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Computer models indicate that wildfires will become more frequent in temperate regions as the climate changes over the coming decades

As wildfires burn across wide stretches of Colorado and New Mexico, we’ve got some more bad news: the most comprehensive wildfire modeling project to date indicates that fires will become considerably more frequent in the United States as our climate changes over the coming decades.

According to a paper published yesterday in Ecosphere by researchers from the University of California at Berkeley and elsewhere, climate change is projected to disrupt fire patterns around the world. Most temperate areas are likely to experience more frequent wildfires due to mean temperature increases, while other regions will see fewer fires because of increased rainfall. Residents of the western United States in particular—and most temperate regions, including the entire United States and Europe as a whole—are likely to experience more frequent wildfires, the computer models project.

“Most of the previous wildfire projection studies focused on specific regions of the world, or relied upon only a handful of climate models,” said study co-author and Texas Tech University professor Katharine Hayhoe in a press release. “Our study is unique in that we build a forecast for fire 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 models incorporated more than a decade of satellite-based fire records and climate observations to determine which environmental factors are most responsible for increasing or decreasing the risk of wildfires. They then combined these factors with 16 different established global climate models to predict how climate change would affect the frequency of fires on a large scale. The study projected trends over two separate periods, 2010 to 2039 and 2070 to 2099.

The projections for the time period 2070-2099 show a greater risk of fire in temperate areas, and a reduced risk in the tropics. Image courtesy of the University of California at Berkeley

The scientists were most surprised by how quickly fire patterns could change. ”In the long run, we found what most fear—increasing fire activity across large parts of the planet,” said lead author Max Moritz of Berkeley. “But the speed and extent to which some of these changes may happen is surprising.” The study indicated that some disruption in fire patterns is likely to occur within the earlier period studied—that is, over next 30 years.

Although the various models used disagreed about future fire trends in many areas, they were unequivocal about places such as the western United States, which showed an increased risk of fire across nearly all scenarios. ”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,” Hayhoe said.

Wildfires impact both human societies and natural ecosystems—and can often upset a delicate balance between the two. The researchers noted that Southeast Asia is home to millions of people who rely on forests for their daily cooking fuel, while in the United States, wildfires already affect a range of livelihoods. Across all ecosystems, more frequent fires can cripple native plant and animal species that are already at risk due to habitat loss, while simultaneously uprooting homes and communities.

The research team recommends that conservation and urban development experts include long-term fire trends in planning and risk analysis, but note that in many cases, we must simply learn to coexist with more frequent wildfires.

Of course, the study makes one key assumption: that current trends in climate change are sure to continue. Instead of pouring more resources into fighting fires in the year 2039—and suffering the consequences of fire destruction in places where we can’t fight them—we do have the choice to prevent the risk of more fires right now.

It’s hard to mentally link current activities such as greenhouse gas emissions with wildfires that will burn across the country decades from now, but that connection is just what this study established. ”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,” Payhoe said.