In 2023, Canada experienced its worst wildfire season to date. Fires raged across all 13 provinces and territories, breaking national records for burned area and carbon emissions.

Fires have a complex impact on both the global and regional climate. While fires contribute to warming through the release of stored carbon from trees and soil, they also create an unexpected cooling effect. Postfire changes to vegetation composition and coverage have an impact on albedo—the amount of sunlight reflected by a surface. The absence of the tree canopy no longer conceals snow, thus reflecting more incoming solar radiation which can cool the local environment.

“If you have a more reflective surface, like ice or snow in particular, it’s going to reflect more of that sunlight back to space, and so it’s going to have a cooling effect compared to if it wasn’t there,” says Rogers. “Because if it wasn’t there, then the darker land or the ocean would have absorbed more of it and heated.”

These changes in albedo have historically partially offset the warming caused by fire-induced emissions; however, climate change is disrupting this balancing effect.

In a newly published paper, co-authored by Woodwell Climate Senior Scientist Dr. Brendan Rogers, researchers found a 29% decrease of the regional climate-cooling impact of boreal wildfires since the 1960s. This represents one aspect of a critical shift in past ecosystem dynamics—not only is climate change responsible for rising global temperatures, but it is also weakening the natural mechanisms that once regulated this rise.

“The consequences of retreating snow cover become especially clear at the scale of individual fires,” says Max van Gerrevink, lead author of the study and postdoctoral researcher at Wageningen University and Research. “Historically, nearly half of all Canadian wildfires reached a natural climatic break-even point, where snow-driven surface cooling fully offset the warming caused by fire-related emissions. Today, that proportion has fallen dramatically, to only about one in four or five fires.”

The study used remote sensing to map the predicted changes in surface albedo over a 70-year postfire period assuming carbon dioxide emissions maintain current levels until 2050, then decrease, eventually reaching net zero by 2100. For Canada’s boreal forests, this means earlier snow disappearance rates, later snow onset and warming temperatures—all of which impact albedo.

When considered alongside a previous study co-authored by Rogers, the decreasing power of the cooling effect is projected to continue even further.

“Compared to pre-climate change, we’re talking about, over the next several decades… a 50% to 60% reduction due to earlier snowmelt,” says Rogers. “It’s important to be aware of this when you’re thinking about ‘What does this mean for the earth system,’ and ‘How might you manage these fires.’”

The implications of this finding are of growing concern, as warmer and drier weather conditions associated with continued climate change are subjecting Canada’s boreal forests to more severe and longer fire seasons. During the 2023 Canadian fire season, an estimated 647 teragrams of carbon were released—a number comparable to the annual fossil fuel emissions of the largest-emitting nations and only exceeded by India, China and the United States.

With more carbon being released annually from worsening fire seasons and a diminishing climate-cooling effect, Canada’s boreal ecosystems are facing an amplified threat from exacerbated warming. As the study found, the subsequent weakening of the climate-cooling impact implies that contemporary boreal fires are, on average, twice as likely to result in a net climate-warming influence.

“Fires both warm through greenhouse gas emissions and cool through changes to land surface albedo,” says Rogers. “The cooling impact is declining, but the carbon impact is not, and it might even be growing because we’re seeing more permafrost emissions after wildfires.”

Rogers stressed the importance of considering albedo and carbon as two parts of a larger equation rather than two factors that act in opposition. This is due to the fact that albedo’s impact is limited to the geographic area where these fluctuations occur and therefore is not as widespread. Furthermore, he emphasized the need for measures that directly target carbon emissions in order to comprehensively address climate change.

“The reality is the spatial footprint from the albedo changes in Canada have very little impact on us down here in the lower 48 or other parts of the globe,” says Rogers. “And I think that’s important, because the carbon impacts are global and do impact us and everyone else on the planet.”

Grazing lands are everywhere. These lands, used to raise domesticated animals like cows and sheep, span over 12 billion acres, comprising nearly 40% of ice-free land on Earth, and represent the largest category of human land use.

Grazing lands are not just working lands, they are also critical grassland, shrubland, and woodland ecosystems that provide important ecological benefits like carbon storage. Poor management practices like overgrazing have resulted in the degradation of these ecosystems. In the United States, over half of rangelands are considered degraded, resulting in the loss of 50 billion tons of carbon that would otherwise be stored in soils. Grassland species are in decline, and the productivity of these lands has dropped, with economic consequences for ranchers.

