Carbon monoxide emissions from industrial production have serious consequences for human health and are a strong indicator of overall air pollution levels. Many countries aim to reduce their emissions, but they cannot control air flows originating in other regions. A new study from the University of Illinois Urbana-Champaign looks at global flows of air pollution and how they relate to economic activity in the global supply chain.
“Our study is unique in combining atmospheric transport of air pollution with supply chain analysis as it tells us where the pollution is coming from and who is ultimately responsible for it,” said lead author Sandy Dall’erba, professor in the Department of Agricultural and Consumer Economics (ACE) and director of the Center for Climate, Regional, Environmental and Trade Economics (CREATE), both part of the College of Agricultural, Consumer and Environmental Sciences (ACES) at Illinois. 
“There is a direct link between a country’s level of production and how much air pollution is emitted. But production may be driven by demand from consumers in other countries. We use supply chain analysis to quantify the links between production and consumption. This helps us to understand how production in one country is linked to domestic and foreign demand,” he added. 
The researchers traced the movement of pollutants through the atmosphere to understand the flow of emissions, using simulations developed by Nicole RIemer, professor in the Department of Climate, Meteorology & Atmospheric Sciences, College of Liberal Arts & Sciences at Illinois. For analytical purposes, they divided the world into five sections: the United States, Europe, China, South Korea, and the rest of the world. South Korea is located downwind of China, and it serves as an example of how a small country can be affected by pollution from a much larger upwind neighbor.
“Over recent years, South Korea has taken several measures to reduce its own pollution, yet it has experienced worsening air quality. Why? The answer is to be found in its upwind neighbor, China. Yet, a large amount of the goods manufactured in China are destined for foreign consumers in the U.S. and in Europe, among other places. As such, who is to be blamed for the increase in air pollution in South Korea? That is the challenge we embarked on with this study,” Dall’erba stated.
The researchers found the amount of carbon monoxide emissions coming from China to South Korea increased from 30 teragrams (Tg) in 1990 to 42 Tg in 2014.
“To put these numbers in perspective, 5 Tg of carbon monoxide corresponds to the emissions from all of the cars in the U.S. – roughly 274 million – each driving 13,500 miles per year. So it’s definitely not a small increase. We conclude that South Korea has, in effect, lost control of their own air quality,” Dall’erba explained.
This content is taken from University of Illinois College of Agricultural, Consumer and Environmental Sciences

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