A new Stanford-led study offers compelling evidence that prescribed burns controlled low-intensity fires can significantly reduce the destructive impact of wildfires and limit hazardous smoke pollution across the western United States. The research, published June 26 in AGU Advances, found that such treatments lower wildfire intensity by an average of 16% and cut dangerous smoke emissions by 14%.
Using satellite data, land records, and smoke inventories, the study compared areas that underwent prescribed burns between late 2018 and spring 2020 with nearby untreated areas, all of which burned during the extreme 2020 wildfire season. The findings revealed a clear advantage for treated areas, which burned less severely and emitted substantially less smoke.
The study also highlighted a crucial public health benefit: prescribed burns release only 17% of the harmful fine particulate matter (PM2.5) that a wildfire would generate in the same location. PM2.5 from wildfires is increasingly recognized as a serious health threat linked to respiratory and heart problems. If California meets its target of treating one million acres annually, the state could cut over 650,000 tons of PM2.5 emissions within five years more than half the total from the catastrophic 2020 fire season.
However, not all regions benefit equally. In wildland-urban interface zones areas where development meets forest or shrubland prescribed burns were less effective, reducing fire severity by only 8.5%, compared to 20% in more remote areas. Safety concerns and dense populations often limit the use of fire in these zones, where mechanical thinning is the more common treatment.
The research team, including Stanford climate scientist Noah Diffenbaugh and environmental economist Marshall Burke, stressed that while prescribed fire isn’t a universal solution, it is one of the few proven tools for mitigating both wildfire risk and smoke exposure. They emphasized the need for more tailored fire strategies, especially as population growth accelerates in fire-prone areas.
With nearly $2 billion in federal funding earmarked for such wildfire mitigation treatments, the study’s authors hope the data will inform smarter, evidence-based policies to protect both landscapes and lives.
Refer: https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2025AV001682