Arctic wetlands are known emitters of the strong greenhouse gas methane. Well-drained soils, on the other hand, remove methane from the atmosphere. In the Arctic and boreal biomes, well-drained upland soils cover more than 80% of the land area, but their potential importance for drawing methane from the atmosphere—the underlying mechanisms, environmental controls and even the magnitude of methane uptake—have not been well understood.
A recent study led by researchers from the University of Eastern Finland and University of Montreal, in collaboration with Woodwell Climate Research Scientist, Dr. Anna Virkkala, has expanded our understanding of these dynamics, finding that Arctic soil methane uptake may be larger than previously thought. The results show uptake increasing under dry conditions and with availability of a type of soil organic carbon that can be used in microbial uptake processes.
The study was primarily conducted at Trail Valley Creek, a tundra site in the Western Canadian Arctic. The authors used a unique experimental set-up consisting of 18 automated chambers for continuous measurements of methane fluxes. No other automated chamber system exists this far North in the Canadian Arctic, and only few exist above the Arctic circle globally, most of which are installed at methane-emitting sites.
The high-resolution measurements of methane uptake (more than 40,000 flux measurements) revealed previously unknown daily and seasonal dynamics: while methane uptake in early and peak summer was largest during the afternoons, coinciding with maximum soil temperature, uptake during late summer peaked during the night. The study shows that the strongest methane uptake coincided with peaks of ecosystem carbon dioxide respiration—meaning that as methane is removed from the atmosphere, carbon dioxide production in the soil is high. Complementing flux measurements at Trail Valley Creek with measurements at other sites spread across the Canadian and Finnish Arctic showed that the availability of soil organic carbon and other nutrients may promote methane consumption in Arctic soils.
“The methane cycle has previously been primarily studied in wetlands because of their high methane emissions, but this study shows that drier ecosystems are also very important in the methane cycle,” says Dr. Virkkala.
These findings are highly relevant for estimating the current Arctic carbon budget, and for predicting the future response of Arctic soil methane uptake to a changing climate. According to the study, high-latitude warming itself, occurring up to four times faster in the Arctic than the rest of the world, will promote atmospheric methane uptake to a lesser extent than the associated large-scale drying.
“The Arctic methane budget has remained highly uncertain,” remarks the paper’s lead author, Dr. Carolina Voigt. “Our research provides one potential mechanism that might explain those uncertainties, and highlights the importance of methane measurements in drier ecosystems to calculate more accurate methane budgets.”
Located in Eastern Alaska, the Yukon Flats National Wildlife Refuge is larger than many U.S. states. It’s a roadless landscape of rocky mountain outcroppings, flat meadows, treeless tundra, and dense spruce forests, bisected by the Yukon River and dotted with thousands of lakes and wetlands. Several Alaska Native communities call the refuge home and subsist off of its natural resources. This diverse, expansive wilderness is well adapted to fire, and it’s not uncommon to see pink fireweed blooms or young grass and seedlings sprouting from burn scars.
But the relationship between fire and land here—as in many places—has been changing as the climate warms. Yukon Flats sits atop ancient, ice-rich ground, called Yedoma permafrost, formed during the last ice age. Thawing Yedoma is a significant source of carbon dioxide and methane emissions to the atmosphere. Fire, made more intense and frequent by climate change, threatens to accelerate that thaw. In an effort to preserve carbon stores, the U.S. Fish and Wildlife Service recently dedicated 1.6 million acres of the Yukon Flats refuge to piloting a new firefighting regime, one designed to protect carbon, in addition to human lives and property.
This decision was, in part, influenced by research led by Dr. Carly Phillips, during her time as a research scientist at the Union of Concerned Scientists, alongside Woodwell Climate Senior Science Policy Advisor, Dr. Peter Frumhoff, and Associate Scientist, Dr. Brendan Rogers. In a 2022 paper in Science Advances, the group quantified the threat boreal forest fires pose to climate goals. Wildfires in boreal North America alone could, by mid-century, use up 3% of remaining global carbon dioxide emissions associated with keeping temperatures below the Paris Agreement’s 1.5°C limit. This is a conservative estimate—the authors suggest the true numbers could be even larger as the accelerating effect of fires on permafrost thaw, and the release of other greenhouse gasses, were not included in the analysis.
