By on May 24, 2017

JACKSON HOLE, WY – The clear blue sky is slowly gobbled up by rolling dark thunderheads. Thick squalls of rain and gusts of wind intermittently pummel the valley. A bright streak of lightning splits the sky, striking a tall, dead tree on a densely-wooded ridge in the Tetons. Will a large-scale wildfire ensue? This is fire season in Jackson Hole.

Fire is a force for the vitality and resilience of the Greater Yellowstone Ecosystem. However, as climate change has caused shifting patterns in weather and widespread droughts throughout the West, fires are behaving differently. There’s no clear and easy explanation for the way these climate shifts are impacting wildfires. Rather, there are interrelated factors that have the potential to combine and ignite fires that are hotter, faster moving and more dangerous to the firefighters attempting to manage them, and the people who live in their paths.

In the face of the changing climate, accidental fires can prove calamitous, and the potentially more widespread scope of a fire that occurs in extreme conditions. What’s more, the changing frequency and dynamics of large-scale fires clearly illustrate the impact that human-driven climate change is having on the planet.

Janus-faced fires: first, the good

The smoky summer of 2016 kept firefighters busy. Wildfires blazed for much of the season. Many small fires simmered in the backcountry, and a few large-scale fires grabbed headlines. The Cliff Creek, Lava Mountain and Berry fires impeded travel to the north and south of Jackson Hole, and swept unnervingly near to homes and businesses. The community wondered: Is this the new normal?

Complaints swirl about suppression efforts, that they should be more aggressive, and fires like the Berry fire should have been extinguished as quickly as possible. Using logging as a mitigation tactic is another idea. Others recognize the inherent ecological value of fire, but worry about the impact of the changing climate on the size and frequency of blazes.

One of the most fundamental facts about fire in the Rocky Mountains is that it is not only natural, but critical. In other words, it’s not benign, but profoundly necessary and beneficial to the landscape.

“Lands managed by the Forest Service often have vegetation and wildlife habitat that require fire to remain healthy and functioning watersheds,” explained Bridger Teton National Forest spokesperson Mary Cernicek.

Lodgepole pine—the most common coniferous tree found in Yellowstone—bears two kinds of cones. One of these, serotinous cones, cannot open unless exposed to the extreme heat of a wildfire. Only when the cones reach 115 degrees can they release seeds into the newly-blackened soil, a perfect spot to sprout the next generation of conifers. A wide variety of grasses and wildflowers also flourish in recently burned areas due to the nutrient-rich soil and little competition for sunlight.

Plants aren’t alone in benefitting from fire. Many animals depend on the ways fire reinvigorates the landscape. Fire expert, ecologist, and author George Wuerthner explains that most people underestimate how many species rely on fire. “There are a lot of wildlife and plants that live in mortal fear of green forests because they’re so dependent on the dead trees that result from a forest fire or beetle kill. If you’re a woodpecker, you’re celebrating if there’s a wildfire,” he said.

More than 45 percent of birds in the Rocky Mountains utilize dead trees, either standing or fallen, at some point in their lifecycle, Wuerthner noted. Similarly, elk, deer and bison are drawn to the grasses that sprout in the years after a fire.

Trees that are killed by fire continue to play an important role in the ecosystem beyond habitat for birds and insects as well. Fallen snags stabilize the earth, slowing erosion and encouraging the growth of grasses, flowers and brush. Those that fall into streams and rivers serve similar purposes—they slow the water’s current, create ideal habitat for aquatic insects and fish, and mitigate streambank erosion. Of course, it’s not hard to fathom the expanding rings of positive impact from healthier waterways.

Ospreys and eagles benefit, as do waterfowl and riparian mammals like beavers, muskrat and otters. All the way up to bears, wolves and other predators, it’s nearly impossible to find a species that does not, in some way, reap benefits from seasonal fires.

Too much of a good thing

In May 2016, geographers John Abatzoglou and A. Park Williams from the University of Idaho and Columbia University released a study on whether human-driven climate change has influenced wildfire patterns across the country.

“Widespread increases in fire activity, including area burned, number of large fires, and fire-season length, have been documented across the Western United States and in other temperate and high-latitude ecosystems over the past half century. Increased fire activity across Western U.S. forests has coincided with climatic conditions more conducive to wildfire,” the study reads. In other words, when they tracked climate shifts and compared them to the size and duration of wildfires, the relationship was clear. Human-caused climate change is contributing to larger fires that burn longer.

“We estimate that human-caused climate change contributed to an additional 4.2 million [hectares] of forest fire area during 1984 to 2015, nearly doubling the forest fire area expected in its absence,” the study noted.

Of course, there are other factors at play in how and where forests burn. The complicated history of fire suppression in certain regions has impacted how fuels have accumulated, and interventions such as logging and prescribed burning have influenced some areas as well. However, the message of the study is clear: Climate change is changing fires on a continental scale.

