Cutting carbon emissions more than pays for itself with savings on health care spending
“If cost-benefit analyses of climate policies don’t include the significant health benefits from healthier air, they dramatically underestimate the benefits of these policies,” says lead author Tammy Thompson, now at Colorado State University, who conducted the research as a postdoc in Selin’s group.
Most detailed assessment to date
The study is the most detailed assessment to date of the interwoven effects of climate policy on the economy, air pollution, and the cost of health problems related to air pollution. The MIT group paid especially close attention to how changes in emissions caused by policy translate into improvements in local and regional air quality, using comprehensive models of both the economy and the atmosphere.
In addition to carbon dioxide, burning fossil fuels releases a host of other chemicals into the atmosphere. Some of these substances interact to form ground-level ozone, as well as fine particulate matter. The researchers modeled where and when these chemical reactions occurred, and where the resulting pollutants ended up — in cities where many people would come into contact with them, or in less populated areas.
The release notes that the researchers projected the health effects of ground-level ozone and fine particulate matter, two of the biggest health offenders related to fossil-fuel emissions. Both pollutants can cause asthma attacks and heart and lung disease, and can lead to premature death.
In 2011, 231 counties in the U.S. exceeded the EPA’s regulatory standards for ozone, the main component of smog. Standards for fine particulate matter — airborne particles small enough to be inhaled deep into the lungs and even absorbed into the bloodstream — were exceeded in 118 counties.
While cutting carbon dioxide from current levels in the U.S. will result in savings from better air quality, pollution-related benefits decline as carbon policies become more stringent. Selin cautions that after a certain point, most of the health benefits have already been reaped, and additional emissions reductions won’t translate into greater improvements.
“While air-pollution benefits can help motivate carbon policies today, these carbon policies are just the first step,” Selin says. “To manage climate change, we’ll have to make carbon cuts that go beyond the initial reductions that lead to the largest air-pollution benefits.”
The study shows that climate policies can also have significant local benefits not related to their impact on climate, says Gregory Nemet, a professor of public affairs and environmental studies at the University of Wisconsin at Madison who was not involved in the study.
“A particularly notable aspect of this study is that even though several recent studies have shown large co-benefits, this study finds large co-benefits in the U.S., where air quality is assumed to be high relative to other countries,” Nemet says. “Now that states are on the hook to come up with plans to meet federal emissions targets by 2016, you can bet they will take a close look at these results.”
— Read more in Tammy M. Thompson et al., “A systems approach to evaluating the air quality co-benefits of US carbon policies,” Nature Climate Change (24 August 2014) (doi:10.1038/nclimate2342)
