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Atmos. Chem. Phys. Discuss., 12, 9161-9194, 2012
www.atmos-chem-phys-discuss.net/12/9161/2012/ doi:10.5194/acpd-12-9161-2012 © Author(s) 2012. This work is distributed under the Creative Commons Attribution 3.0 License. |
Ozone production in the megacities of Tianjin and Shanghai, China: a comparative study
1Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing, China
2Tianjin Academy of Environmental Sciences, Tianjin, China
3Tianjin Institute of Meteorological Science, Tianjin, China
4Chinese Academy of Meteorological Sciences, China Meteorological Administration, Beijing, China
5Shanghai Meteorological Administration, Shanghai, China
*now at: Meteorological Observation Center, China Meteorological Administration, Beijing, China
**now at: Key Laboratory of Middle Atmosphere and Global Environment Observation, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
Abstract. Rapid economic growth has given rise to a significant increase in ozone precursor emissions in many regions of China, especially in the densely populated North China Plain (NCP) and Yangtze River Delta (YRD). Improved understanding of ozone formation in response to different precursor emissions is imperative to address the highly nonlinear ozone problem and to provide a solid scientific basis for efficient ozone abatement in these regions. A comparative study on ozone photochemical production in summer has thus been carried out in the megacities of Tianjin (NCP) and Shanghai (YRD). Two intensive field campaigns were carried out respectively at an urban and a suburban site of Tianjin, in addition to routine monitoring of trace gases in Shanghai, providing data sets of surface ozone and its precursors including nitrogen oxides (NOx) and various volatile organic compounds (VOCs). Ozone pollution was found to be more severe in Tianjin than in Shanghai during the summer, either based on the frequency or the duration of high ozone events. Such differences might be attributed to the large amount of highly reactive VOC mixture in the Tianjin region. It is found that industry related species like light alkenes were of particular importance in both urban and suburban Tianjin, while in Shanghai aromatics dominate. In general, the ozone problem in Shanghai is on an urban scale. Stringent control policies on local emissions would help reduce the occurrence of high ozone concentrations. By contrast, ozone pollution in Tianjin is a regional problem. Combined efforts to reduce ozone precursor emissions on a regional scale must be undertaken to bring the ozone problem under control.
Citation: Ran, L., Zhao, C. S., Xu, W. Y., Han, M., Lu, X. Q., Han, S. Q., Lin, W. L., Xu, X. B., Gao, W., Yu, Q., Geng, F. H., Ma, N., Deng, Z. Z., and Chen, J.: Ozone production in the megacities of Tianjin and Shanghai, China: a comparative study, Atmos. Chem. Phys. Discuss., 12, 9161-9194, doi:10.5194/acpd-12-9161-2012, 2012.