.cn.

PMID: 32526584
DOI: 10.1016/j.scitotenv.2020.139835

Abstract

As the largest petrochemical industrialized city in northwestern China since the 1950s, Lanzhou has been well-known for its heavy surface ozone pollution. Given abundant emission sources of ozone precursors and the favorable environmental conditions for O₃ formation, this study performed extensive atmospheric chemistry modeling investigations subject to 11 emission control scenarios. These scenarios increased and decreased emission levels of total volatile organic compound (TVOC) and nitrogen oxides (NO_x), the two surface ozone (O₃) precursor gases, to examine the relationships between O₃ and NO_x and TVOC. The modeling investigation was carried out for the summer of 2016 in the downtown and petrochemical industrial suburb in the city of Lanzhou. The results revealed that surface O₃ in the downtown area of Lanzhou was controlled by VOCs and in the petrochemical-industrialized western suburb by NO_x. Higher ozone levels were simulated in the west suburb of the city as compared with the downtown area, agreeing with measured data. The relationships between modeled TVOC/NO_x ratios and O₃ reductions, as well as the titration effect, were also discussed. The model results provided useful references for the mitigation strategy of ozone reduction in Lanzhou and other major cities in northwest China with similar climate and topography conditions.

Keywords: Emission scenario; Mitigation; O(3) formation; Precursor chemicals.