Human-induced climate change has doubled forest fire damage in the West over the past 30 years, says a study published online early by the journal PNAS. But human effects on fire extend far beyond climate.
The paper, which compared climate models to fire data across western U.S. forests, has been burning up news sites with its findings. It pins 55 percent of fire-season fuel aridity — the dryness that turns wet wood to kindling — to human-caused climate change.
But fire historian Steve Pyne of Arizona State University worries that, by snubbing other human-nature links, the research might have missed the forest for the trees.
“We should begin with the assumption that what we’re looking at here is the interaction of these two, instead to trying to say, ‘Well, this is the driver’ — and, in some ways, identify this driver because we can measure it — when in fact it’s a lot messier system," said Pyne.
This need — to study only what can be measured or modeled — meant the research left out key fire factors, such as upticks in human ignitions, variations in fire policies, changes in land use and — as University of Arizona dendrochronologist Steve Leavitt points out — shifts in plant life.
“If you do have a fire, you don’t necessarily get the same species of tree growing back in the place where you had the burns,” he said.
As for Pyne, he sees these other roots as causes for concern, but also for hope.
“There are lots of things we can do. We can learn to live with fire; we can begin selectively and shrewdly finding points to intervene," said Pyne.
