Climate scientists warn against burning biomass as clean energy solution / 02
Forests endure as a carbon sink despite regional pressures / 03
Here’s how climate change is affecting hurricane season / 04
Air quality monitoring to machine learning: Fund for Climate Solutions awards six new grants / 06
In the news: highlights / 07
Experts from Woodwell Climate Research Center urge IRS and Treasury Department to adopt more rigorous guardrails regarding the use of wood for bioenergy in the agencies’ proposed guidance on clean electricity tax credits
In recent public comment, scientists at Woodwell Climate Research Center warn against the use of the Inflation Reduction Act’s (IRA) clean electricity tax credits to support biomass as an effective clean energy solution. Scientists cited its higher carbon footprint per unit energy compared to burning fossil fuels, and highlighted that claims to offset these emissions by planting trees are misleading, as new trees take decades to centuries to recapture lost carbon. The comment, submitted in response to the Internal Revenue Service (IRS) and U.S. Department of Treasury’s proposed guidance on the Clean Electricity Production Credit and Clean Electricity Investment Credit, advocates for more rigorous guardrails from the agencies regarding the use of wood for bioenergy, greater regulatory clarity, and more accurate accounting of emissions from woodburned fuel.
The Clean Electricity Production and Investment Credits were designed to provide incentives “to any clean energy facility that achieves net zero greenhouse gas emissions.” The proposed guidance, released in June, is intended to clarify and add certainty around how to measure and define “net zero,” and how clean energy production facilities can qualify for these incentives.
In their comment, however, scientists emphasize more work must be done to achieve this goal: “The content of the proposed guidance is ambiguous or even conflicting about some parts of the rule regarding sources of forest bioenergy,” they write. “Parts of the guidance should be made much clearer and more definitive to ensure that there are no unintended consequences. Guardrails could be put in place to avoid the many ways
that increasing use of wood for bioenergy would increase emissions rather than having the desired effect of decreasing emissions. It is also important to consider the many values of forests beyond climate mitigation, such as timber, biodiversity, water, and recreation.”
Scientists also note the proposed guidance does not properly account for the net emissions associated with forest bioenergy— all of which contribute to its high carbon footprint and add to concerns from experts that biomass can actually worsen the climate crisis—including those from harvesting intact forests, logging debris, transporting woody biomass, and converting biomass to fuel, as well as from feedstock, fertilizers, and forest management practices like thinning, where live trees are removed to reduce wildfire risk or promote forest growth, and more.
Because many of these emissions are left out, the proposed guidance overestimates the potential of forest bioenergy to achieve the IRA’s intended goal of lowering emissions, and further fuels incorrect assumptions that biomass energy is an effective, carbon-neutral alternative to fossil fuels.
Throughout the comment, scientists offer recommendations to help decision makers more accurately incorporate and represent these emissions in policy. For example: 1) account for both direct and indirect emissions; 2) avoid the fallacy of assuming carbon neutrality; and 3) take a case-by-case approach to calculate the counterfactual emissions, or what the emissions would have been had the wood or biomass not been used for bioenergy; among others.
Maddie Rocklin Associate Vice President, 90 West
Despite facing regional threats like deforestation and wildfires, the world’s forests continue to be a powerful weapon in the fight against climate change. A new study reveals these vital ecosystems have consistently absorbed carbon dioxide for the past three decades, even as disruptions chip away at their capacity. The study, based on long-term ground measurements combined with remote sensing data, found that forests take up an average of 3.5 ± 0.4 billion metric tons of carbon per year, which is nearly half of the carbon dioxide emissions from burning fossil fuels between 1990 and 2019.
The study titled “The enduring world forest carbon sink,” published in the June issue of the journal Nature, highlights the critical role of forests in mitigating climate change. The study further shows that deforestation and disturbances like wildfires are threatening this vital carbon sink.
lands and logged areas has partially offset these losses, keeping the net carbon flux in the tropics close to neutral.
■ Temperate forests, on the other hand, have shown a 30% increase in their carbon sink capacity. This rise is largely due to extensive reforestation efforts, particularly in China.
