Wildfire, climate change and declining snowpacks are intricately connected. As temperatures rise, moisture-stressed forests can lead to bigger, hotter, longer and more frequent wildfires. In turn, wildfires can impact the amount and timing of snowmelt runoff according to a study by Anne Nolin and her Ph.D. student Kelly Gleason. The two researchers have presented new evidence showing that particles and burned woody debris from charred forests increase snowmelt and impact the hydrologic cycle — illustrated in this animation.
The producer describes this film:
“In this 13-minute film, filmmakers Stephen Most and Kevin White examine how problematic policies, fuel build-up, and climate change have endangered America’s forests. When the Rim Fire burned 256,000 acres of the Stanislaus National Forest and Yosemite National Park in 2013, it exposed the impacts that high intensity wildfires are having on watersheds, wildlife, and carbon storage. It also forged a coalition of environmentalists, loggers, scientists, officials, and land managers who are responding to this megafire and recognize the need to forestall the next one. “The Fire Next Time” is a precursor to Filmmakers Collaborative’s feaure-length work-in-progress, “MEGAFIRE at the Rim of the World.” For more information, visit megafirefilm.org.”
Scientists continue to develop evidence showing that pine beetle outbreaks do not lead to catastrophic wildfires. This should not be a shocking development to those who have been keeping abreast of the studies on the subject, including one that Wildfire Today first covered in 2010 (Firefighters should calm down about beetle-killed forests).
In a soon to be published paper, University of Colorado Boulder researcher Sarah Hart determined, “The bottom line is that forests infested by the mountain pine beetle are not more likely to burn at a regional scale. We found that alterations in the forest infested by the mountain pine beetle are not as important in fires as overriding drivers like climate and topography.”
The CU-Boulder study authors looked at the three peak years of Western wildfires since 2002, using maps produced by federal land management agencies. The researchers superimposed maps of areas burned in the West in 2006, 2007 and 2012 on maps of areas identified as infested by mountain pine beetles.
Western U.S. forests killed by the mountain pine beetle epidemic are no more at risk to burn than healthy Western forests, she found. Results that fly in the face of both public perception and policy.
The area of forests burned during those three years combined were responsible for 46 percent of the total area burned in the West from 2002 to 2013.
Co-authors on the new study include CU-Boulder Research Scientist Tania Schoennagel of the Institute of Arctic and Alpine Research, CU-Boulder geography Professor Thomas Veblen and CU-Boulder doctoral student Teresa Chapman.
The impetus for the study was in part the severe and extensive native bark beetle outbreaks in response to warming temperatures and drought over the past 15 years that have caused dramatic tree mortality from Alaska to the American Southwest, said Hart. Mountain pine beetles killed more than 24,700 square miles of forest across the Western U.S. in that time period, an area nearly as large as Lake Superior.
“The question was still out there about whether bark beetle outbreaks really have affected subsequent fires,” Hart said. “We wanted to take a broad-scale, top-down approach and look at all of the fires across the Western U.S. and see the emergent effects of bark beetle kill on fires.”
Previous studies examining the effect of bark beetles on wildfire activity have been much smaller in scale, assessing the impact of the insects on one or only a few fires, said Hart. This is the first study to look at trends from multiple years across the entire Western U.S. While several of the small studies indicated bark beetle activity was not a significant factor, some computer modeling studies conclude the opposite.
The CU-Boulder team used ground, airplane and satellite data from the U.S. Forest Service and the U.S. Geological Survey to produce maps of both beetle infestation and the extent of wildfire burns across the West.
The two factors that appear to play the most important roles in larger Western forest fires include climate change — temperatures in the West have risen by about 2 degrees Fahrenheit since 1970 as a result of increasing greenhouse gases — and a prolonged Western drought, which has been ongoing since 2002.
“What we are seeing in this study is that at broad scales, fire does not necessarily follow mountain pine beetles,” said Schoennagel. “It’s well known, however, that fire does follow drought.”
The 2014 Farm Bill allocated $200 million to reduce the risk of insect outbreak, disease and subsequent wildfire across roughly 70,000 square miles of National Forest land in the West, said Hart. “We believe the government needs to be smart about how these funds are spent based on what the science is telling us,” she said. “If the money is spent on increasing the safety of firefighters, for example, or protecting homes at risk of burning from forest fires, we think that makes sense.”
Firefighting in forests that have been killed by mountain pine beetles will continue to be a big challenge, said Schoennagel. But thinning such forests in an attempt to mitigate the chance of burning is probably not an effective strategy.
“I think what is really powerful about our study is its broad scale,” said Hart. “It is pretty conclusive that we are not seeing an increase in areas burned even as we see an increase in the mountain pine beetle outbreaks,” she said.
“These results refute the assumption that increased bark beetle activity has increased area burned,” wrote the researchers in PNAS. “Therefore, policy discussions should focus on societal adaptation to the effect of the underlying drivers: warmer temperatures and increased drought.”
The High Country News has an interesting article about the lengthening of the wildfire seasons. Below is an excerpt:
…For local residents, [the 7,000-acre Round Fire north of Bishop, CA on February 10, 2015] drove home a message Westerners may finally have to get used to: Fire season isn’t just confined to the months of July and August anymore, or even May through September. Over the last four decades, the season across the West has gotten two and a half months longer. Last year, rare January fires swept across southern California. And just last week, the Round Fire wasn’t the only abnormally early burn to hit the West. A spate of wildfires broke out in northern Utah Feb. 8 and 9, burning a few hundred acres.
