The unusual December flames that swept through Boulder County, Colorado, at an alarming rate this week may not be uncommon in the future, warn volcanic fire experts, as climate change sets the stage for an increase.
Wildfires do not occur historically in winter, especially in areas such as Boulder County, where the soil is often wet with snow.
But in recent months, Colorado has experienced a severe drought. From July 1 to December. 29, 2021, Denver recorded its low rainfall over an inch, with snow falling at record low levels. At that time, Boulder, which usually saw about 30 inches of snow between September and December, found one inch at a time leading up to the day of fire.
Combine that with improperly warm fall, and the soil had a much lower humidity than it usually does - creating perfect conditions for firefighting.
"Everything is kind of crispy," said Keith Musselman, an ice-cold expert and assistant professor of research at the University of Colorado Boulder. "In addition to the severe drought, one or two days of warmth can be very dry, so everything is very dry and hot."
Officials say a hurricane of 105 mph spread the blaze, quickly destroying between 500 and 1,000,000 homes and giving residents an opportunity to evacuate.
Although hurricanes of that magnitude are quite different at this time of year, they cannot be directly related to climate change, said Daniel Swain, a meteorologist at the University of California Los Angeles and the non-profit organization Nature Conservancy.
However, he said, climate change is the main reason why the earth is ready to start a fire, and other areas may have similar extensions for their veld fires.
"Apart from the time of year, the Colorado fire erupted for another reason," said Philip Higuera, a fire professor at the University of Montana. Very few burn many buildings like this.
"Unfortunately, this is one of the worst situations in the world," he said. "These are very windy events under these very dry conditions and you are actually crossing your fingers and hoping there is no man-made ignition in the wrong place."
Dealing with the problem
Solution, experts say twice: Attacking climate change through actions and dialogue between communities and homes in the long run, and in the short term, without assuming that a particular area is on fire.
"We as a society need to be aware that wherever we live in the Western vegetation it is a flammable place," Higuera said. "This can happen anywhere."
That could mean changing the way homes are built or reinforced to prevent fires, or changing the infrastructure so that power lines can be plugged in or closed during high-pressure events, he said.
Officials initially suspected that the downed power line was the cause of Thursday's fire in Colorado but later said investigations revealed it was missing. They said they were still investigating the cause.
Although fires may be common throughout the year, Swain said winter would not be the time for major fires.
"I still don't think winter will ever be the hottest season in the West," he said. "But it 's been a non-season fire, and I don't think so anymore."