“Our research team analyzed data from millions of forest plots around the globe,” Pan explained. “What sets this study apart is its foundation in extensive ground measurements – essentially, a tree-by-tree assessment of size, species, and biomass. While the study also incorporates remote sensing data, a common tool in national forest inventories and landsurveys, our unique strength lies in the detailed on-the-ground data collection.”
“The persistence of the global forest carbon sink was a surprise given global increases in wildfire, drought, logging, and other stressors,” according to Birdsey. “But it turns out that increasing emissions in some regions were balanced by increasing accumulation in other regions, mainly re-growing tropical forests and reforestation of temperate forests. These findings support the potential for improving protection and management of forests as effective natural climate solutions.”
The research is co-led by U.S. Department of Agriculture (USDA) Forest Service Northern Research Station Senior Research Scientist Yude Pan and Woodwell Climate Senior Scientist Richard Birdsey, and includes 15 additional co-authors from 11 countries.
Some of the key findings include:
■ Boreal forests in the Northern Hemisphere, spanning regions like Alaska, Canada, and Russia, have experienced a significant decline in their carbon sink capacity, dropping by 36%. This decrease is attributed to factors including increased disturbances from wildfires, insect outbreaks, and soil warming.
■ Tropical forests have also seen a decline, with deforestation causing a 31% decrease in their ability to absorb carbon. However, regrowth in previously abandoned agricultural
The study describes how certain land management policies and practices can help preserve this global carbon sink. According to co-author Professor Oliver Phillips from the University of Leeds, who coordinates the pan-tropical ForestPlots.net coalition of scientists supporting key networks such as AfriTRON and RAINFOR, “the extraordinary persistence of the carbon sink shows that forests have mostly coped with climate change, so far. Deforestation, fire, and logging are damaging forests everywhere, but drought less so. Helping Earth’s forests resist climate change will mean keeping them as intact, healthy and vibrant ecosystems.”
Findings support a focus on curtailing deforestation across all forest biomes, for example, promoting forest restoration on lands that may be unsuitable for agriculture, and improving timber harvesting practices to minimize emissions from logging and related activities. The research also highlights the limitations in data collection, particularly in tropical regions. The study calls for increased research and establishment of more ground sampling plots in these areas to reduce uncertainties in carbon estimates and improve understanding of the global carbon budget.
Christina Shintani Cartographer
Sarah Ruiz Science Writer & Editor
Hurricane season in North America is underway. Already, the second storm of the year to earn a name, Beryl, has cut a destructive swath across the Caribbean and the United States. This year, the National Oceanic and Atmospheric Administration (NOAA) forecasted an extremely active hurricane season, anticipating between 17-25 named storms (the average is 14) and 4-7 major storms (average is 3) that reach category 3 and above with wind speeds exceeding 111 mph.
Intense seasons like this are likely to be a more common occurrence in a warmer world, as higher temperatures, rising seas, and changing weather patterns create the conditions for bigger, more destructive, longer lived, and more rapidly strengthening storms. Here’s how climate change is affecting the Atlantic hurricane season:
2 | The hotter the air, the more water it can hold
To understand how hurricanes are being affected by climate change, it’s important to understand how hurricanes are formed. They are essentially clusters of thunderstorms, building strength as they sweep westward using the energy from warm tropical waters. Under the right conditions, the Earth’s rotation will cause the cluster to spin into a cyclone shape. Because heat is energy, increases in sea surface temperatures play a critical role in strengthening these storms.
The ocean is a major heat sink for the planet, absorbing over 90% of the excess heat trapped by greenhouse gasses in the Earth’s atmosphere over the past few decades. Global sea surface temperatures have increased approximately 2.8°F since the beginning of the 20th century, and ocean heatwaves—large areas of above-normal temperatures that can last for months—are much more common and widespread. A hotter ocean means there is more energy available to fuel tropical storms, ultimately making it a more destructive event when it hits land.
The second thing a hurricane needs to form is moisture. Water is evaporated and pulled up into the developing storm as it spins across warm waters of the tropical Atlantic. Hotter air temperatures mean more moisture can be held as vapor in the atmosphere, which allows storms to ingest greater amounts of water that will eventually condense into clouds and be released as rainfall. Condensation also releases heat into the storm, fueling its intensification. Models estimate that human-caused global warming has increased hurricane extreme hourly rainfall rates by 11%.
