Ground-level ozone pollution in China: a synthesis of recent findings on influencing factors and impacts

Abstract

Ozone (O _3 ) in the troposphere is an air pollutant and a greenhouse gas. In mainland China, after the Air Pollution Prevention and Action Plan was implemented in 2013—and despite substantial decreases in the concentrations of other air pollutants—ambient O _3 concentrations paradoxically increased in many urban areas. The worsening urban O _3 pollution has fuelled numerous studies in recent years, which have enriched knowledge about O _3 -related processes and their impacts. In this article, we synthesise the key findings of over 500 articles on O _3 over mainland China that were published in the past six years in English-language journals. We focus on recent changes in O _3 concentrations, their meteorological and chemical drivers, complex O _3 responses to the drastic decrease in human activities during coronavirus disease 2019 lockdowns, several emerging chemical processes, impacts on crops and trees, and the latest government interventions.

Keywords

• ozone
• O3
• China
• ozone trend
• ozone impact on crops and forests
• ozone formation and transport