Heat wave sparks historically unseasonable wildfires in West

The week after one of the worst heat waves in the history of the Western U.S., a series of wildfires has already broken out unseasonably early, sparking fears that this will be one of the worst fire seasons ever.

The normal wildfire season of summer and fall is approaching at a time when the entire West has experienced an unusually low winter snowpack and an early snow melt.

This has led to dryer conditions that could exacerbate fires by July and August as well as into early autumn.

Brian Harvey, an assistant professor with the University of Washington’s School of Environmental and Forest Sciences, said the areas of the country on fire are the areas experiencing the historically dry conditions.

“More than half of the current area burning is in Arizona, New Mexico, and Utah, though there are wildfires burning in other western U.S. states as well,” Harvey told The Hill. “The location of the bulk of the current fire activity lines up with most of the Southwest experiencing wildfire potential (fuel dryness) that is above normal for this time of year.”

Harvey said the area of the country that has experienced burns is larger than what was seen to this point in 2020, even before the main fire season in late August and early September.

There were 29,362 large wildfires nationwide between Jan. 1 and June 23, a 10-year high and about 4,000 above average, according to the National Interagency Fire Center (NIFC) in Boise, Idaho. The NIFC defines large wildfires as those encompassing 100 or more acres in timber, 300 acres or more in grass or brush, or requiring a large-scale firefighting response to extinguish.

In a more hopeful sign, however, the acreage burned is down during the same 10-year period.

Fires burned at an average of slightly above 1.6 million acres during this period from 2011 to 2020, according to the NIFC. This year, however, the acreage stands at 1.16 million as of Wednesday.

Still, Interior Secretary Deb Haaland on Wednesday during testimony before the House Natural Resources Committee warned that the dry conditions could become a new normal in the West , sparking wildfires over 12 months.

She told Rep. Joe Neguse (D-Colo.) that the region could face “fire years” rather than fire seasons.

The Interior Department has requested $1 billion for federal wildfire management in fiscal 2021, about $50 million more than was appropriated in fiscal 2020.

Separately, Sens. Joe Manchin (D-W.Va.), Ron Wyden (D-Ore.), Dianne Feinstein (D-Calif.) and Maria Cantwell (D-Wash.) introduced legislation in May that would require the Forest Service and Interior Department to increase the number of acres treated with controlled burns, or planned fires lit for forest management. The bill, which has been referred to the Senate Energy Committee, would also provide $300 million accounts for both agencies to conduct controlled burns.

The West is currently “unfathomably dry,” added Morgan Tingley, an associate professor of ecology and evolutionary biology at the University of California, Los Angeles.

He warned that “areas that would not normally be dry enough to burn until September or October could catch fire in July or August.”

“The dryness vastly increases the risk of new fires starting, and once they start, it intensifies the fire and makes it more likely that it might escape control and burn vast stretches of land,” Tingley said.

In Arizona alone, dozens of fires are burning as of this week, including a lightning-induced fire that has dropped ash on the northern city of Flagstaff. The national forest adjoining the city is set to fully close this week for the first time in 15 years. That fire has expanded to 31 square miles as of Tuesday, according to The Associated Press.

“As the summer continues — and particularly following the Fourth of July, which every year results in many fires from improper fireworks usage — we will see expanding ignitions into more northern states,” Tingley said.

A number of environmental factors are exacerbating the wildfire season in the West, Harvey said, but climate change is the common cause, with warming increasing the danger for fires in the American West and Southwest.

Another necessary ingredient for fires is ignition, Harvey said, but in more rural areas like the intermountain West, lightning strikes are a more common ignition source than human activity. The one common factor exacerbating fires regardless of how they started, he said, is increasing temperatures.

Both fuel and ignition for fires are more likely to occur simultaneously as temperatures increase, he said, and historical records suggest a correlation between particularly warm and dry periods and total area burned.