Humans are by far the main cause of wildfires

Every year in the U.S., billions of dollars are spent on wildfire suppression and risk reduction. The five federal fire agencies — Forest Service, Bureau of Land Management, National Park Service, Bureau of Indian Affairs, and Fish & Wildlife Service — spent a combined $4.4 billion (2021) and $3.5 billion (2022) in wildfire suppression alone, according to the National Interagency Fire Center (NIFC). The USFS announced in February that it would be investing nearly $500 million more in its “Confronting the Wildfire Crisis” 10-year strategy focusing on 21 priority landscapes across the West.

Despite the numerous projects and strategies billions in taxpayer monies have funded, one thing hasn’t changed over the past decade: Humans are still the main cause of wildfires — and numbers have worsened since 2014.

Air quality publication HouseFresh analyzed NIFC data from 2023 and ranked the causes of wildfires by number of occurrences. Of the recorded fires, 72.6 percent were directly caused by humans.

The bulk of last year’s wildfires were caused by debris burning and open burning, resulting in 1,302 wildfires. That is an increase from the 1,120 fires started by debris and open burning in 2022. Equipment and vehicle use, power generation/transmission/distribution, and arson were the next listed causes of wildfires in 2023 at 507, 390, and 364 respectively.

“The balance between human and natural fires has almost reversed since 2014, although the trend has not been smooth,” the HouseFresh report said. “The proportion of human-caused wildfires grew significantly in 2015, 2016 and 2020, peaking at 77.2 percent in 2020.”

How People Start Wildfires
This image is licensed under the Creative Commons Attribution-Share Alike 4.0 International License :::

To no one’s surprise, California leads the nation in number of acres burned by wildfires. The state totaled 344,878 acres burned, followed by Alaska at 295,105 acres and Arizona at 218,286 acres. Arizona led the nation, however, in the biggest increase in acres from 147,553 acres in 2022 to 218,286 acres in 2023. Southeast Fairbanks County in Alaska was the leading county in acres burned in 2023 at 141,399 acres.

“Alaska suffered the second-most land damage in 2023, despite the largest annual reduction in acres — down 2,818,744 acres from 3,113,849 in the previous, record-breaking year,” the report says. “Unfortunately, many places where fires burn are hard to reach; at the same time, permafrost and surface fuels make Alaska’s wildfires particularly pollutive.”

~ The full report’s posted on the HouseFresh website.

Every year in the U.S., billions of dollars are spent on wildfire suppression and risk reduction. The five federal fire agencies — Forest Service, Bureau of Land Management, National Park Service, Bureau of Indian Affairs, and Fish & Wildlife Service — spent a combined $4.4 billion (2021) and $3.5 billion (2022) in wildfire suppression alone, according to the National Interagency Fire Center (NIFC). The USFS announced in February that it would be investing nearly $500 million more in its “Confronting the Wildfire Crisis” 10-year strategy focusing on 21 priority landscapes across the West.

Canadian conservationists push emission limits for wildfire reduction

Groundbreaking research last year found around 37 percent of burned land across North America can be traced directly back to carbon emissions from 88 major fossil fuel producers and cement manufacturers. Now, environmentalists in Canada are using the research to push for change.

The study, published last May in the journal Environmental Research Letters, used climate, burned area, and global energy balance models to determine what contribution carbon emissions had on increases in vapor pressure deficit (VPD), which partially caused a rise in burned forest area in the United States and Canada. The research concluded, along with the fossil fuel link, that carbon producer emissions contributed to 48 percent of long-term VPD rise between 1901 and 2021.

canada smoke reaches Europe
Smoke from fires in Canada traversed the Atlantic Ocean and drifted over European countries including Portugal and Spain. ~ NASA image of the day for June 27, 2023

“As loss and damage from these hazards mounts, this research can inform public and legal dialogues regarding the responsibility carbon producers bear for addressing past, present, and future climate risks associated with fires and drought in the western U.S. and southwestern Canada,”  researchers said. Nearly a year later, Climate Action Network Canada advocates are using that research to advocate a new push for nationwide carbon emission limits.

June 26, 2023 Canada smoke
June 26, 2023 Canada smoke

“To cap wildfires and other climate impacts, the government must cap oil and gas emissions,” said Climate Action Network Executive Director Caroline Brouillette. “Other sectors and everyday Canadians are reducing their emissions, while for decades the oil and gas sector has increased its pollution and pushed back against every form of accountability. Further delay benefits only oil and gas executives’ pocketbooks and climate-denying politicians.”

