Climate Change Will Limit Ability to Control Wildland Fires, Scientists Say

Changes in climate will limit humans’ ability to manage wildland fire and apply prescribed fire across the landscape, according to the “San Diego Declaration on Climate Change and Fire Management,” a report by the Association for Fire Ecology, an assembly of fire ecologists.

“Under future drought and high heat scenarios,” the Declaration reads, “fires may become larger more quickly and be more difficult to manage. Fire suppression costs may continue to increase, with decreasing effectiveness under extreme fire weather and fuel conditions. Extreme fire events are likely to occur more frequently.”

Association President Robin Wills of Oakland, Calif. said the five-page Declaration is being submitted for delegate concurrence at the Third International Fire Ecology and Management Congress to be held Nov. 13-17, 2006, in San Diego.

“We’re going to see more fire, not less,” Wills said, “and these increases in wildfire occurrence and severity are going to be part of our new reality. We, as a society, must be prepared to cope with these changes.”

“Abrupt climate change can lead to rapid and continuous changes that disrupt natural processes and plant communities,” reads the Declaration. “Managers are not safe in assuming that tomorrow’s climate will mimic that of the last several decades.

“Increased temperatures are projected to lead to broad-scale alteration of storm tracks thereby changing precipitation patterns. Historical data show that such changes in past millennia were often accompanied by disruption of fire regimes with major migration and reorganization of vegetation at regional and continental scales.

“Some believe that the impacts of climate change may already be emerging as seen in more frequent outbreaks of very large fires, widespread tree die-offs across the southwest United States, expansive insect infestations in the Rocky Mountains, and more rapid and earlier melting of snow packs globally.

“Currently, we are observing wildland fire conditions previously considered rare, such as extreme wildfire events (e.g. high heat release and severe impact to ecosystems), lengthened wildfire seasons, and large-scale wildfires in fire-sensitive ecosystems (e.g. tropical rain forests and arid deserts),” the Declaration continued. “Research indicates that climate change has, in part, caused these trends. Therefore, we are deeply concerned that wildfire conditions will only become exacerbated by further climate change.”

In the western United States, researchers recently confirmed an increase in fire season duration with large forest fires starting both earlier and later in the year than in the recent past. “These changes are correlated with earlier spring snowmelt dates,” the Declaration said. “The ecological impacts are wide-reaching because of the high severity of these fires burning through heavy fuel loads. With global temperatures projected to rise throughout this century, we expect increases in fire season length and fire size.

“As temperatures increase, we should expect fire to become a primary agent of vegetation change in many natural ecosystems. As such, we will likely see wholesale conversions of habitats from one type to another. For example, temperate dry forests could be converted to grasslands or moist tropical forests could be converted to dry woodlands.

“High-severity fires could also eliminate entire forests and then seedling reestablishment could be hindered by a new and unsuitable microclimate. Plant and animal species already vulnerable due to human activities, would be put at greater risk of extinction as their traditional habitats become irreversibly modified by severe fire. Finally, extreme wildfire events and a lengthened fire season would greatly increase the risk to human lives and infrastructures, particularly within the wildland urban interface,” the Declaration concludes.

Wills said, “What’s important about the Declaration is that we need to change our approach to managing wildland fire. Traditional approaches of suppression need to adapt to those changes in vegetation and resulting changes in fire regimes. There is a direct relationship between changes in climate and changes in the way fires behave and we need to make a corresponding change in our fire management.”

The Fire Congress will consist of lectures, field trips, workshops, posters, and exhibits showcasing new products, technology, and tools on the leading edge of international fire science and fire policy and is likely to attract 3,000 attendees.

For more information, visit: http://www.fireecology.net.