How Prescribed Burns Could Limit Megafires in California, Oregon, and Washington

Typography

Wildfire smoke is a threat to air quality, public health, and ecosystems throughout the U.S. Notwithstanding the impact of this year’s Canadian wildfires, the West typically sees much higher exposure to wildfire smoke than other regions of the country.

Wildfire smoke is a threat to air quality, public health, and ecosystems throughout the U.S. Notwithstanding the impact of this year’s Canadian wildfires, the West typically sees much higher exposure to wildfire smoke than other regions of the country. New research from Harvard University, the U.S. Forest Service, and National Oceanic and Atmospheric Administration indicates that controlled burns – particularly in coastal areas of northern California and the Pacific Northwest – could dramatically reduce the overall amount of wildfire smoke exposure in vulnerable rural communities and dense population centers across the West. The findings are published online in Earth’s Future.

“Since the early 1900s, a legacy of fire suppression in the West in combination with a warming climate have contributed to severe wildfires. Until now, there hasn’t been much research into how land management methods might influence smoke exposure,” says Makoto Kelp, the paper’s lead author, who earned his Ph.D. from Harvard as a member of the Atmospheric Chemistry Modeling Group.

“Smoke consists of a mix of gases and tiny particles. The particles are bad to breathe because they can get deep into your lungs and trigger a slew of acute and chronic diseases,” says modeling group co-leader Loretta Mickley, senior author of the paper and a Senior Research Fellow at the Harvard John A. Paulson School of Engineering and Applied Sciences. “Drier and warmer conditions, together with accumulated underbrush, have made the West more vulnerable to large, severe wildfires. Implementing smaller, prescribed fires could make it more difficult for out-of-control wildfires to spread. These controlled fires still emit smoke, but the net benefit is less smoke pollution overall.”

Read more at: Harvard John A. Paulson School of Engineering and Applied Science

Where the 2020 fires contributed the most to smoke exposure over the western US. Red indicates the areas with the most smoke impact in September 2020, averaged over the western US and weighted for population. Blue indicates fires with the least smoke impact. (Photo Credit: Harvard SEAS)

Dooki (Combretum glutinosum) trees grow on a millet field in Niger. (Photo Credit: P. SAVADOGO / ICRAF)