Researchers in Yellowstone agree. Ann Rodman, branch chief for Physical Resources and Climate Change, explained: “Climate change is no longer a vague threat in our future; it is the changing reality we live with, and requires continuous planning and adaptation. Temperatures are warmer, snowpack is decreasing, springtime arrives sooner, and the growing season is longer.”

GYE is experiencing measurable changes in these areas and more. In the paper Trends in Yellowstone’s Snowpack that Rodman penned alongside Dr. Mike Tercek and Dr. David Thoma, she noted troubling trends of higher temperatures and lower levels of snowpack over the last few decades.

“Intuitively, snowpack declines could be attributed to either increased temperatures or reduced precipitation, or a combination of the two. It also seems possible changes in temperature and precipitation might be due to a combination of both natural and human causes,” the paper reads. However, when the team combined meteorological and tree-ring data from the past 800 years, its conclusion was that “Natural cycles are important, but they are not the primary influence of snowpack levels. Results from other research support our conclusion that long-term snowpack declines are caused by temperature increases and the pattern is found across the Western U.S. More importantly, these temperature increases are moving in one direction instead of cycling.”

In other words, the trend is obvious. “We are confident in saying the long-term forecast in Yellowstone calls for less snow. There may be a few decades-long bumps and flat places in the trend, but the overall picture of a declining staircase is clear,” the study noted.

Research from the National Oceanic and Atmospheric Administration supports this notion: “Global surface temperature in 2016 was the warmest since official records began in 1880. It was the third year in a row to set a new heat record, and the fifth time the record has been broken since the start of the 21st century.”

A great deal of research in the national parks has explored the impact of climate change on the area. The results all point to the same conclusion: less moisture,—both in the form of wintertime snow and summertime rain—as well as overall increases in temperature, are creating the ideal context for large, fast-moving fires.

Cernicek confirmed that the Bridger-Teton National Forest has observed similar trends, and is trying to adapt accordingly. “We are certainly seeing longer duration fires, not only on the Bridger-Teton, but also in the Intermountain West,” she said.

The consequences of more frequent, widespread fires, scientists warn, is a dramatically different landscape than the Greater Yellowstone Region people know today.

Dr. Corinna Riginos is a local scientist who has been studying climate change’s impacts on GYE. Along with Teton County Commissioner Mark Newcomb, she co-authored the seminal 2015 report, The Coming Climate. Published by the non-partisan think tank the Charture Institute, it is the first study to explore the effects of climate change, on natural and social science levels, in the Teton region.

“The potential for much more frequent, large fires would radically alter the ecosystem as we know it,” Riginos told PJH on the heels of the report’s release. “We are not just talking about a few species going locally extinct or needing to shift to higher elevations; we are talking about fires so frequent that they could wipe out forests in most parts of the region.”

Such massive, frequent fires would not only convert forested areas into grasslands and shrubs, decimating the habitats of species such as moose and mule deer, but the economic impacts would be far-reaching. Along with the cost of fighting fires, tourism would plummet, much the way it did following the Yellowstone fires, the report concluded.

The price tag for mitigating and suppressing wildfires across the nation is rising right alongside annual temperatures. While there are many agencies that contribute to preventing and fighting wildfires, the Forest Service is a telling example of shifting needs and priorities.

“The nation’s ability to protect its forest and grassland resources is now at risk due to drought, invasive species, uncharacteristically severe wildfires, and uncharacteristically severe outbreaks of insects and disease, all exacerbated by a changing climate,” notes the Forest Service budget summary.

“For the first time in its 110-year history, the Forest Service is spending more than 50 percent of its budget to suppress the nation’s wildfires. As the costs of fighting wildfires have grown, the agency has shifted staffing and resources from non-fire to fire-related programs.”

In 2017, $40 million will be dedicated to the Collaborative Forest Landscape Restoration Program, which includes fuel management projects across the nation. An additional $384 million will go towards protecting homes and communities in the Wildland Urban Interface, meaning they border forests or grasslands that are susceptible to fire.

Finally, a staggering $873.9 million is tagged for fire suppression: an increase of $62.9 million from last year. Forest Service officials warn that spending ever-increasing amounts on fire management saps funding from other important programs.

“As fire seasons have worsened, our firefighting costs have routinely exceeded our annual budgets for fighting fire, forcing us to ‘ borrow’ funds from non-fire programs,” the budget summary concludes. “Dollars taken from non-fire programs for fire suppression interrupt projects and activities that preemptively reduce the risk of catastrophic fires, restore forest health, protect communities, and deliver a multitude of other values.”