What is regenerative grazing?

Regenerative grazing is the practice of moving livestock between pastures to allow more time for vegetation to rest and re-grow, and it is often touted as an antidote to degradation. The technique is intended to emulate the movements of wild grazers like bison and elk and can maximize grass growth and help incorporate more plant biomass into the soil, two factors that are key to increasing soil carbon. Regenerative practices can also improve the quality and diversity of food for grazing animals.

Because of its potential, regenerative grazing practices have generated much buzz, particularly in the world of carbon credits. Current proposed grassland management projects on the Verra Registry —the world’s largest public database on carbon credits — estimate that in total they will remove as much as 40 million tons of CO2 per year. Despite these claims, there have been few conclusive scientific studies to verify. Accurate soil carbon estimates are crucial to right-size expectations for producers, policymakers, and financial markets supporting regenerative grazing practices as a potential climate solution, yet this lack of conclusive evidence leads to the need for more rigorous analysis.

Why is it so hard to study rangeland carbon?

An ideal study of the carbon storage potential of regenerative practices requires before and after measurements on comparable fields using both conventional and regenerative techniques. This is hard to do for a couple of reasons.

First, rangelands are complex systems with many different factors, including soil type, vegetation and land use history, playing into how much carbon gets locked away in soils. Second, the grazing practice changes are individually tailored to work with each ranchers’ operation, adding complexity. Third, expected changes in soil carbon are small relative to the large and variable background carbon stocks in rangelands, often leaving scientists looking for a needle in a haystack.

A review assessing the quality of existing evidence, led by Woodwell Climate researchers, found 70 papers that attempted to answer this question. Of those 70 papers, only 10 were found to make scientifically robust comparisons of soil carbon between conventionally and regeneratively managed sites. These 10 studies showed an average result of no change in carbon. Most of these 10 studies used small experimental plots that allow researchers to control for confounding effects, but can simplify the system past the point of recognition for a rancher. Two studies even used lawn mowers instead of grazing animals, raising questions about the applicability of these findings to real, working ranches.

A large subset of the 70 studies compared soil carbon levels at ranches already under regenerative management with nearby conventionally grazed ranches. These studies suggest that on average regenerative grazing can sequester 0.7 tons of CO2 per acre per year more than conventional grazing. However, this approach makes the assumption that the present-day soil carbon level on a conventionally grazed site is equivalent to the baseline level of the regenerative site prior to change. This assumption requires careful pairing of vegetation, soil type, climate and land-use history that was not documented in most of the studies.

The variable quality of existing studies leaves us no closer to understanding the benefits of regenerative grazing, and scientific study is still needed.

Woodwell’s rangeland carbon projects are working to fill the data gap

The flurry of attention on regenerative management practices means funding and executing long-term studies that can generate high-quality data is an urgent priority. Projects on the Verra Registry are claiming to sequester more than twice as much carbon as the Woodwell analysis was able to estimate based on existing data. Left unverified, this could result in greenwashing ranching operations and carbon credit programs.

Woodwell researchers are actively exploring ways to fill this knowledge gap. Soil spectroscopy, a method that measures the interaction between light beams and soil particles to determine their chemical composition, offers a lower cost option for analyzing a large amount of soil samples to determine carbon content. Easier and cheaper soil analysis options will facilitate future research into the benefits of various land management practices, with applications for farms, ranches and other landscapes.

Woodwell scientists have also developed RangeSTAR, a system for tracking changes in plant productivity and soil carbon at a land management scale with a high level of detail. RangeSTAR combines computer simulations with remote-sensing data and field measurements of rangeland-health indicators. As the project progresses, researchers hope to get a clearer picture of the role rangelands can play in combating the climate crisis.

A message from President & CEO Dr. Max Holmes

My house was built in 1870. It has been heated by wood, coal, oil, natural gas, and now electricity drawn from the sun. In one sense, that is a mundane property record. In another, it is the entire history of human energy, compressed into a single address.

Wood came first. It always does. Since our ancestors learned to control fire, biomass has been the default answer to cold and darkness. The house would have had a cast-iron stove, fed by wood cut from nearby forests. This is how virtually every human being on earth stayed warm for tens of thousands of years, and many still do. It worked, but it was labor-intensive, land-hungry, and contributed to deforestation.