The study also examined the cost-effectiveness of combatting those fires as a potential climate solution. Molly Elder, an economics and public policy Ph.D. candidate at Tufts, performed an analysis of data from across Alaska’s fire management zones and found that actively suppressing boreal fires could cost less than 13 dollars per ton of carbon dioxide emissions avoided—putting it on par with other carbon mitigation solutions like onshore wind or utility-scale solar.
“The work we did in this project proved and quantified what the management community already knew, which is that management is effective at reducing burned area when fires are actively suppressed,” says Elder.
Combating boreal fires could provide much needed mitigation, and at a low cost, but there are some logistical obstacles between the hypothetical model and actual implementation. Typically, in Alaska, boreal forest fires are left to burn unless they present a risk to human life or property. This is partly because these forests are fire-adapted, but also partly due to the sheer vastness of boreal wilderness. With limited resources, it is not always practical or possible to track down and put out a fire, especially in a place without roads like Yukon Flats. Firefighters are already stretched thin with lengthening and increasingly high-intensity fire seasons.
So the research group worked with the fire management community in Alaska, facilitated by the Alaska Fire Science Consortium, to better understand the needs of firefighters and demonstrate the co-benefits of fire suppression in addition to preserving carbon.
“Many of the fire managers expressed how stretched their resources already were and resistance to the idea that yet another mandate would be added to their plate,” says Dr. Phillips. “However, after discussing the implications of our research, and the ambition that additional funding would come with any mandate, we got more buy-in.”
The other concern managers raised was whether fire suppression would ultimately be successful in achieving their goals. Historically, fire suppression efforts in the US have been counterproductive to protecting forests.
In the late 1800s, lack of understanding of the ways Indigenous communities in Western states have used fire to maintain healthy forests resulted in decades of near-total suppression of fire in the region. In many western US forests, (adapted to what Dr. Rogers calls “high-frequency, low-intensity” fire) suppression allowed highly flammable, dry vegetation—which would normally be periodically burned away—to build up. When fires did spark, they were then capable of growing to a size and intensity that could damage, rather than activate, the forest.
But in boreal Alaska and Canada, it’s just the opposite. The spruce-dominated forests are adapted to high-intensity fires that only return every hundred or so years. As climate change speeds up the return of fires with hotter and drier conditions, boreal forests have begun to suffer major losses.
“The frequency of boreal fires, ultimately, is increasing. In many places we’re seeing more reburning and larger burned areas,” says Dr. Rogers. “Climate change and human actions are shifting that fire regime out of its historical range into this new realm. So the whole idea of fire suppression in the boreal is to keep fires closer to historical levels, to which the systems and fauna are adapted. Suppression can help delay permafrost degradation, limiting carbon emissions and buying us time to reach our climate targets.”
Past missteps with fire suppression have made fire managers cautious, though. Lisa Saperstein, Regional Fire Ecologist with U.S. Fish and Wildlife, notes that, with limited resources, priorities in intense fire seasons will have to shift to protecting human settlements over carbon and permafrost. But, given the co-benefits of keeping fire activity to historic levels—and the urgency of reigning in emissions in any way we can—managers in Yukon Flats were willing to try.
“This type of shift in values is always difficult, especially when the outcome is uncertain. Support from leaders of fire management organizations, in addition to land managers, has been a key factor in this effort moving forward,” says Saperstein.
This change in tactics won’t mean that every fire that ignites will be put out—both impractical and unhelpful from an ecological perspective—but it will mean more aggressively targeting fires when they arise. Since the 1980s, when fire was detected in Yukon Flats, it would be monitored by the Alaska Fire Service, but not suppressed, except when presenting a threat to human communities.
“This pilot project is a new twist to a long-standing partnership between the U.S. Fish and Wildlife Service and Alaska Fire Service. For select areas of the Refuge, now if a fire start is detected, we ask the Alaska Fire Service to only send a crew if they are confident in 100% containment within three days,” says Yukon Flats Refuge Manager, Jimmy Fox.
The suppression teams will target fires that they judge as “quick fixes”, curbing the potential for them to grow into large, stand-replacing sized blazes. If a fire becomes too big to fight quickly, the teams revert to the old tactic of simply monitoring.