The science behind the perfect storm

“Generally, our fires are more controlled by the weather and the climate than by the fuels,” Wuerthner said. It’s a point that he works hard to drive home in his writing and presentations. “If you don’t have the right conditions for a fire, it just won’t go anywhere.”

Climate factors, he explained, are bigger, overarching factors like regional droughts. Weather is the more immediate context surrounding a fire, including wind direction and speed, relative humidity and precipitation. The mere presence of burnable fuel (like trees) doesn’t immediately translate into fire in every scenario. It’s a specific kind of fuel that burns well in forest fires, known as “fine” or “light, flashy” fuel. Grass, brush, and small branches all fall into this category. Wuerthner gives the example of a campfire: if you try to start a thick round of wood, it’s difficult. However, add some kindling or twigs, and you’ll quickly make progress. The same principles of thermodynamics apply in a wildfire.

Though it may seem counter-intuitive, green conifers burn better than dead ones. Small branches and needles are packed with flammable resins, and during hot and windy summers, can lose most of their water content. Dry, sap-filled fuels go up quickly and easily. Think of a Christmas tree a few weeks after the holiday—it still appears green, and is holding on to most of its needles, but is very dry and would easily light.

Just how susceptible a lodgepole pine forest is to fire is surprisingly dynamic, a fact that was revealed through studies in Yellowstone National Park following the 1988 fires.

“The susceptibility for fires, especially in lodgepole pine forests, goes in a cycle,” Wuerthner said. “The susceptibility rises over time, then decreases, and then rises over time again. How it works is this: Initially, after you have a fire, and the trees are killed, the chances of the area reburning are actually pretty small for a while. The reason is that once the needles and small branches are off the trees, you’ve lost the fine fuels.” Then, as the seeds released by the serotinous cones grow into young trees, they tend to be densely-packed. This collection of fine fuels increases the forest’s susceptibility to fire for a few years.

To see an example, drive to the south entrance of Yellowstone. Swaths of the hillside populated by lodgepole regrowth since the fires of 1988 burned again in last fall’s Berry fire. Needles and twigs gone, the black spindly trunks of 20-something trees seem as numerous as bristles on a brush.

As time rolls on, as the trees grow, a few changes make them less vulnerable to burning. Competition for resources thins the trees, and their taller stature both moves their fine fuels away from the ground as well as blocks light for grasses and shrubs (fine fuels) on the forest floor. For the following couple of centuries, Wuerthner explained, their susceptibility is low. Eventually, as the trees start to die and fall, they open up the canopy and return fuels to the forest floor, again increasing the area’s chances of a fire.

An even more critical factor that influences whether a lightning strike or other ignition will produce a fire is the weather. It’s not difficult to understand why hot, dry, windy conditions contribute to large fires. The opposite—damp, cool weather, will help most wildfires self-extinguish. Heat and wind draw moisture out of plants, and as anyone who has ever tossed green leaves on a campfire knows, dry plants burn more rapidly.

Wuerthner highlights how low moisture in trees and grasses contributed to the area’s large fires nearly 30 years ago. “In Yellowstone in 88, the internal moisture of some of the trees got down to 1 percent, and kiln-dry lumber is 12 to 15 percent. In other words, if you went to a lumberyard, that would be less burnable than the trees were in Yellowstone, especially because they had more fine fuels and resins.”

So, if the lightning that strikes the ridge occurs on a hot and windy afternoon, following two weeks of no rain, its chances increase significantly. If it lands among green lodgepole that are susceptible to fire, and have been dried out both by long-term climate and immediate weather conditions, it could become a very large fire indeed.

Forecasting flames

As NOAA observed, 2016 shattered temperature records for the third consecutive year, so it wouldn’t be surprising to see the warming trend continue in 2017. However, it’s unclear what the winter’s abundant snowfall will mean for fires in the coming season.

Wuerthner thinks fires in the region may not be as expansive as last year. “Given that there has been a significant amount of precipitation in the form of snow, the prediction I would make is that we probably won’t have a lot of large fires this year. With the caveat: that could change quickly if there was a month of really above-average temperatures where the snow melted off rapidly and temperatures stayed high.” However, there is a caveat.

Should spring warming occur slowly, and precipitation continue at regular intervals over the summer, there’s a chance that fine fuels won’t dry out as quickly or thoroughly as they did in 2016. However, a hot and dry month would be all it takes to change that. The damp spring could translate into rapid and dense growth of grasses and shrubs, creating a fuel load like last summer.

Cernicek agrees. “It is still too early to predict what the 2017 fire season will look like. Fire managers will be paying careful attention to fuel moisture levels as the season progresses.”

Cernicek also says BTNF has been keeping an eye on the same trends throughout the region. “Research continues to show that we can expect to see longer fire seasons, bigger wildfires, and more extreme fire behavior. We do know that managing wildfires is inherently complex and challenging and it will continue to be so. As last year showed, this is compounded by many factors including longer fire seasons, bigger wildfires burning more land on average each year, and the presence of homes and communities in the wildland urban interface area.”

