Aggravating O 3 pollution due to NO x emission control in eastern China

Nan Wang, Xiaopu Lyu, Xuejiao Deng, Xin Huang, Fei Jiang, Aijun Ding

Research output: Journal article publicationJournal articleAcademic researchpeer-review

60 Citations (Scopus)

Abstract

During the past five years, China has witnessed a rapid drop of nitrogen oxides (NO x )owing to the wildly-applied rigorous emission control strategies across the country. However, ozone (O 3 )pollution was found to steadily deteriorate in most part of eastern China, especially in developed regions such as Jing-Jin-Ji (JJJ), Yangtze River Delta region (YRD)and Pearl River Delta region (PRD). To shed more light on current O 3 pollution and its responses to precursor emissions, we integrate satellite retrievals, ground-based measurements together with regional numerical simulation in this study. It is indicated by multiple sets of observational data that NO x in eastern China has declined more than 25% from 2012 to 2016. Based on chemical transport modeling, we find that O 3 formation in eastern China has changed from volatile organic compounds (VOCs)sensitive regime to the mixed sensitive regime due to NO x reductions, substantially contributing to the recent increasing trend in urban O 3 . In addition, such transitions tend to bring about an ~1–1.5 h earlier peak of net O 3 formation rate. We further studied the O 3 precursors relationships by conducting tens of sensitivity simulations to explore potential ways for effective O 3 mitigation. It is suggested that the past control measures that only focused on NO x may not work or even aggravate O 3 pollution in the city clusters. In practice, O 3 pollution in the three regions is expected to be effectively mitigated only when the reduction ratio of VOCs/NO x is greater than 2:1, indicating VOCs-targeted control is a more practical and feasible way.

Original languageEnglish
Pages (from-to)732-744
Number of pages13
JournalScience of the Total Environment
Volume677
DOIs
Publication statusPublished - 10 Aug 2019

Keywords

  • Emission sensitivity
  • Ozone pollution
  • Policy application
  • WRF-CMAQ

ASJC Scopus subject areas

  • Environmental Engineering
  • Environmental Chemistry
  • Waste Management and Disposal
  • Pollution

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