Revealing the modulation of boundary conditions and governing processes on ozone formation over northern China in June 2017

Feifan Yan; Yang Gao; Mingchen Ma; Cheng Liu; Xiangguang Ji; Fei Zhao; Xiaohong Yao; Huiwang Gao

doi:10.1016/j.envpol.2020.115999

Revealing the modulation of boundary conditions and governing processes on ozone formation over northern China in June 2017

Environ Pollut. 2021 Mar 1:272:115999. doi: 10.1016/j.envpol.2020.115999. Epub 2020 Nov 11.

Authors

Feifan Yan¹, Yang Gao², Mingchen Ma¹, Cheng Liu³, Xiangguang Ji⁴, Fei Zhao⁵, Xiaohong Yao⁶, Huiwang Gao⁶

Affiliations

¹ Key Laboratory of Marine Environment and Ecology, and Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ministry of Education, Ocean University of China, Qingdao, 266100, China.
² Key Laboratory of Marine Environment and Ecology, and Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ministry of Education, Ocean University of China, Qingdao, 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China. Electronic address: yanggao@ouc.edu.cn.
³ Key Lab of Environmental Optics and Technology, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, China; Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, 230026, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China.
⁴ School of Environmental Science and Optoelectronic Technology, University of Science and Technology of China, Hefei, 230026, China.
⁵ Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, 230026, China.
⁶ Key Laboratory of Marine Environment and Ecology, and Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ministry of Education, Ocean University of China, Qingdao, 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China.

PMID: 33218775
DOI: 10.1016/j.envpol.2020.115999

Abstract

In this study, ozonesonde data were used to evaluate the impact of different boundary conditions on the vertical distribution of ozone over urban Beijing. The comparison shows that the clean and static boundary conditions, referred to as PROFILE, apparently underestimate the ozone concentration over the upper troposphere and stratosphere, whereas the global chemical transport model (CTM) provides much more reasonable performance. Further investigation reveals that the boundary conditions exert larger impacts over areas with high altitudes and close distances to boundaries, such as the Tibetan Plateau, while they yield weak impacts on regions relatively far from the boundary, such as the North China Plain (NCP). Process analysis was conducted to investigate the modulation of physical and chemical processes on ozone formation in June 2017, illustrating that during the daytime of the high-O₃ period, the photochemical reactions within the planetary boundary layer (PBL) almost become the only source favorable to ozone accumulation. Motivated by this phenomenon, we constructed a linear regression and found that the maximum daily 8-hr ozone (MDA8) ozone concentration was highly correlated with the surface ozone change rate and chemical reactions in the PBL during the pollution period, with MDA8 ozone exceeding 70 ppbv over NCP. Based on this relationship as well as the design of numerical experiments, we propose a strategy of dynamic emission control. Firstly, the emission reduction during the peak ozone formation period may weaken the fast chemical reactions in the PBL and subsequent surface ozone concentration. Secondly, emission reduction one or two days prior to an episode might achieve larger ozone reduction through the accumulation effect. Lastly, emission control outside of the NCP may surpass the local impact under favorable meteorological conditions. Therefore, the efficacy of dynamic emission control was striking when both the accumulation and transport effect were taken into consideration.

Keywords: Boundary conditions; Dynamic emission control; Ozone; PBL; Process analysis.

MeSH terms

Air Pollutants* / analysis
Beijing
China
Environmental Monitoring
Ozone* / analysis

Substances

Air Pollutants
Ozone