3 | ENSO fluctuations are becoming more extreme
Climate change is also contributing to larger swings between the two phases of the El Niño Southern Oscillation (ENSO)— meaning stronger versions of both El Niño or La Niña patterns. Currently, the Atlantic is headed towards a La Niña, which favors hurricane formation because it lessens vertical wind shear. Differences in wind speeds at different heights in the atmosphere can tear a storm apart, while less shear (more consistency in wind speeds between altitudes) allows storms to stay together and build strength.
4 | Tropical storms are undergoing rapid intensification more frequently
All these factors add up to more intense tropical storms in a world altered by climate change—meaning more category 3-5 storms and more big storms back-to-back. Since 1975 the number of category 4-5 cyclones has roughly doubled.
This doesn’t necessarily mean that there will be more hurricanes; however, the ones that do form can be bigger and cause more damage (on top of the already estimated $2.6 trillion in damages since 1980.) If anything, data shows a slight decrease in the number of storms, moving more slowly along their path and releasing extreme wind and rain over a single location for longer periods.
Animations of the map above of hurricanes reaching category 4 or 5 between 1950 and July 2024, and for ENSO fluctuations (left) can be found on the website article page: woodwellclimate.org/how-climate-change-is-affecting-hurricanes
5 | Rising sea levels are making hurricanes more deadly
Sea level rise due to climate change has also made hurricanes a more dangerous threat for more people. As sea levels rise, coastlines are put at increased risk of flooding.
Sea levels have risen roughly 8 inches since the late 19th century, and the rate of rise is accelerating as climate change worsens. When a hurricane makes landfall, water is pushed inland by high-speed winds in an event known as storm surge. Every additional inch of sea level rise allows the surge to travel farther inland, threatening a wider area and causing more damage, death, and injury. This is especially true in areas where increasing human development along the coast has exposed more people and homes to greater risk.
As temperatures continue to rise, communities along the East and Gulf coasts can expect to be hit harder by destructive storms. Despite this, more and more people are choosing to live and build near the shore, increasing the cost of damages when hurricanes strike. Slowing warming temperatures and building adaptation measures to protect coastal communities will become more urgent as Atlantic hurricanes intensify.
Margaret Lin Communications Manager
The first round of 2025 Fund for Climate Solutions (FCS) awardees has been announced. The FCS advances innovative, solutionsoriented climate science through a competitive, internal, and cross-disciplinary funding process. Generous donor support has enabled us to raise more than $10 million towards the FCS, funding 69 research grants since 2018. The latest cohort of grantees includes three projects focused on driving impact through collaboration and community-building, and three projects exploring new horizons in technology with timely policy relevance.
Arctic wildfire pollutants: Towards improving emissions estimates and developing tribally-led monitoring
Lead: ScottZolkos
Collaborators:BrendanRogers,SueNatali,KyleArndt,EliseSunderland (HarvardUniversity)
Increasing wildfire activity in northern high-latitude regions is threatening global climate goals and public health. When organic matter in soils and vegetation burns, greenhouse gasses, fine particulates (PM2.5), and contaminants including mercury are released to the environment. Currently, there is sparse data for understanding how wildfires contribute to the northern mercury cycle, as well as gaps in infrastructure for monitoring PM2.5 in Alaska Native communities. This project will develop a network to measure and monitor the release of mercury and PM2.5 from wildfire, with an emphasis on peatlands. Leveraging ongoing work by Permafrost Pathways, the team will install mercury sampling equipment on existing eddy covariance flux towers across Alaska and Canada. Alongside Permafrost Pathways and their tribal partners, the team will also consult with Alaska Native communities in the Yukon-Kuskokwim Delta to co-develop a tribally-led air quality monitoring program.
