Regional clean air efforts in China’s national capital region can boost air pollution in other parts of the country, according to a new study (Sci. Adv., 2019, DOI: 10.1126/sciadv.aav4707).
An international team of researchers led by Delin Fang of Beijing Normal University used computer models to examine the effects of policies to reduce particulate matter with diameter of 2.5 µm or less in the cities of Beijing and Tianjin and in Hebei Province. The three areas, considered collectively to be the national capital region, often suffer from extremely high levels of particulate matter pollution.
The researchers found that emission control policies in the region would shift polluting industries and power generation out of the area and into other parts of China, especially neighboring provinces. This, in turn, would raise particulate matter pollution levels in those provinces. And wind potentially could carry emissions from these areas to the national capital region, canceling out part or all of the region’s efforts to cut air pollution, the researchers say.
They also point out that many of the power plants and factories outside of the capital region are older and technologically inferior, especially when it comes to efficiency and emissions controls. So shifting activity to those facilities would likely lead to a net increase in total pollution and greenhouse gas emissions, the researchers say.