Coal replaced wood in the industrializing Northeast not because it was loved but because it was dense, cheap, and abundant. A ton of coal contained far more energy than the equivalent volume of wood and could supply cities that had long since stripped their surrounding forests. Then came oil – heating oil delivered by truck, burned in a furnace that could be thermostatically controlled. Oil heat was modern. It was convenient. It was what the house was running on when my wife and I bought it in 2000. The following year, we switched to natural gas, piped directly to the boiler—cleaner than oil, cheaper at the time, and widely regarded as a “transition fuel.” Last year, we made what I believe will be the final transition: heat pumps, powered by electricity, with solar panels on the roof and a contract for renewable energy for anything we draw from the grid.

The sequence—biomass, coal, oil, gas, electricity—is not just our home’s story. It is the arc of modern civilization. And the direction of travel has always been the same: toward fuels that are denser, cleaner, and more controllable, and away from those that are dirtier, heavier, and harder to move. Electricity, especially when generated from wind and sun, is the logical end of that arc. The sun and wind are limitless natural resources and our ability to harness them into electricity will only continue to be more efficient. The energy transition the world is now debating is not some radical rupture; it is the next step in a journey that has been underway since the first furnace replaced the first wood-fired stove.

The only real question is speed. And here, the conflict now consuming the Persian Gulf offers an unexpected answer. The closure of the Strait of Hormuz following the outbreak of military conflict with Iran has removed close to one-fifth of global oil supplies from the market. Prices have reached $100 per barrel or higher. Nations that import the majority of their fuel from the Persian Gulf are facing genuine shortages. The head of the International Energy Agency has called it the greatest global energy security challenge in history.

The conventional assumption might be that an oil shock slows the energy transition – that higher prices make everything more expensive and governments retreat to fossil fuels out of desperation. History suggests the opposite. The 1973 Arab oil embargo helped to launch solar research, energy efficiency standards, and nuclear expansion. Countries around the world are again confronting the danger of energy dependence. That recognition tends to produce investment in alternatives, not capitulation to the status quo.

There are headwinds, of course. The current U.S. administration has been openly hostile to renewable energy, rolling back incentives and attempting to prop up coal and oil production. But administrations are temporary. Solar panels and heat pumps are not. The economics of clean energy have already crossed the threshold at which policy resistance can reverse them; what governments can do now is slow the transition at the margin, not stop it. And a geopolitical crisis that makes the cost of fossil-fuel dependence unmistakable—not in future climate projections but in today’s energy prices—has a way of clarifying minds.

My house has been through this before. It didn’t choose its fuels for ideological reasons; it followed the logic of cost, availability, and technology. The world’s energy system will do the same.

At a time when climate victories are scarce, an acceleration of the energy transition is reason for hope. Those with the financial means—and perhaps the broader good fortune to live in a time and place where the choice is available—can lean into this transition, doing what they can to speed the inevitable shift away from fossil fuels and toward what I believe will be humanity’s ultimate energy source: clean electricity generated from renewable sources.

The energy transition alone will not solve the climate crisis, but it is an essential step in that direction.

Onward.

Max signature

How climate change is influencing Europe’s record-breaking heat wave

a sunset in an orange sky over a dark skyline

NPR’s Michel Martin speaks with Jennifer Francis, senior scientist at the Massachusetts-based Woodwell Climate Research Center, about the impact of Europe’s heat wave and its links to climate change.

Read more or listen on NPR.

Since the 1970s, categorical exclusions (CEs) within the National Environmental Policy Act have applied only to activities that have been consistently and scientifically reported to not have a significant effect on the environment. The thinning of forest and woodland density of areas up to 5,000 acres, a significant increase from the current 70 acre limit, would undoubtedly have a significant impact on the environment, as demonstrated by the large repertoire of scientific research highlighting the critical role of forests in storing atmospheric carbon. Furthermore, the forest ecosystem has become increasingly vulnerable to wildfire due to human activity and climate change. Wildfires present extreme threats to human health, with over 15,000 deaths being attributed to wildfire particulate matter over the last 15 years. Even without any major escalation in the deterioration of our forests, the scale and impact of wildfire smoke on human health is projected to increase.