On a larger scale, other factors have the potential to influence prevention and management of wildfires in the West.

President Trump’s support of extraction industries is likely to open up more opportunities for the logging industry in forests that were previously off-limits. Advocates for the logging industry—which, by some measures, is valued at more than $200 billion—claim that selectively logging forests not only mimics the healthy impacts of fire, but also serves as a buffer tactic against future fires. For a wide variety of reasons, this simply isn’t true.

For one, the trees that logging companies remove are not the ones that burn during fires. Additionally, the removal of the tree robs the birds, insects and other species that rely on dead snags. And, logging can contribute significantly to erosion in more than one manner, as well as the spread of invasive weed species.

When it comes to preventing or slowing down a fire, logging doesn’t impact the most significant blazes, Wuerthner explained. “When the conditions are right for a big fire, it will burn through everything, thinned areas and clear cuts and such, the very fires that all this hype is about trying to stop … those large fires are the ones that the thinning and logging can’t stop.”

The main reason? Logging removes the large trees, but leaves all the grasses and shrubs behind.

Prescribed burning is a better option, but by no means perfect. Like logging, in certain situations it can actually increase the amount of light fuel in an area, contributing to more fire susceptibility instead of less. However, if done properly and maintained appropriately afterwards, these burns can help protect homes and other structures from fires. They also leave behind the beneficial structural remnants of a wildfire for the species that depend on them.

The core problem with these approaches, Wuerthner says, is those tactics might slow down or extinguish a small wildfire. However, when facing an extreme fire—a large, fast-moving blaze—it simply isn’t enough. The kinds of fires we most want to stop, the ones that burn homes and other structures, are not going to be brought to a halt by these mitigation tactics.

“The fires that thinning and logging are effective in treating are the very fires that aren’t a real threat. The ones that are a threat to homes and burn large parts of the landscape are the ones that thinning and logging isn’t effective at reducing,” he said.

Fire wisdom

In some parts of the nation, homeowners must account for potential floods or tornadoes. In the West, as temperatures rise and dry summers increasingly become the norm, more homeowners ought to plan for more frequent fires. Fire suppression, though, has also played a role in complicating future mitigation.

“We cannot, and we should not suppress every fire on the landscape. Fire is a natural and necessary element for healthy and well balanced forests. Years of fire suppression has allowed fuel to build up in forested areas and this can create a problem, such as severe and damaging wildfires that have the potential to negatively impact communities like ours,” explained Lesley Williams Gomez, in charge of North Zone Fire Prevention, Education and Information for the Jackson and Blackrock Ranger Districts.

“We need to ask ourselves as a community, how prepared do we want to be before the next unwanted wildfire?”

Regardless of the large-scale mitigation tools employed around the region, there are concrete steps that homeowners can take to keep their property safe. The Firewise Communities Program, developed by the National Fire Protection Association, helps homeowners design and prepare their properties in ways that increase the chance of making it through a wildfire. The program’s toolkit explains that fire is driven by weather, topography and available fuel.

While homeowners can’t control the first two elements, they can control the third. Debris like dead leaves and pine needles left on decks, in gutters and strewn across lawns can ignite from embers.

Fire moving along the ground’s surface can “ladder” into shrubs and low hanging tree limbs to create longer flames and more heat. If your home has flammable features or vulnerable openings, it can also serve as fuel for the fire, and become part of a disastrous chain of ignitions to other surrounding homes and structures,” the toolkit summary explained.

“For Teton County homeowners the first step is to be Firewise compliant,” Gomez said.

Firewise provides a list of important, and relatively easy, ways in which homeowners can take responsibility for the defensibility of their property. From ensuring that street names and numbers are clearly marked to clearing dense vegetation from around structures to making fire-resistant landscaping choices, there’s a great deal homeowners can reasonably accomplish.

Although it can be tempting to believe your home couldn’t be at risk of a wildfire, whether you’re perched on the edge of the Snake River or nestled into East Jackson, you’d be wrong. Many Jackson residents realized this for the first time when the Little Horsethief fire peeked over the southern ridge of Cache Creek in the fall of 2012 forcing some people to evacuate their homes.

Fire crews worked around the clock to suppress the fire and no homes were damaged in the flames.

Still, embers or firebrands can easily be swept for miles by a gust of wind, and dropped onto decks or roofs causing structures that are far from the fire to ignite.

While naturally-occurring fires are indisputably beneficial, climate change is forcing fire managers and communities to place a stronger emphasis on mitigation and resource management in the hopes of preserving the Rocky Mountain West’s iconic landscape. PJH

About Melissa Thomasma

You must be logged in to post a comment Login