Prescribed burns, used for land management and wildfire prevention, are significant contributors to air pollution in the southeastern United States. A recent study highlights that these effects could intensify as climate change progresses.
Fernando Garcia-Menendez, an associate professor at North Carolina State University, explains that “smoke from prescribed burns can also pose challenges to air quality,” with climate change potentially reducing the number of days suitable for such activities due to high temperatures, drought, or strong winds.
Megan Johnson, a Ph.D. graduate from NC State and first author of the paper, notes the importance of understanding how prescribed burns currently affect air quality in the Southeast and their potential future impact.
The research utilized 2018 federal data on air quality and emissions alongside climate change projections. A survey of 223 land managers provided insights into how weather conditions influence decisions about prescribed burns and their views on future impacts of climate change.
The study found that prescribed burns account for 5-10% of particulate matter (PM2.5) pollution annually across the Southeast but rise to 15-25% in areas with frequent burns near Alabama, Florida, and Georgia. These regions house around two million people who predominantly belong to minority and low-income groups.
“Right now, these regions are not violating air quality standards for PM2.5,” says Johnson. However, compliance may become challenging due to climate change.
Climate change could lead to more burns being conducted on viable days or larger areas being burned simultaneously. This would result in increased smoke emissions on those days.
Johnson points out that viable burn days might occur more often in spring and winter when pollution effects are heightened despite safe burning conditions being met.
Garcia-Menendez emphasizes that land managers already find smoke management a limiting factor for conducting prescribed burns due to air quality concerns—a challenge likely to worsen with time.
The study assumes that the area treated with prescribed burns will remain constant between 2055-2059 compared to 2018 levels. However, there is a push to increase such activities to reduce underbrush contributing to wildfires. If this occurs, it will further impact air quality.
Garcia-Menendez states: “That doesn’t mean those burns aren’t necessary, but it is something we would have to address in terms of both public health and public policy.”
The findings are published in Environmental Research Letters under “Impacts of Climate Change on Land Management and Wildland Fire Smoke in the Southeastern United States.” The research received support from the National Science Foundation and other institutions.
