Rethinking tactics to fight wildfires and save lives

Across the planet, human-induced climate change is making wildfires so dangerous that long-time firefighting strategies are no longer working, prompting calls for a new way of thinking about blazes, say experts. 

"Firefighters are suddenly being confronted with fires that don't play by the rules anymore," said David Bowman, a professor of pyrogeography and fire science at the University of Tasmania, who has been researching fire for four decades.

For instance, firefighters usually use calmer nighttime fire conditions when temperatures are cooler and wind dies down to consolidate and prepare for more intense daytime conditons. 

But now fires burn hot "through the night, they behave as if the night is day," said Bowman, who is worried about what the Australian fire season, which kicks off in December, will hold, given searing temperatures across the globe so far this year.

In Canada, firefighters have reported such intense fires, that water dropped by aircraft is evaporating before it even hits the ground.

The Canadian fire season runs until October, but 2023 is already the worst one on record. Thousands of fires have burned an area the size of Greece — 10 times as much as last year. The fires have generated hundreds of millions of tons of CO2, roughly equivalent to what the Netherlands emits in a year. 

Climate change increasing fire risk?

There is no one cause of the fires the world is seeing from Maui to Greece to Canada. The reasons for wildfires are complex. Land use changes and poor forest management play a part in worsening fires.

But human-driven climate change is playing a role and is increasing fire risks in many parts of the world, according to Mojtaba Sadegh, an associate professor in civil engineering at Boise State University in the northwestern US state of Idaho. 

More hot days, drought and declining rainfall can exacerbate the severity of fires because soil is drier and parched vegetation makes perfect kindling. 

"The dry, hot, windy conditions that are a recipe for large fires are getting more and more frequent in many regions," Sadegh said. "Dryness leads to more hotness, hotness leads to more dryness."

And more intense and larger fires generate so much heat, they are creating their own weather patterns, affecting wind direction and causing the fire to spread more quickly, as was the case with a massive blaze in the US state of Oregon in 2021.

Some studies have found that wildfire seasons have lengthened due to planetary heating. In Mediterranean climates, for example, the time between the last spring rainfall and the first fall precipitation is becoming longer, creating dangerous conditions when winds start fanning the flames. 

These conditions don't always lead to fires, but longer periods of hot, dry weather increase the risk of fire with each passing day. The blazes themselves are often ignited by lightning strikes, electrical faults and in some cases arson.

Arms race with fire

The new breed of fires has fostered new approaches that favor preparedness and resilience over the previous mantra of concentrating on extinguishing fires.

Fire scientist Bowman said politicians can be tempted by big-ticket technological purchases, such as aerial waterbombers, to put out blazes, but these are expensive to operate, damaging to soil, and are often ineffective due to fog or air disturbances.

"You get a situation where the fires can become so intense they can't be fought. There's no technology that exists anymore," Bowman said, who has an escape plan that involves a bicycle and a sea kayak if his home city of Hobart on the island of Tasmania goes up in flames.  

He likened big-ticket measures to building expensive hospitals, rather than taking preventative actions like reducing smoking rates and getting people to eat healthily.

The fire equivalent of eating healthily

Sadegh of Boise State said more stringent building codes can protect homes against inevitable fire risks.

Roofs and porches built with flammable materials are especially vulnerable to catching fire from far-reaching embers. Building homes further apart and clearing vegetation before fire season starts can slow the spread of fire, said Sadegh. 

Sadegh said the fire in Hawaii's Lahaina, which killed more than 100 people, might have been far less destructive had the surrounding land been cleared of invasive grasses that had taken over abandoned agricultural land.

The Lahaina fire demonstrated the vulnerability of infrastructure to fire damage, said the civil engineer, who is focused on extreme weather hazards. As people tried to flee the danger, they were also hampered by poor evacuation infrastructure.

"A lot of people burned in their cars as they were trying to flee the fire," Sadegh said. "We have tornado shelters in parts of the Eastern United States. Is it time for us to think about fire shelters in communities that are hard to evacuate?"

The Australian state of Victoria now has government regulations on private fire shelters, which can look like underground bunkers.

Preemptive burns

Last year, the United States Department of Agriculture's Forest Service issued a new strategy for confronting wildfires, calling for a "paradigm shift in land management practices."

It found that about a quarter of the contiguous United States is at moderate to very high risk from wildfire, partly due to a longtime focus on extinguishing natural fires. Wildfires can have ecological benefits because they clear out dead organic material and other dense foliage that would otherwise be primed to burn. 

The new US Forest Service strategy calls for vastly increased numbers of prescribed burns and forest thinning, which mimic the functions of naturally occurring fires, while also counteracting the growing risk of out-of-control blazes. 

The approach involves deliberately burning during mild conditions to control the level of flammable vegetation. Indigenous people in Australia and North America were carrying out the practice of "controlled burning" long before European colonization.

But even this strategy faces problems. A warming climate has reduced the number of mild days available for firefighters to carry out controlled burns. And in extreme conditions, fuel reduction can have a very limited effect as fires spread in the tree canopy rather than the undergrowth.

Canada does have a policy of letting fires burn out on their own in remote places where no humans are at risk but the vast amounts of smoke thrown up by the current blazes are dangerous. Smoke from the Canadian fires triggered air quality alerts all down the eastern US coast this season.  

The one solution that all researchers and policymakers seem to be unified on is that the carbon emissions warming the planet — and that are largely emitted by burning fossil fuels — must be slashed urgently. 

But even if humanity achieves its emissions goals, wildfires will still increase, according to a 2022 report by the United Nations Environment Program. 

"We must learn to live with fire," wrote the authors. 

Edited by: Jennifer Collins