A survey of nearly 2,000 Canadians found that nearly two-thirds of residents support a greenhouse gas emissions cap for the oil and gas industry. The survey also found that support for an emissions cap is the highest among Canadians aged 60 or older at 71 percent and only 18 percent of Canadians said the industries shouldn’t be required to limit emissions.

Such a cap would prevent 4,800 premature Canadian deaths and yield $45 billion in economic benefits, according to research projections from the Canadian Association of Physicians for the Environment. The results were attributed to projected reductions in air pollution — specifically in nitrogen dioxide, fine particulate matter, and annual ozone — if oil and gas industry emissions are capped at 45 percent below 2005 levels by 2023, which is Canada’s national climate target.

~ Full statement from Climate Action Network Canada.



Hit it hard and fast: not always best

A report published this week by researchers in Montana indicates that century-old policies to suppress wildfires as quickly as possible is actually contributing to more severe and larger fires over time. The study, published Monday in the journal Nature Communications, examines what the researchers call “suppression bias.”

They identify “suppression bias” as the consequences of knocking down low- and moderate-intensity fires: Other fires will burn hotter and scorch broader areas of forest and land, and people experience more of the most destructive fires, according to a story in the Daily Montanan. “Over a human lifespan, the modeled impacts of the suppression bias outweigh those from fuel accumulation or climate change alone. This suggests that suppression may exert a significant and underappreciated influence on patterns of fire globally,” lead author Mark Kreider, a doctoral candidate at the University of Montana, said. “By attempting to suppress all fires, we are bringing a more severe future to the present.”

On the other hand, the researchers said less suppression of lower-intensity fires might make firefighting easier in the future. Kreider authored the paper along with four other UM researchers and professors and an ecologist with the Aldo Leopold Wilderness Research Institute in Missoula.

 The Big Knife Fire outside of Arlee, Montana, on the afternoon of Sunday, July 30, 2023. (Photo by Nicole Girten, Daily Montanan)
The Big Knife Fire outside of Arlee, Montana, on the afternoon of Sunday, July 30, 2023. (Photo by Nicole Girten, Daily Montanan)

They compare suppression bias when it comes to fire management to doctors overprescribing antibiotics. “In our attempt to eliminate all fires, we have only eliminated the less intense fires (that may best align with management objectives such as fuel reductions) and instead selected for primarily the most extreme events (suppression bias) and created higher fuel loads and more ‘suppression-resistant’ fires.”

The USFS estimates that 98 percent of wildfires are fully suppressed before they reach 100 acres in size – most of them within 72 hours. In Montana, fire managers try to contain fires as quickly as possible; Gov. Greg Gianforte said last year that crews kept 95 percent of fires in Montana to 10 acres or less in 2022.

Since the late 1800s and early 1900s, policies have largely focused on protecting timber and homes from burning.

Montana’s state fire policy, adopted in 2007, specifies that minimizing property and resource loss is the priority in fighting fire and is “generally accomplished through an aggressive and rapid initial attack effort.” The policy also says that forest management including thinning and prescribed fire improves forests and that inadequate practices to reduce interface risk  could jeopardize Montanans’ constitutional right to a clean and healthful environment.

But as more development, particularly in the West, encroaches on the wildland/urban interface, a century of fire suppression and climate change has ballooned federal suppression costs from hundreds of millions a year in the 1990s to an average of $2.8 billion a year from 2018-2022 (NIFC data). Total annual acreage burned has doubled, on average, from what burned in the mid-1980s, and traditional fire seasons have increased by a month in duration, according to federal fire managers.

But the new research suggests that reducing suppression for low-intensity fires and allowing them to burn when conditions are good could mean that fire managers won’t face so many extreme fires in the future.

 A water scooper drops water on the Colt Fire in late July. (Photo courtesy Colt Fire Incident Management / Inciweb)
A Bridger Aerospace CL-215T scooper drops water on the Colt Fire in late July. (Photo courtesy Colt Fire Incident Management / Inciweb)

Last year, federal agencies updated the Cohesive Wildland Fire Management Strategy to include more prescribed burns and more fuels treatments to reduce risk of wildfires and to better account for climate change when modeling future forecasts.

Philip Higuera, a co-author of the paper and a professor of fire ecology at UM, said it may seem counterintuitive, but the research shows that accepting that more wildfires should burn (when it’s safe) should be the main takeaway. “That’s as important as fuels reduction and addressing global warming,” he said.

 ~ Thanks and a tip of the hardhat to Dick for this one. 

