As fires propagate throughout the US west on the heels of record heatwaves, experts are warning that the region is caught in a vicious feedback cycle of extreme heat, drought and fire, all amplified by the climate crisis.
Firefighters are battling blazes from Arizona to Washington state that are burning with a worrying ferocity, while officials say California is already set to outpace last year’s record-breaking fire season.
Extreme heatwaves over the past few weeks – which have smashed records everywhere from southern California to Nevada and Oregon – are causing the region’s water reserves to evaporate at an alarming rate, said Jose Pablo Ortiz Partida, a climate scientist for the Union of Concerned Scientists, a non-profit advocacy group. And devoid of moisture, the landscape heats up quickly, like a hot plate, desiccating the landscape and turning vegetation into kindling.
“For our most vulnerable, disadvantaged communities, this also creates compounding health effects,” Ortiz said. “First there’s the heat. Then for many families their water supplies are affected. And then it’s also the same heat and drought that are exacerbating wildfires and leading to smoky, unhealthy air quality.”
In northern California, the largest wildfire to hit the state this year broke out over the weekend and has so far consumed more than 140 sq miles (362 sq km). The Beckwourth Complex grew so fast and with such intensity that it whipped up a rare fire tornado – a swirling vortex of smoke and fire.
Meanwhile, the Bootleg fire in southern Oregon engulfed more than 240 sq miles (621 sq km) and has doubled in size three times over the weekend. After the fire disrupted electric transmission lines, California’s power grid operator asked residents to conserve electricity on Monday evening to avoid brownouts.
“The fire behavior we are seeing on the Bootleg fire is among the most extreme you can find and firefighters are seeing conditions they have never seen before,” Al Lawson, an incident commander for the Bootleg fire, said in a statement. . . . . . . . . . . . . . . . .
The intensity of the fires in California and Oregon is “not something you used to see” so early in the season, absent the strong late summer and fall winds that fuel the west’s biggest fires, said Daniel Swain, a climate scientist with the University of California, Los Angeles. The unprecedented drought gripping the west, alongside “mind-blowing” heatwaves, are fueling extreme fires this year, Swain said, adding that the extreme conditions could set the stage for “considerably worse” fires in late summer and fall. Historically, September and October have been the worst months for megafires in California.
This week, smoke from the various fires in the west is expected to carry across the country, reaching up into Minnesota and bleeding into central Canada. Forecasters are predicting that the intense high temperatures that came last weekend as a heat dome smothered the west are likely to ease later this week, and the south-west is likely to see some drought-relieving rain throughout the week. Still, large swaths of the west, including California, the Pacific north-west, and the northern Rocky Mountain region are expected to face dangerous conditions, including the possibility of dry lightning and strong winds.
In Salton City, California, a receding waterline shows the drought’s impact. Photograph: Aude Guerrucci/Reuters
“All of these fires bear some sign of climate change, which is really a threat multiplier,” said Faith Kearns, a scientist at the California Institute for Water Resources. “We have always had fires in the west. The landscape is in many ways forged in fire. But the intensity of the fires we’re seeing now, that some of these fires are happening so early in the summer, those things are definitely concerning.”
For climate scientists and fire ecologists who have been warning for decades that global heating would bring on hotter heatwaves, drier droughts and more fire, “it can be really demoralizing and very frustrating to find ourselves here,” Kearns said. “Maybe this year will finally be the one to heighten our sense of just how vulnerable we are.”
Whether that leads to big changes in the public’s will to address the climate crisis and adapt to a landscape that is expected to burn with increasing intensity “remains up in the air”, she said.