Fire risks to increase in some regions of the world

based upon consistent projections across 16 different climate models combined with satellite data, which gives a global perspective on recent fire patterns and their relationship to climate.”

The fire models in this study are based on climate averages that include mean annual precipitation and mean temperature of the warmest month. These variables tend to control long-term biomass productivity and how flammable that fuel can get during the fire season, the researchers said.

Variables that reflect more ephemeral fluctuations in climate, such as annual rainfall shifts due to El Niño cycles, were not included because they vary over shorter periods of time, and future climate projections are only considered representative for averages over time periods of 20-30 years or longer, the authors said.

The release notes that the study found that the greatest disagreements among models occur for the next few decades, with uncertainty across more than half the planet about whether fire activity will increase or decrease.

Some areas of the world, such as the western United States, however, show a high level of agreement in climate models both near-term and long-term, resulting in a stronger conclusion that those regions should brace themselves for more fire.

“When many different models paint the same picture, that gives us confidence that the results of our study reflect a robust fire frequency projection for that region,” said Hayhoe. “What is clear is that the choices we are making as a society right now and in the next few decades will determine what Earth’s climate will look like over this century and beyond.”

“We need to learn how to coexist with fire,” said Moritz.

Study co-author David Ganz, who was director of forest carbon science at the Nature Conservancy at the time of the study, noted the significance of the findings for populations that rely upon fire-sensitive ecosystems.

“In Southeast Asia alone, there are millions of people that depend on forested ecosystems for their livelihoods,” he said. “Knowing how climate and fire interact are important factors that one needs to consider when managing landscapes to maintain these ecosystem goods and services.”

The researchers noted that the models they developed focused on fire frequencies, and that linking these to other models of fire intensity and vegetation change are important next steps.

The Natural Sciences and Engineering Research Council of Canada, the U.S. Forest Service, the National Science Foundation and The Nature Conservancy helped support this study.

— Read more in Max A. Moritz et al., “Climate change and disruptions to global fire activity,” Ecosphere 3, no. 6 (June 2012)