FIRE history, northern Great Lakes

In the northwest portion of Lake Superior is a chunk of land of about 132,000 acres that is both a geographic novelty and an International Biosphere Reserve. The Isle Royale National Park is 56 miles off Michigan’s shore and 18 miles from Minnesota’s mainland. Congress designated the 50-mile-long island as a national park in 1931, but even before that it was apparent the island’s boreal forests had a close history with fire.

2021 Horne Fire

“Official fire record keeping began in 1847, when the first General Land Office survey of Isle Royale was conducted,” according to the park’s website. “These records show 31 fires between 1847 and 1898. Data suggests fire was more frequent and/or severe in the boreal forest of the island’s northeast end, compared with the northern hardwoods of the southwest end.”

The island’s dense concentration of high-flammability trees, e.g. balsam fir, black spruce, and jack pine, heightened the risk of wildfires igniting when lightning struck. A zoologist in 1931 recognized the important role fire played in the island’s unique ecosystem, but his ideas were discarded in favor of the system-wide preference toward fire suppression.

flammable species on Isle Royale
Flammable species on Isle Royale

“In planning for improvements and facilities on Isle Royale, the National Park Service consulted with University of Michigan Zoologist Adolph Murie,” the park said. “Murie visited Isle Royale in June 1935 and recommended that no new trails be cleared by the CCC and all efforts be made to ‘guard against any sort of development which will reduce space or increase travel.’ He also recommended that forest fires be allowed to occur on Isle Royale, but this idea was rejected, and instead, an aggressive anti-forest-fire point of view was adopted.”

Isle Royale map

Officials would soon come to regret dismissing Murie’s ideas. Park historians describe the summer of 1936 as hot and dry. Hundreds of CCC enrollees arrived at the heavily logged and mined island to establish the park. On July 25, a fire started near the Consolidated Paper Company and, while a cause was never determined, the “Fire of 1936” would have the most profound effect on the natural and human history of Isle Royale compared with any other historical event.

Around 200 CCC members and loggers tried in vain to fight the fire as it grew from 200 to 5,000 acres over 10 days. The fire was reported as contained on August 4, but two spot fires that had ignited on August 2 would become much larger problems. By August 18, the three fires burned 27,000 acres before they were officially declared out after heavy rainfall.

Multiple factors contributed to the high number of acres burned in the fire, park historians said. The island’s ground was, at the time, mostly covered in highly flammable mosses. In-fighting between the park system and CCC members, including a short CCC strike when tobacco supplies ran out, likely made matters worse.

SEAT on the Horne FireThe island wouldn’t see significant wildfires again until the 2021 Horne Fire and the 2022 Mount Franklin Fire, which burned 335 acres and 6 acres respectively. In the fires’ wake, scientists and researchers hope to use the burned areas to learn more about the dynamics between fire and the island’s life.

“The area may look different, but wildfire is an agent of necessary change,” the park said. “At the site of the Horne Fire, Isle Royale ecologists now have a living laboratory, and these researchers can begin to study the relationships between fire, living things, and an island environment.”


::: more about fire ecology research on the island :::



Record-breaking fires, COVID-19, and impacts on firefighters

It’s been four years since a near-perfect storm hit the U.S. West. COVID-19 was officially declared a pandemic by the World Health Organization in March 2020, just months before the worst wildfire season in recorded history.

The interactions between wildfire and COVID-19 were large and sweeping, research in the years since has shown. The 2020 season left lasting impacts on the wildland firefighting force, both systemically and personally.

Wildland firefighters are at high risk for both COVID-19 infection and, when infected, experiencing severe illness from the virus, research published in the National Library of Medicine and Science academic journals found. Researchers in one study examined potential health and workforce capacity impacts by modeling the movement of suppression resources across the country over a season and the corresponding potential for disease spread and cascading outbreaks across wildfire incidents.

inbound and outbound firefighters on a Montana fire

The increased risk stems primarily from firefighters’ exposure to wildfire smoke, limited access to hygiene supplies, and constantly being physically near other wildland firefighters and the public.

IHC superintendents were surveyed by USFS researchers a year after the fires burned. At the beginning of the pandemic, the agency launched a wide range of new practices for hotshot crews to limit the spread of COVID-19 while also, it was hoped, improving operational efficiency. New practices included changes in pre-fire preparation, using virtual paperwork and briefings, and reformatting traditional fire camps to a more widespread layout. The USFS also created a COVID-19 Incident Risk Assessment Tool for fire managers; it measured numerous factors including camp size, mitigation techniques, and number of positive cases to estimate how at-risk each crew was.