These early season fires owe much to the ongoing drought. The area burned by the Round Fire is usually covered in snow at this time of year, but [local photographer Jim] Stimson said the ground is bare. California’s paltry snowpack, dry soils and unseasonably warm temperatures make it easier for a spark, whether caused by humans or lightning, to catch and travel faster and farther than usual. While it’s nearly impossible to pin any particular fire event to climate change, we do know that the changing climate exacerbates the drought, which leads to more fires. Scientists say that Westerners can almost certainly expect more early-season fires like the Round, as climate change continues…
“The scary thing is future climate change may … dry out peatlands. If peatlands become more vulnerable to fire worldwide, this will exacerbate climate change in an unending loop.” Guido R. van der Werf
Six researchers have written a paper about how climate change is expected to increase the number of peat fires worldwide. This is disturbing for a number of reasons, including the health effects of the additional smoke that humans must breathe, and the additional carbon in the atmosphere may “exacerbate climate change in an unending loop.”
The researchers — Merritt R. Turetsky, Brian Benscoter, Susan Page, Guillermo Rein, Guido R. van der Werf, and Adam Watts — all work for universities. Even though the funding was supplied by five government agencies, if you want to read their paper at Nature Geoscience it will cost you between $5 and $32. Open Access is apparently not a priority for the universities and government agencies that are responsible for this important taxpayer funded research. The agencies that funded the research, other than the universities that employ the scientists, are National Science Foundation (NSF), NASA, The European Research Council, the Natural Sciences and Engineering Research Council of Canada, and the Desert Research Institute’s Division of Atmospheric Sciences (the environmental research arm of the Nevada System of Higher Education).
Government agencies should not fund research unless there is a guarantee that the results will be immediately, freely, and easily available on the internet.
Below is an article about their findings, supplied by the Desert Research Institute, the environmental research arm of the Nevada System of Higher Education, the employer of Mr. Watts.
The natural disaster plays out like a movie script – ash falling from the sky, thick smoke shutting down airports and businesses across the globe, and uncontrollable fires burning for days and weeks. But this is not from a script; rather, it is a vivid description of a future climate change scenario in which the Earth’s peat-rich regions become more susceptible to drying and burning.
New research published this week in the journal Nature Geoscience, co-authored by Adam Watts, a fire ecologist at Nevada’s Desert Research Institute (DRI) and deputy director of DRI’s Climate, Ecosystems, Fire and Applications Program, outlines the threat of drying peatlands (also known as mires) across the globe and their increased vulnerability to fire and carbon loss.
Peatlands – which make up around three-percent of the Earth’s land surface and store approximately 25-percent of the world’s soil carbon – are deposits of plant material and organic matter mixed with soil that is too wet to support high levels of decomposition. Peatlands are found on all seven continents.
Already the largest fires on Earth in terms of their carbon footprint, these smoldering fires burn through thick layers of peat, built up over thousands of years, which blanket the ground in ecosystems ranging from the tropics to the arctic.
“When people picture a forest fire, they probably think of flames licking up into tree tops, and animals trying to escape,” said the study’s lead author Merritt Turetsky, a professor of Integrative Biology at University of Guelph in Ontario, Canada. “But peat fires tend to be creeping ground fires. They can burn for days and weeks, even under relatively wet conditions. They lack the drama of flames, but they produce a lot of smoke.”
That smoke contains large amounts of carbon and makes peat fires dangerous to human health. It can worsen air quality and even trigger asthma and other respiratory problems.
“In addition to the amount of carbon released, the types of emissions also can make smoldering fires of greater concern than fires where most of the combustion takes place in flames,” said Watts, who is studying the emissions from burning peat and many other types of organic fuels with his DRI colleagues to determine their potential effects in the atmosphere and on our global climate.
“Peat fires are an example of wildfires having effects far beyond the areas where they occur, and these effects can last for a very long time,” he added.
Turetsky and former University of Guelph post-doctoral researcher Brian Benscoter teamed up with temperate and tropical fire scientists to summarize what is known about peat fires, from massive lightning-ignited fires that burn large areas of the boreal region to tropical fires often triggered by human activity.
“The tropical peatlands in Southeast Asia are a clear demonstration of how human activity can alter the natural relationships between ecosystems and fire,” explained Susan Page, a University of Leicester professor and co-author on the study. “Tropical peatlands are highly resistant to natural fires, but in recent decades, humans have drained peatlands for plantation agriculture. People cause the deep layers of peat to dry out, and also greatly increase the number of fire ignitions. It’s a double threat.”
This causes a host of problems, including health issues, airport and school closures, and political tensions.
The paper concludes that almost all peat-rich regions will become more susceptible to drying and burning with a changing climate. The authors also note that the ecology of peat fires and the role of peat fires in long-term Earth system processes need to be explored more thoroughly in future research.
“Thanks to satellite data, we are fully aware of the vast scale of burning in drained peatlands, mostly in Indonesia,” said co-author Guido van der Werf, a professor at Amsterdam’s VU University. “The scary thing,” Werf added,” is future climate change may actually do the same thing: dry out peatlands. If peatlands become more vulnerable to fire worldwide, this will exacerbate climate change in an unending loop.”
This research was supported by the National Science Foundation (NSF), NASA, The European Research Council, the Natural Sciences and Engineering Research Council of Canada, and the Desert Research Institute’s Division of Atmospheric Sciences.