Climate Change Could Worsen Air Quality Impacts of Prescribed Burns

Prescribed burning, which is a frequent land management method throughout the lower southeast United States, is important for avoiding megafires, maintaining ecological health, and lowering underbrush. But a new North Carolina State University study indicates that although such fires are still needed, they are also a significant source of air pollution—particularly in areas where low-income and minority populations reside.

A study released in Environmental Research Letters says prescribed fires now contribute 5% to 10% to annual fine particulate matter (PM2.5) pollution in the Southeast. Where prescribed burning is most concentrated—most notably in the tri-state area where Alabama, Florida, and Georgia share borders—PM2.5 contributions are down 15% to 25%.

The study, drawing on 2018 data, applied federal air quality and emissions records, projected climate, and 223 land manager surveys in the Southeast. The findings indicate a troubling trend: climate change will likely make it harder to schedule prescribed burns, yet heighten their health and environmental impacts.

Land managers are already subject to limitations, as excessive heat, drought, and strong winds limit the number of available safe burn days. According to the study, fewer viable days will lead to more burns being conducted at a time when they are done or across more land area, making emissions more concentrated and increasing the magnitude of air pollution within shorter times.

Additionally, these following consecutive days that are feasible are projected to shift towards winter and spring seasons. Meteorological conditions during the months may increase the fire plume's effect of pollution, which will augment exposure of communities in the neighborhood to PM2.5.

These smoke-affected prescribed burn communities consist of lower-income individuals and higher percentages of people of colour, as witnessed especially in the high-burn counties in the Southeast. Although present PM2.5 concentrations in these locations are not above national air quality standards, the research indicates that future climate change will necessitate these communities going into non-attainment.

The modelling for the study presumed that the future land area to be managed through prescribed burning would be at 2018 levels. Policy changes towards increasing prescribed burning under wildfire risk can lead to PM2.5 emissions, further contaminating the air unless measures are put in place to counteract.

Land manager survey data show that the majority already consider smoke management to be a restriction on their ability to perform prescribed burns. Because climate change will likely decrease burn days and increase smoke levels, these issues are likely to become more severe.

Resolving the problems is a two-faceted effort: understanding the need for prescribed burning as a method of wildfire prevention and forest management, yet simultaneously trying to eliminate public health impacts. This can be done by better smoke modelling, better scheduling to stay out of severe atmospheric conditions, investment in air quality monitoring, and public education in high-risk communities.

The research suggests the need for reconciling environmental management policy with human health factors, particularly with climate trends still unfolding. The authors observe that prescribed burns are an important tool, but their growing air quality repercussions should be considered in future land use and public health policy decisions.

The results are presented in the paper Impacts of Climate Change on Land Management and Wildland Fire Smoke in the Southeastern United States by Megan M. Johnson et al., published in Environmental Research Letters in 2025. The study was conducted by North Carolina State University.