“If a crew is deployed, we ask that they cease suppression and return to base after three days, regardless of containment status,” says Fox. “This request is grounded in concern for the Alaska Fire Service having resources available if communities become threatened from other fires.”
Fox says refuge management and Alaska Fire Service members will stay flexible as the pilot project unfolds so they can respond to changing conditions.
“In conservation, we tend to focus on the technical aspects of a challenge and avoid the difficulties that come with asking ourselves to adapt,” says Fox. “This pilot project is both adaptive and technical. It has required me to stay curious and listen. It has required me to learn new information, and share it in a way that is comprehensible. It’s required being comfortable with uncertainty, and yet standing in purpose. It has been a learning journey so far, and will continue to be.”
On the research side, the team at Woodwell Climate hopes this new strategy will present an opportunity to study the practical implementation of fire suppression as a climate solution.
“This is the proof of concept,” says Dr. Frumhoff. “This is the opportunity to really see in a rigorous way whether we can apply this solution at a meaningful scale and gain meaningful carbon benefits with relatively modest cost. And it’s directly traceable to the conversations that the research team had with fire managers.”
The 1.6 million acres slated for fire suppression are small compared to the 8.6 million that comprise the entire refuge, or the 5.6 billion acres of permafrost in the northern hemisphere, but it’s a very important start. Research and analysis of the effectiveness of this solution could aid its expansion to other regions of the Arctic.
“It’s a big moment, because, while it’s obviously a relatively small area compared to all of Alaska, 1.6 million acres is still a lot of land,” says Dr. Rogers. “We’re hoping that it’s a jumping off point and can translate to other refuges and other agencies with the addition of proper funding and staffing.”
And each summer, the case for protecting permafrost and boreal carbon, while working to dramatically reduce emissions from fossil fuels, continues to grow.
“Every year that goes by, as fires intensify and climate change gets worse, this message might resonate just a little more, ” says Dr. Rogers. “Because it’s a problem that’s not going away if we do nothing about it. And we can do something about it.”
It’s a big idea—a pan-Arctic monitoring network for permafrost emissions—but big ideas are exactly what The Audacious Project was created to foster.
This April, Woodwell Climate Research Center was awarded 41.2 million dollars through Audacious to not only build such a network, filling gaps in our understanding of how much carbon is released into the atmosphere from thawing permafrost, but also to put research to work shaping policy and helping people.
The new project, called Permafrost Pathways, combines scientific prowess from Woodwell with policy, community engagement, and Indigenous knowledge from the Arctic Initiative at Harvard Kennedy School’s Belfer Center for Science and International Affairs, the Alaska Institute for Justice (AIJ), and the Alaska Native Science Commission.
Carbon emissions from permafrost thaw are one of the biggest areas of uncertainty in global climate calculations. Thawing permafrost is expected to release between 30 and 150 billion tons of carbon by 2100, the higher estimates on par with or even exceeding the United States’ cumulative emissions if allowed to continue at current rates. Yet permafrost is not accounted for in carbon budgets and international agreements. Permafrost Pathways will develop more complete data on permafrost carbon and deliver that research into the hands of those poised to decide how we deal with the warming Arctic.
Permafrost Pathways is led on the Woodwell side by Arctic Program Director Dr. Sue Natali and Associate Scientist Dr. Brendan Rogers, who have both been researching permafrost carbon for years. Dr. Natali found her way to the Arctic through a desire to work in a place significant to the global carbon story. The rapid changes she has witnessed in the past decade have underscored the Arctic as ground zero for climate change.
“I’ve seen dramatic changes from one year to the next in the places where I work, and Arctic residents have been observing these changes for decades,” Dr. Natali says. “You can measure something one year and then the ground there collapses the next. The physical changes across the landscape are really startling to see.”
Drs. Natali and Rogers have seen eroded hillslopes, research trips abandoned due to wildfire, community meetings with Arctic residents whose homes are sinking—every experience reinforced the fact that there was still much more to learn about how thawing permafrost feeds into climate change and is impacting Arctic communities.
The Audacious grant will allow Drs. Natali and Rogers to pull together the threads of their prior research into a project that starts to tackle the issue on a grander scale.
