New data shows targeted fire management reduces wildfire severity by 16% and smoke pollution by 14% with major implications for public health and climate resilience.
As wildfire seasons grow longer and deadlier across the American West new Stanford-led study offers compelling evidence that prescribed burns controlled, low-intensity fires can significantly reduce wildfire destruction and the harmful smoke that blankets large swaths of the country.
Published on June 26 in AGU Advances, the study found that prescribed fires reduced wildfire intensity by an average of 16% and slashed smoke pollution by 14%, offering a rare empirical look at the effectiveness of this widely promoted but still underutilized fire management strategy.
“Prescribed fire is often promoted in theory, but we show it clearly works in practice,” said lead author Makoto Kelp, a postdoctoral fellow in Earth system science at the Stanford Doerr School of Sustainability. “It’s not a silver bullet, but it’s one of the best tools we have to reduce harm from extreme wildfires.”
Data-Driven Evidence from a Record Fire Season
The research, conducted in collaboration with Stanford climate scientist Noah Diffenbaugh and environmental economist Marshall Burke, used high-resolution satellite imagery, land management records, and smoke emissions data to compare areas that received prescribed burns between late 2018 and spring 2020 with adjacent untreated regions. Both areas were later scorched by the unprecedented 2020 fire season.
The team found that treated areas not only burned less severely but also released far less PM2.5 the fine particulate matter that is linked to respiratory and cardiovascular illnesses. “People often think of wildfires as flames and evacuations,” said Burke. “But smoke is a silent, far-reaching hazard, and prescribed fire may be one of the few tools that actually reduces total smoke exposure.”
Not All Treatments Are Created Equal
The study also found a striking difference in the effectiveness of prescribed burns based on geography. In non-urban wildland areas, fire severity dropped by 20% following prescribed burns. In contrast, in wildland-urban interface (WUI) zones where homes meet wild vegetation the reduction was only 8.5%, likely due to safety concerns limiting burn size and intensity.
Diffenbaugh emphasized the urgency of improving fire strategies in WUI regions. “These are the fastest-growing areas in terms of population, and they’re also the most climate-sensitive when it comes to wildfire risk,” he said. “We need to understand why prescribed fire treatments are less effective there and what alternatives or improvements are possible.”
Health Gains Outweigh Smoke Concerns
While public skepticism around prescribed fires often centers on the smoke they produce, the study found that these controlled burns emit just 17% of the PM2.5 that would be released if the same area burned in a wildfire. If California were to meet its goal of one million acres of prescribed burns annually, the researchers estimate a potential cut of 655,000 tons of PM2.5 over five years more than half of the smoke emissions from the catastrophic 2020 fire season alone.
Kelp pointed out that these estimates are likely conservative. “Prescribed burns also have protective benefits that extend into surrounding areas, creating firebreaks that can stop or slow wildfires from spreading.”
Policy Momentum and the Path Forward
Despite these benefits, prescribed burning has seen only modest expansion in recent years, even with nearly $2 billion in federal funding available for wildfire mitigation. Public concerns over smoke and the risk of fires escaping containment remain major barriers.
The Stanford study could help shift that conversation, offering hard data to support smarter fire management policies. “This kind of empirical evidence is critical for effective policy,” said Kelp. “It shows that when done correctly, prescribed fire not only works it saves lives, protects landscapes, and improves public health.”
The research was supported by the National Oceanic and Atmospheric Administration and Stanford University as part of the NOAA Climate and Global Change Postdoctoral Fellowship Program.
As climate change intensifies the wildfire threat, the study underscores that proactive, science-based strategies like prescribed fire must play a central role in safeguarding communities and ecosystems across the West.