The researchers wanted to know if superintendents were interested in maintaining any of those practices in daily hotshot crew use in the years after 2020, regardless of COVID-19. The survey found that the majority of practices contributed positively to operational efficiency in addition to crewmember safety and well-being. Most respondents preferred the ease of virtual vs. in-person paperwork and briefings, they liked having crews spike on or near the line with the full-scale ICP camp away from the fire, and they felt better physically and mentally as a result of these changes.

Wildland firefighter well-being — and proper pay — are still a major focus for the USFS post-2020 as retention becomes an increasingly worrying issue. Research conducted this year on retention found that highly skilled wildland firefighters with a high number of assigned days, payment of additional annual earnings, and gained experience throughout the firefighter’s career all had positive effects on retention. Local wages of alternative occupations in a firefighter’s local area had no significant effect on retention.

The future of wildland firefighter physical health may also see improvements thanks to technological developments stemming from COVID-19. Respiratory illnesses like coronavirus, and other long-term health risks firefighters face such as lung cancer and cardiovascular disease, may be seen in firefighters less and less as mobile respirators proceed further in development.

California fitted wildland firefighters with a mobile respirator prototype last October while they dug firelines or cut down trees with chainsaws. The results were mixed.

“Plenty broke. Hoses popped out of sockets. Straps snapped. Masks slid down sweating faces. Filters became dislodged,” Julie Johnson wrote for the San Francisco Chronicle.

During this event, firefighters from Cal Fire, L.A. County and the USFS took turns trying out several types of mask. They hiked down a slope and then back up, then pulled off their masks, sweating and breathing hard in triple-digit temps. Each round took only about ten minutes.

Firefighters shared their impressions with observers: Felt like a muzzle. Was too bulky. Too tight. It slipped off my face once I began to sweat.

Hearing one of her colleagues say “it’s better than nothing,” Cal Fire’s Sol Espinoza spoke up. “I’d rather take nothing,” she said.

The test is one of many completed or planned throughout the country as the fire agencies look to lower firefighter mortality from diseases increasingly found to be worsened through wildfire smoke inhalation. Experts have hedged their bets on technology frequently used to keep COVID-19 patients hospitalized with severe cases alive. Adaptations in the technology are still under development as researchers figure out which version might be best suited to meet the dynamic needs of firefighters in the field.

Espinoza, a firefighter with Cal Fire in San Bernardino. Espinoza said she could never imagine wearing a constrictive device that makes it harder to breathe.

Will fire be the death of California’s wine industry?

The “beating heart of the American wine industry” has had to reckon with this question since 2017 when numerous wildfires spread across northern California’s famed wine country. The Tubbs, Atlas, and Nuns fires burned hundreds of thousands of acres, caused numerous deaths, and destroyed multiple wineries and vineyards in Napa and Sonoma counties.

The total acreage burned and widespread property damage caused the 2017 wildfire season to be the most destructive in California’s history. That record-breaking year was quickly surpassed by the 2018 and 2020 fire seasons. The 2020 season, in particular, also broke burn records in the other top American wine-producing states of Oregon and Washington, and even Canada in 2021. Wildfires in the years following impacted international wine markets as well, including Italy, France, and Australia.

University California Division of Agriculture and Natural Resources

Intense flames aren’t the only threat wildfires bring to vineyards; it’s also the smoke they produce. A condition called “smoke taint” causes wine grapes exposed to smoke to acquire “unmarketable smoky, burnt, ashy, or medicinal sensory characteristics,” according to the Australian Wine Research Institute (AWRI).

The international wine industry has made it clear that it views wildfires and smoke as existential threats, along with increasing water shortages and climate change as a whole. The industry has poured billions of dollars into research on ways to stave off the industry’s wildfire-caused death rattle. Examples of recent smoke-related wine research in the U.S. include a protective spray coating for grapes, detecting the compounds responsible for the undesirable taste, and using smoke sensors in vineyards for risk assessment.

Oregon State University smoke research
Oregon State University smoke research

Agriculture-based technological developments, however, can only do so much to keep a fire-sensitive crop alive after it’s planted on fire-dependent lands. Grapes, while not technically invasive, have invaded portions of the Western United States’ lands and have largely usurped once highly forested regions where fire played an important ecological role. As prescribed fire establishes a larger role in modern Western land management practices, how long can an industry based on fruit that needs a smokeless environment survive and thrive?

The birth of California’s wine industry is well-recorded: Spanish missionaries planted the state’s first sustained vineyards in southern California during the late 1700s using grapes native to Europe — to make sacramental wine. Wine production then exploded in the northern and central parts of the state during the Gold Rush, paving the way for California’s current top grape-producing counties of Fresno, San Joaquin, and Kern.

