In the latest example of the expanding reach of wildfires, a trio of blazes in Arizona has gutted several buildings at a national observatory, forced the evacuation of a historical monument and threatened other archaeological artifacts.
Two other wildfires are burning near Flagstaff, an area that is home to thousands of years’ worth of archaeological artifacts. Both the flames and the tools used to suppress the blaze threaten those historical remnants, which include several heritage sites and national monuments.
Wildfires in Arizona have become increasingly powerful in recent decades, posing an increased threat to areas where fire protection plans were previously less urgent. The endangerment of scientific and archaeological resources this month highlights what the nation’s forested mountainous areas stand to lose as they burn more intensely every year.
“As wildfire area gets larger and larger — the area burned and fires become more severe, all of this driven by climate change — then we have to expect that the infrastructure that we put in these areas is going to be at risk in a way that it wouldn’t have been 50 years ago,” said Don Falk, a professor of natural resources at the University of Arizona.
Although summer is just beginning, dozens of large wildfires are already active across the country — a symbol of why the U.S. Forest Service has increasingly begun to reference “fire years,” rather than fire seasons. The number of blazes recorded this year has far outstripped the 10-year average of fires usually recorded by this date, scorching more than 3 million acres, largely in the Mountain West. Nine new large wildfires were reported Tuesday, bringing the total to 45 active fires.
The Contreras Fire, which consumed parts of the Kitt Peak observatory, was sparked June 11 by lightning on a remote mountain ridge on the Tohono O’odham Indian Reservation. A heat wave and the area’s steep and rugged terrain have complicated efforts to battle the blaze, which has since spread to nearly 30,000 acres. With the wildfire about half contained, firefighters are counting on rain to tamp down the flames this week while hoping that lightning doesn’t fuel new outbreaks.
The mountaintop where the observatory is located remains evacuated and without power, limiting the ability of observatory officials to fully assess the four telescopes nearest to where the fire burned. The equipment does not appear to have been seriously damaged but may have been affected by heat, smoke or ash, said Lori Allen, director of midscale observatories at NOIRLab, which operates the observatory.
“It would set back our research, but we wouldn’t have to start over from scratch,” she said. “If we come out of this with all of the telescopes standing and with nobody hurt, I think we’ll count it a victory.”
In any case, Allen said, scientists at the observatory will likely be kept from their work for months. The electrical grid on the mountain has to be stabilized, equipment has to be cleaned of ash and fire retardant, and the instruments have to be returned to full functionality before research can resume.
The observatory staff prepared to evacuate as the fire drew closer last week, Allen said — covering optical surfaces and powering down instruments in a controlled manner. When the flames grew more rapidly than expected, the roughly 15 observatory staff members remaining on the mountain Friday left the facility.
The experience, Allen said, served as a reminder that wildfire risk is a real and present threat in the Southwest.
“It’s a time for some sober reflection on where we’re at environmentally and where we need to go,” she said.
About 300 miles north, the Pipeline and Haywire fires span more than 30,000 acres that are home to thousands of remnants of the region’s Indigenous history. The blazes forced the Wupatki National Monument, which was a center of trade and culture in the 12th century, to close June 13 due to wildfire threats for the second time this year. It reopened Wednesday after staff scrambled to protect its artifacts.
The cliff dwellings, pottery and arrowheads that dot the landscape are vulnerable to damage from both the flames and fire suppression tools, like bulldozers and shovels. Firefighters typically work with resource advisers to avoid or be more careful in locations of known artifacts and other valuable items, said Molly Hunter, a professor of natural resources at the University of Arizona and an expert in wildfires.
“There is a lot of care that can go into making sure that the fire lines aren’t going to be impacting those resources,” Hunter said. “But of course, we don’t know where all of them are, so there’s still damage that could be done.”
The heat from flames can collapse settlement walls, crack stone tools, and destroy the painted designs that indicate when a piece of pottery was made and what it was used for, said Rachel Loehman, a research landscape ecologist at the U.S. Geological Survey.
“It’s a really big deal because archaeologists use those artifacts to interpret the past,” Loehman said. “And so if you change the nature of those artifacts or you cause a loss of information, it can make it harder or impossible for archaeologists to make that interpretation.”
Coconino National Forest, where the Pipeline and Haywire fires are blazing, is well-adapted to fire. Hundreds of years ago, fires of low intensity broke out every few years, Loehman said. Indigenous communities also used controlled blazes to clear land for agriculture, control pests or cultivate plant material for baskets.
Now, Loehman said, denser forests make for more intense and energetic fires that can kill trees and ruin artifacts that have not previously endured their searing heat. The loss of those artifacts can be particularly devastating for the descendants of the Indigenous people who lived there, Loehman said.
Dramatic changes in forests, meanwhile, can make it hard for archaeologists to connect a community’s material remains with its environment, she said — another type of knowledge lost as wildfires in the region become more destructive.
“That removes our ability to understand the ecological setting in which people lived, which is really linked to the archaeological record,” Loehman said. “It just happens to be a living part of the archaeological record.”