Concluding remarks: Faraday Discussion on air quality in megacities

Area of Science:

• Environmental Science
• Atmospheric Chemistry
• Public Health

Background:

• Megacities, with over 10 million people, confront significant environmental challenges, primarily air pollution.
• Economic and human activities in these urban areas generate emissions, leading to harmful atmospheric pollutants.
• Historical events like the London and Los Angeles smogs highlight the long-standing issue of air pollution.

Purpose of the Study:

• To provide an overview of megacity air pollution, covering emission sources, atmospheric processes, and impacts.
• To highlight knowledge gaps in understanding complex atmospheric transport, reaction mechanisms, and secondary particle formation.
• To discuss the influence of emerging emission sources and climate change on urban air quality and health.

Main Methods:

• Review of existing scientific understanding and literature on megacity air pollution.
• Analysis of atmospheric physicochemical processes and air quality trends.
• Examination of health and climate impacts associated with air pollution.

Main Results:

• Megacity air pollution poses risks to human health, regional environments, and contributes to climate change.
• Despite progress, complex atmospheric processes, secondary organic particle formation, and climate interactions remain poorly understood.
• Emerging emission sources and climate change introduce new challenges to managing air quality.

Conclusions:

• Continued research is crucial to address the multifaceted challenges of air pollution in megacities.
• Developing effective emissions reduction technologies and control measures requires a deeper understanding of atmospheric dynamics.
• Integrated strategies are needed to mitigate the adverse health and environmental impacts of megacity air pollution.