UNC studies, global coalition agree: decreasing short-term greenhouse gases benefits climate, health
|April 12, 2012|
Recent studies by UNC environmental scientists provide support to undergird a new international effort to reduce emissions of certain climate pollutants.
The effort, called the Climate and Clean Air Coalition to Reduce Short-Lived Climate Pollutants, was announced Feb. 16 by Secretary of State Hillary Rodham Clinton and includes the U.S. and five other countries. It targets emissions of black carbon (soot), methane, and hydrofluorocarbons, short-lived pollutants that influence climate.
J. Jason West, PhD, assistant professor of environmental sciences and engineering at UNC Gillings School of Global Public Health, has shown through several studies that these actions also will reduce air pollution and provide significant benefits to public health. His 2006 study was the first to quantify the health benefits of reducing methane emissions [PDF].
In research that appeared online ahead of print on March 7 in the journal Climatic Change, West and colleagues showed that aggressive actions to reduce methane emissions would reduce ozone air pollution globally. As a result, roughly 400,000 premature ozone-related deaths might be avoided by 2030. Methane is emitted by landfills, coal mines, oil and natural gas operations, and agricultural sources.
“There are cost-effective ways to reduce methane sources,” West says, “and when we monetized health benefits, we found that they outweigh the cost of emission reduction.”
West and Susan Anenberg, PhD, alumna of the UNC public health school and now an environmental specialist at the U.S. Environmental Protection Agency, co-authored a 2011 study about black carbon emissions [PDF]. Annenberg used methods developed in West’s lab to lead the U.N. Environment Program’s health impact analysis for an assessment of short-lived climate pollutants. That study, also co-authored with West and published online ahead of print on March 14 in Environmental Health Perspectives, analyzed 12 actions that reduce methane and soot. Using the year 2030 as a snapshot, they found that millions of lives might be saved that year by instating these measures.
“Many of the actions that reduce soot focus on inefficient industries and indoor wood burning for cooking in densely populated developing countries,” says Anenberg. “The health benefits of these actions are substantial because they reduce exposure to harmful pollutants in densely populated, developing countries.”
While long-lived greenhouse gases, such as carbon dioxide, have lifetimes of a century or more, soot is viable for about one week and methane for a decade. Still, these and other short-lived climate pollutants are responsible for more than one-third of current global warming.
“The Climate and Clean Air Coalition is strongly justified by its benefits for slowing climate change and improving public health over the next decades,” West says. “It’s satisfying to see the contributions from our research translated into action.”