Is it possible for news to be both bleak and uplifting? In the age of climate change, the answer is yes: A new study suggests that wildfires will surge for a decade (bad!), and then decline (better).
Researchers at the University of Washington and the University of California at Santa Barbara built a model of West Coast wildfires under increasing temperatures and droughts, and found that for a decade or so, fires will be formidable: The combination of many decades of few fires with hot, dry conditions creates a tinderbox.
“That first burst of wildfire is consistent with what we’re seeing right now in the West. The buildup of fuels, in conjunction with the increasingly hot and dry conditions, leads to these very large, catastrophic fire events,” said lead author Maureen Kennedy, a quantitative ecologist and assistant professor at the University of Washington at Tacoma, in a news release. “But our simulations show that if you allow fire to continue in an area, then the fire could become self-limiting, where each subsequent fire is smaller than the previous one.”
Climate change is largely to blame here. Climate largely regulates wildfires, in this case by drying out fire fuel year-to-year, and limiting new growth over the long term. At the same time, the fires themselves will burn away much of the available fire fuel. Thus, fires will not stop, but are unlikely to be mega-fires across large areas.
The model is a lesson in the perils of climate change: When the scientists run their model with a steady climate, the foliage in forest canopies remains resilient. But when extreme droughts occur, that canopy is substantially reduced.
The researchers suggest that controlled burns are the way of the future, to remove kindling and small fuels on the forest floor, as well as forest thinning, which increases moisture in the forest. “With such high density in the forest, the trees are pulling a lot of water out of the soil,” said Kennedy. “There is growing evidence that you can relieve drought stress and make more drought-resilient forests if you thin the forests, which should also help with, for example, reducing the impact of that initial pulse of wildfire.”
The study is published this week in the journal Ecosphere.