Rising temperatures are expected to reduce the number of days conducive to prescribed fires by 17% on average across the western U.S., mostly during spring and summer, according to a recent study.
Prescribed fires are initiated by skilled firefighters to eliminate excess plant material.
This process helps curb conditions that could escalate a benign vegetation fire into a devastating blaze.
A shrinking timeframe for such burns indicates increasing difficulties for land managers in utilizing one of their primary strategies against major wildfires in the western United States.
In contrast, winter is forecasted to experience a 4% growth in the number of days suitable for controlled burns.
The majority of this increase is anticipated in the northern segment of the research area, potentially offering a silver lining for the Pacific Northwest.
In this region, winter prescribed burn periods are predicted to extend by 5 to 10 additional days.
Co-author Deepti Singh from Washington State University’s School of the Environment commented: “For the Pacific Northwest, the results are actually more optimistic.
“We already identify a pattern in this region towards a growing number of days conducive to prescribed fires in the winter and spring.
“We can leverage this trend for improved fire management.”
However, with ongoing drying and warming trends, summer windows for prescribed burns will decrease throughout much of the West.
This will perpetuate the risk of severe wildfires in both the Pacific Northwest and the drier southern regions of the western U.S.
Regional disparities were evident in the study.
In California, the escalating warm and dry conditions in coastal and southern zones imply that several areas could forfeit up to a month of days apt for prescribed burns annually.
Daniel Swain of UCLA, the study’s lead author, emphasized the need for the agencies in charge of controlled burns to adapt.
He noted that most personnel managing these fires are seasonal, with contracts ending by mid-autumn.
The evolving climate conditions necessitate changes in staffing patterns.
Swain stated: “Winter might emerge as a more favorable period for controlled burns, contingent upon the right policy and staffing shifts.”
By 2060, scientists anticipate a temperature rise of 2.0 degrees Celsius (3.6 degrees Fahrenheit). Swain labeled this forecast as “optimistic”, given the evident trajectory of even more pronounced warming.
“Despite present conditions, increased efforts are essential to counteract destructive fires,” he highlighted. “Current prescribed fire activities are insufficient to genuinely address the mounting wildfire challenge.”
The research, disseminated in Communications Earth and Environment, a Nature journal, saw contributions from UCLA, UC Berkeley, UC Merced, WSU, and the Nature Conservancy.
It delved into both past and projected climate scenarios and vegetation dryness, juxtaposing data from 1980–2020 with projections for 2020–2060.
Prescribed fires are becoming indispensable as wildfires in the American West intensify due to various factors, such as climate change, urban expansion in fire-sensitive areas, and past aggressive fire suppression strategies.
Recognizing future potentials and restrictions of this tool allows agencies to strategize, especially concerning the firefighting workforce.
Kristen Shive from UC Berkeley added: “This paper serves as a precursor. The hope is to adapt policies to either prolong contracts or establish winter-focused teams.”
The narrowing window for controlled burns, especially during critical spring and summer months, poses a significant challenge for fire and safety management in the western U.S.
Adapting to these changes necessitates innovative approaches, such as capitalizing on the potential increase in winter burn opportunities.
As the threat of wildfires continues to rise, proactive planning based on solid research, like this one, will be crucial in safeguarding communities and ecosystems.
