The wildfire season is getting longer, with many experts now talking about a wildfire year. But new research shows the way fires burn during individual days is also shifting significantly.
At night, temperatures are often cooler and the air is wetter, which gives wildland firefighters a long window to make up significant ground when trying to suppress blazes. But that pattern is breaking down, a trend driven by human-caused climate change, according to a new study.
"We do see more and more fires burning through the night," said Kaiwei Luo, lead author of the paper published by the journal Science Advances.
The team found potential burning hours — when weather conditions are conducive to active fire — grew by 36% across much of the continent over the last five decades. But those jumps were particularly pronounced in the American West.
Significant swaths of New Mexico, Arizona, Colorado, Wyoming, and Idaho are now seeing more than two additional burning hours every day, with some pockets seeing even more dramatic rises.
One of the implications, Luo said, is that fire managers should have "less confidence" in the nighttime consistently bringing relief to the fireline.
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