Tropospheric ozone affects human health, crop yields, exacerbates global warming, and plays a crucial role in atmospheric chemistry processes. Previous studies have shown an increasing trend in tropospheric ozone under the influence of factors such as anthropogenic emissions and climate change, causing over 300,000 premature deaths globally each year. Particularly, surface ozone has attracted widespread attention due to its complex chemical processes and difficulty in control. International research programs like the Tropospheric Ozone Assessment Report (TOAR) systematically demonstrated the global distribution, trends, and driving factors of surface ozone before 2014. However, there is still a lack of systematic understanding of new challenges in ozone pollution control under the influence of climate change and anthropogenic emissions over the past decade.
Recently, the Cell sister journal One Earth published a Perspective article titled "A synergistic ozone-climate control to address emerging ozone pollution challenges". In response to the long-term environmental threat of ozone pollution, this article proposes a climate-coordinated ozone pollution control by revealing new challenges in global ozone pollution over the past decade, summarizing historical governance experiences in different countries.
This study utilizes surface ozone observation data from over 4,300 monitoring sites worldwide, over the past decade to depict the spatial distribution of current global warm-season ozone pollution. It identifies key regions where ozone has rapidly increased from 2014 to 2019, with significant increases observed at 49% of monitoring sites in China, 25% in the United States, and 6.4% in Europe. This mainly reflects two major challenges faced by global ozone pollution: the difficulty of ozone pollution control in regions with rapidly changing emissions and the dominant role of climate warming (heatwaves, wildfires, etc.) in the ozone rebound in regions with emission reductions. The study further confirms this conclusion through a literature review and global atmospheric chemistry model simulations.
Summarizing the lessons learned from decades of air pollution control experiences in China, the United States, Europe, and other countries, it is found that past successful strategies such as precursor synergistic control and regional coordinated control in Europe and the United States are no longer effective in addressing ozone pollution under rapid climate warming over the past decade, and they are not entirely applicable to the synergistic control of ozone and particulate matter in high-pollution environments. Given the complex coupling relationship between ozone pollution and climate change, this article proposes and elaborates on an ozone-climate synergistic control strategy based on the health of humans and ecosystems, with emission-mechanism-policy as the chain, including the joint control of multiple pollutants. This strategy, based on comprehensive environmental health indicators, is conducive to promoting international cooperation in ozone pollution control.
This achievement was jointly completed by Professor Ke Li from our School of Environmental Science and Engineering (co-first author) and many researchers from 25 research institutions in 10 countries worldwide, including Assistant Professor Xiaopu Lyu from Hong Kong Baptist University (co-first author), Professor Hai Guo from The Hong Kong Polytechnic University (corresponding author), and Professor Lidia Morawska from Queensland University of Technology (corresponding author).