What’s not well-recorded is how agricultural land conversions cleared millions of acres of conifer and oak forests throughout the state to make way for vineyards and other crop fields. In Napa and Sonoma counties specifically, areas now known as the pinnacle of “wine country,” modern vineyards sit on land that once supported massive oak forests culturally maintained by the area’s various Indigenous tribes.

“While almost all of the valley oaks are gone from Napa — the savannas were largely cleared to make way for intensive agriculture in the late 19th century — a few pockets remain,” a New York Times article on the Napa Valley Historical Ecology Atlas said. “The oldest trees, dating back more than 300 years, were alive when the Caymus, Napa, Canijolmano and Mayacma tribes managed the valley to produce abundant acorns, deer, salmon, and other staples.”

The clearing of these woodlands was coupled with a government-mandated suppression of cultural burning, a kind of prescribed burning Native Americans used to promote culturally significant foods and resources within a landscape. After a century of fire suppression, the USFS has begun to understand how significant cultural fire is to promoting biodiversity and creating healthy landscapes.

“Colonization and subsequent governmental fire policy mandates have disrupted the cultural use of fire, which in turn has disrupted ecological functions where those fires are absent,” USFS research said. “As society grapples with the devastating impacts of wildfires and the loss of biological diversity, many Indigenous people see traditional fire use as a key to mitigation of devastating losses while retaining traditional livelihoods associated with burning.”

In hopes of preventing future megafires, California increases prescribed burns throughout the state, including wine country. Even though research shows smoke from prescribed burns tends to be less harmful and toxic compared with smoke from wildfires, the grapes themselves don’t seem to care.

“Studies have shown that grapes need to be exposed to only a single smoke event, irrespective of the source, to become ‘tainted,’” AWRI said. “Bushfires, forest fires, planned burns, grassfires, and agricultural burns can all cause smoke taint if smoke from those fires is present in a vineyard at a high enough level for a period of time. Current research suggests fresh smoke presents the greatest risk for smoke taint, but smoke that has drifted hundreds of kilometers has also resulted in smoke taint.”

Efforts have been made for fire planners and wine producers to work together to minimize smoke’s negative effects on wine grapes, but thus far have mostly been in vain. AWRI and other wine industry researchers recommend the best time to conduct prescribed burns to limit smoke taint  is during the height of wildfire season between May and October; before grapevine flowering and after grape harvest. The “usual” best times to set prescribed burns, mid-spring or in the fall, are the most at-risk times for smoke taint in grapes.

The contradiction is clear: Grapes, at least those that winemakers don’t want smoke-tainted, can’t exist in an area with regularly prescribed burns, e.g. California.

Grapes themselves are partly to blame for this. A concept called “terroir” has been used for centuries to describe the deep ecology behind why grapes grown in different places and in different ways acquire different qualities. Everything including temperature, soil, geology, elevation, water quality, wind direction, farming practices, and the winemaking process influences grapes and, by extension, the wine made from them. Even if researchers could 100 percent prevent smoke-taint issues in wine grapes, the grapes themselves would still be affected by the inevitable changes the fire-dependent landscape will experience in years to come.

The irony is that California does have native grapes, which thrived in the state’s pre-colonized and fire-dependent forests. In fact, the global wine industry wouldn’t exist today without California Wild Grapevines, as the species was used to save the European wine industry between 1870 and 1900 when most wine grapes were killed by leaf- and root-attacking aphids. Winemakers, in a last-resort desperate bid, used Califonia Wild Grapevine roots and grafted them onto European grape varieties. The result was a plant with the root resilience of a wild grape and the desirable taste of a European grape.

California wild grapes themselves, however, were originally discredited by European colonists for being too “foxy” and not containing enough sugar. But in a state destined to have more smoke, the more fire-resilient California Wild Grape, whose burnt vines can resprout, may soon be the California wine industry’s only option. One farmer in Sonoma County agrees and is experimenting with more than 30 different native grape hybrids in response to climate change.

The global wine industry is one of stubborn tradition. The industry’s desire to find easy “solutions” to existential problems without systemic change paints a worrying picture of the role California’s vineyards play in the state’s fight against future wildfires. Winemakers can only hide behind the industry’s $70 billion price tag for so long.

There comes a point at which economic benefit is outweighed by potential ecological destruction, and the industry will soon have to decide whether it will play a role in California’s solutions to megafires or actively hamper efforts to help make the state’s landscape healthy. Winemakers in California may soon have to answer the question of “when should this industry die?”