Air pollution in China: what is the cause and how to control it?

With rapid industrial and urban developments in China, air pollution has become an increasing concern of the public and governments.  The current major air-quality issues are severe haze caused by small particles (PM2.5), especially in winter, and photochemical ozone pollution in warm seasons. The air pollution is formed not only by emissions from pollution sources, but also is affected by meteorology and complex chemical reactions. Therefore, predicting and mitigating air pollution will need to understand the complex interplay among these factors. In this talk, I will first introduce some air pollution basics, describe air quality problems in Hong Kong and other parts of China, and then discuss the control measures in the past and the way forward. I will also show how research at PolyU has helped to understand the cause of air pollution and to support the development of the control policies.