Altered fire regimes based on the principles of wildfire suppression, which this proposed revision uses in its justification, do not recognize the natural benefit of fire and have been shown to exacerbate fire-associated emissions. With such a critical issue at hand, the consultation of scientists and local communities is imperative, which is not reflected in this proposal. Thus, Woodwell strongly opposes the broadening of this CE for the Bureau of Land Management.

Scientific Objection to the Categorical Exclusion for Forest and Woodland Density Management

The proposed revision of this CE is based on the strategy of mechanical thinning. However, there is little to no scientific evidence concluding that the act of mechanical thinning alone universally lessens the risk of wildfire, as integrated fire management strategies are extremely dependent on the context of the ecosystem in which it is deployed. Woodwell research has found that without tailoring the wildfire strategies to their specific environment and pairing it with other more traditional wildfire management methods, these actions may have adverse consequences.

Under conditions of increased temperatures, which would be further amplified by increased carbon emissions driven by deforestation, burned area is expected to increase. With the incredible danger that wildfires pose to human safety, any actions that may degrade natural ecosystems and amplify wildfire impacts must be coupled with extensive environmental review, not the absence of such. By foregoing environmental review through the expansion of this CE, the Federal government is inviting the potential to further endanger our forest ecosystems and the lives of Americans.

The Critical Role of Forests in Carbon Sequestration

The proposed rule fails to recognize the integral role that forests play in carbon sequestration. BLM forests contain about 8 million acres of old growth and 13 million acres of mature forest – about ⅔ of the total area of BLM forest. Mature and old-growth forests, with their much older and larger trees, hold more carbon. Mature and old-growth forests are also more resilient and adaptive in the face of disturbances such as wildfires, which makes them a high priority for environmental protection. It is hard to imagine that these carbon-dense ecosystems would be excluded from logging under the proposed CE.

Woodwell researchers have also found that even beyond the cooling effects of sequestered carbon, forests provide biophysical cooling effects on a local and global scale. This unique quality promotes local climate stability, reducing extreme temperatures year round.

Since 2001, forest fire carbon emissions have increased by 60%. It is projected that by mid-century, wildfires in the northern region of North America would alone contribute to a cumulative net source of nearly 12 gigatonnes of carbon dioxide emissions into our atmosphere, further exacerbating temperatures and subsequent wildfire ignitions.

Impacts on Climate Resilience and Risk Mitigation

While the proposal argues that expanding forest thinning will reduce wildfires, scientific research has frequently called on officials to implement natural climate solutions to increase ecosystem resilience and limit climatic threats such as wildfire.

Fire is a natural and integrally important process in the life cycle of our forest ecosystems. Woodwell scientists study and promote traditional methods of fire management of local and indigenous peoples who recognize the environmental benefits of fire via prescribed burns. Trained professionals can employ these tactics of prescribed or controlled burns to reduce the build up of natural fuels, benefiting plants and wildlife by recycling the carbon back to the earth.

Conversely, we have found that more modern fire suppression tactics have led to oversuppression, contributing to the buildup of dry fuel on the forest floor. Combined with the ever warming temperatures destabilizing atmospheric conditions, increasingly frequent lightning strikes ignite these more flammable forests.
regular fires to periodically clear out this fuel, the land has become more vulnerable to intense and widespread fires. Woodwell is especially concerned with the proposed expansion of the CE of forest and woodland density as it relies on the tactic of mechanical thinning and strives for wildfire suppression, thus risking increased rates of wildfire. In order to properly manage fires in a way that creates a healthier and safer environment, fire management must utilize fire itself.

The proposed revision’s emphasis on mechanical thinning and logging also raises concerns regarding human impact. Anthropogenic influences such as population density, a human footprint index, and roadless volume all have significant statistical correlations to fire occurrence. Previous actions, such as the rescission of the 2001 Roadless Rule, have already demonstrated the harm that logging and other commercial activities pose to forests. Recent research has shown that roads increase the likelihood of wildfire ignitions because human activities are the most common cause of wildfire; once an area becomes accessible, the probability of wildfire increases. The massive expansion from 70 acres to 5,000 acres eligible for the CE of forest and woodland density would only incite more logging activities and the
acceleration of associated fire occurrence.

Lastly, this announcement fails to elaborate on the “additional tool” which it claims will assist decision-makers in planning areas to implement fuel treatments. Without a demonstrated and sound scientific basis for this tool, the likelihood that project decisions will reflect consideration of forest values beyond timber production is cast into doubt.