“When you’re focused on individual problems or hypotheses, you’re not able to really think big about something like monitoring across the Arctic,” says Dr. Rogers. “Opening up a funding source like this lets you think at a scale that matches the problems we face.”
The project is thinking really big, with the goal of installing 10 new eddy covariance towers—structures with instruments that measure carbon flux—in key areas where data is currently lacking. Pathways will also maintain existing key towers that would otherwise be decommissioned, and augment others to measure carbon fluxes year-round.
“There are a lot of existing towers that are either not running through the winter, or they’re not measuring methane, or they’re on hold for instrumentation upgrades or lack of funding,” Dr. Natali says. “We will get even more new data by maintaining old towers than constructing new ones.”
In parallel, Woodwell will work with a team at University of Alaska Fairbanks to develop a novel permafrost model that fully harnesses the data, accounting for important but currently neglected processes, and ultimately delivers more accurate projections of permafrost emissions to inform policy makers and Arctic communities.
While the science team ramps up new data collection, AIJ will be breaking down the issue of adaptation. The Arctic is warming faster than anywhere else on Earth, and it is not waiting for exact measurements to make the consequences known.
The land upon which many Alaska Native communities are located is destabilizing in the face of usteq—a Yupik word for the catastrophic ground collapse that occurs when thawing permafrost, erosion, and flooding combine to pull the ground out from under them. In many places the formerly solid cornerstones of villages—houses, roads, airports, cemeteries— have had to be picked up and moved to more stable ground.
“It is an awful, awful decision that communities are being faced with because the land on which they’re living is becoming uninhabitable,” says Executive Director of AIJ, Dr. Robin Bronen.
On top of the trauma of watching their villages sink into the Earth, there is no clear path for Arctic communities deciding they must completely relocate.
“It’s become painfully clear that we in the United States have no institutional or governance structure to facilitate this type of movement of people,” says Dr. Bronen. There is no standardized way for people displaced by the climate crisis seeking resettlement to apply for funding and technical assistance for a community-wide relocation.
“If policy changes aren’t made nationally, then a lot of communities in the United States are going to be experiencing this incredible disconnect between making the decision that they are ready to leave, but having no resources to implement that decision,” says Dr. Bronen.
Permafrost Pathways will be working with Arctic residents to help them adapt to their rapidly shifting landscape. Through AIJ and the Alaska Native Science Commission, the project will connect with communities, collaborate to generate data they can use in their decision making and, if they make the choice to move, work with them to secure the resources needed for relocation.
Permafrost Pathways isn’t the first to tackle these issues but, Dr. Natali says, it does represent a unique combination of expertise that could push forward both carbon mitigation and climate adaptation policies.
Leader of the Arctic Initiative, professor, and Senior Advisor to Woodwell’s president, Dr. John Holdren understands the value of connections in making lasting change; he has been speaking to top policy makers in the U.S. and abroad for much of his career.
“All of us at the Belfer Center have been linking science and policy for a long time and communication is important to that,” says Dr. Holdren. “In my view, it’s going to remain important to have personal connections at high levels.”
Working through these connections, Permafrost Pathways will put the project’s science into the hands of policymakers to impress upon them the issue’s urgency.
“All the news coming out about permafrost carbon has been bad news,” says Dr. Holdren. “I think what we are going to find is that the high estimates are much more likely to be right than the low estimates. We’ve got to get that factored into the policy process.”
For Dr. Natali, the most important outcome of Permafrost Pathways is a future in which the threats presented by permafrost thaw are taken seriously by governments.
“I want to see permafrost thaw emissions accounted for,” says Dr. Natali. “I want to see the national and international community actually wrestle with the effects of permafrost thaw and to take action to respond to the climate hazards.”
Dr. Rogers says he hopes the collaborative nature of this already-big project will have even larger, rippling effects— paving the way for new partnerships and policy change.
“There’s the critical work that we will be doing, and then there are the new doors that a project of this scope opens,” says Dr. Rogers. “And we aren’t reaching our end goal without those open doors.”
The Audacious Project is an initiative of the non-profit TED that funds large-scale solutions to the world’s most challenging problems. Every year, the Project selects a cohort of big ideas to nurture with funding and resources.