Conclusion
The proposed expansion of the Categorical Exclusion rejects scientific evidence and prioritizes logging activities over the safety of American citizens. Woodwell urges the Department of the Interior to:

Integrate the implementation of prescribed or controlled burns to lessen excess vegetation in wildfire mitigation, as opposed to suppressing fires and building flammable materials.
Engage and consult with local communities to create collaborative and tailored fire management strategies based on the particular ecosystem in which they will be deployed.
Provide details about the “additional tool” that will assist in designating fuel treatment areas, specifically its scientific basis and values.
Evaluate each project for the impact of estimated carbon emissions on the broader environment.
Maintain the CE of 70 acres for tree and woodland density so as to minimize forest disturbances and build ecosystem resilience to wildfire at minimum. Ideally, perform environmental assessments under NEPA for all projects regardless of size.

Woodwell Climate Research Center urges the Council on Environmental Quality to reconsider aspects of this Categorical Exclusion to ensure that the pursuit of efficiency does not compromise the scientific rigor and comprehensive scope necessary for effective environmental review under NEPA. Accelerating logging activities and forest deterioration via inappropriate thinning will only amplify the wildfire risk that this proposal claims to address. It is imperative that the Bureau of Land Management’s NEPA implementing procedures facilitate, rather than hinder, the full consideration of environmental impacts, cumulative effects, and health of our citizens.

In a new joint “Feeding Resilience” report, the Center for Climate and Security, an institute of the Council on Strategic Risks, along with the Woodwell Climate Research Center, shows that climate change is sharply increasing the risk of crop failures in global breadbaskets, which would pose serious threats to Europe, the NATO alliance, and global stability, at a moment of multiple geopolitical shocks. In India and Europe, for example, climate change in the next decade and a half is set to increase the chance of key crops failing by between two- and six-fold. This rising risk comes as the world is already facing severe food shocks due to the wars in Iran and Ukraine, and is entering into a potentially unprecedented El Niño season. The report offers a range of policy recommendations to address this major risk.

The report, Global Breadbaskets: Food System Resilience as a Strategic Imperative, draws on a range of global crop models to assess the growing risk of climate-driven agricultural failures in ”key producers of wheat, maize, and rice” like Europe and India, and examines the cascading geopolitical consequences of a world in which multiple breadbaskets fail at once.

The lead author on the report, Tom Ellison, Deputy Director of the Center for Climate and Security, stated: “We have plenty of examples of how crop failures can contribute to political instability, from the French Revolution to the Arab Spring. In today’s environment, global breadbasket failures could strain NATO priorities, prompt unrest in key countries, and upend trade relationships. Amid climate change, geopolitical uncertainty, food shocks from the war in Iran, and Russian hybrid warfare, investing in a resilient food system isn’t in competition with security–it’s a key part of it.”

Co-author of the report, Noah Fritzhand, Research Fellow at the Center for Climate and Security, added: “With the implementation of NATO’s updated baseline resilience requirements come July and adoption of the EU’s new integrated framework for climate resilience later in 2026, member countries have an opportunity to prioritize investments in resilient food systems, at home and abroad, that can both limit exposure to climate risks and meet Europe’s strategic goals.”

Dr. Alexandra Naegele, co-author of the report and Research Scientist at Woodwell Climate Research Center, noted: “Climate change doesn’t just threaten crop yields and grain quality—it destabilizes entire food systems, from labor and livestock to food storage and transport. These impacts are colliding with a powerful El Niño taking shape, which is expected to weaken the monsoon, trigger heatwaves, and reduce rainfall across India. Quantifying these climate-driven risks is an essential step toward building resilient food systems and safeguarding global food security.”

Co-author of the report, Monica Caparas, Research Scientist at Woodwell Climate Research Center, concluded: “The consequences of a breadbasket failure extend far beyond the region where it occurs. As globally important food-producing regions face growing risks of climate-driven disruption, the effects can ripple through livelihoods, supply chains, food assistance systems, and geopolitical relationships. Understanding and preparing for breadbasket failures is both a national security priority and a humanitarian imperative—one that can help protect lives, reduce instability, and strengthen food resilience before a regional shock becomes a wider crisis.”

Read the full report.