Workshop: Innovative sensors and applications in environmental research
Lead:KathleenSavage
Collaborators:ZoëDietrich,MarciaMacedo
Many of the Woods Hole science community’s cuttingedge researchers, including several scientists at Woodwell Climate, are developing creative, do-it-yourself (DIY) tools using relatively simple components to further explore their research questions. However, despite the six institutions’ similar applications and geographic proximity, there are few opportunities for exchange and knowledge, both across Woods Hole institutions and more broadly with Cape Cod educational institutions. The project team will convene a one-
day workshop to bring together aquatic, atmospheric, and terrestrial science researchers and educators from the Woods Hole science community and local community colleges. The event will focus on three main themes: development of new sensor systems that use existing technologies in novel ways; new data storage or transmission solutions; and community initiatives to facilitate continued creation and sharing of new technologies. Sessions will foster knowledge exchange, build networks, and develop community resources focused on innovative DIY research solutions, and a hybrid virtual option will be offered for oral presentations to broaden participation.
Lead:José Lucas Safanelli
Collaborator:Jonathan Sanderman
The Soil Spectroscopy for Global Good (SS4GG) initiative is a collaborative network of hundreds of soil scientists and others focused on using soil spectroscopy as a means to generate highquality soil data at significantly reduced costs. It was created in 2020 by the Woodwell Climate Research Center, the University of Florida, and the OpenGeoHub Foundation (the Netherlands) with support from many national and international institutions and researchers. SS4GG created and supports the Open Soil Spectral Library (OSSL), an open source of soil spectroscopy data, and a broad community of practitioners uses the library and collaborates on related science. This award will extend the activities of the SS4GG initiative with a focus on training and further engagement with the soil science community. The project team will continue to add data sets and new models to the OSSL, as well as engage with the soil science community by attending international conferences and providing a training workshop. The funds will also support hosting a visiting soil biogeochemist at the Woodwell Climate campus—Dr. Raj Setia from the Punjab Remote Sensing Center.
Lead:TaniyaRoyChowdhury
Collaborator:Jonathan Sanderman
Sequestering, or capturing carbon in soils has a high potential to mitigate climate change. It is challenging to specifically predict how successful carbon sequestration may be, as current models used to evaluate agronomic management oversimplify soil microbial properties. This project will test for the key pathways of carbon transformations using soil samples taken under cover crops from a long-term study site. The team will quantify the chemical diversity of carbon substrates that microbes in the soil take up, and use data mining to predict the impacts of that diversity on soil carbon sequestration and nutrient cycling. The research outcomes will also lay a foundation for future collaborative research within the Department of Energy scientific community, and the soil health research community more broadly.
Lead: Seth Gorelik
Collaborator:WayneWalker
The protection, improved management, and restoration of forests are key nature-based solutions to the climate crisis, yet implementation and maintenance of these forest-based solutions requires sustainable and substantial financing. The voluntary carbon market (VCM) has the potential to deliver the necessary level of financing; however, a significant gap exists between its potential and actual performance. Improving the
President and CEO Dr. Max Holmes was quoted in a Mongabay article about the need for better governance of geoengineering experimentation.
Dr. Manoela Machado explained the challenges of containing fires in the Amazon in a widely syndicated Reuters story about disproportionate carbon emissions from forest degradation.
Bloomberg quoted Dr. Jen Francis on the likelihood of continuing summer extremes driven by ocean heat waves.
The Washington Post quoted Dr. Skee Houghton in a story about how forests’ wilting and burning is degrading the ability of the land to store carbon.
Phys.org published a press release from Northern Arizona University, which quoted Dr. Sue Natali on how a warming Arctic is releasing more carbon from permafrost areas, and accelerating climate change. An Earth.com story covering the same issue reprinted Sue’s quote.
accuracy of forest carbon monitoring is crucial for the VCM to deliver effective, meaningful climate change mitigation. This project will enhance the credibility and effectiveness of forest carbon markets by evaluating new remote sensing methods for measuring forest carbon and showing that these methods provide more robust data than the conventional approach. Research findings could lead to updated global standards and policies for issuing carbon credits, which would increase market confidence and promote sustainable forest management.
Lead:Andrea D. deAlmeida Castanho
Collaborators:MichaelCoe,MarciaMacedo
In recent decades, extreme drought events have increased forest flammability, fire severity, and the likelihood of fire escaping and spreading into adjacent forests and working lands, as illustrated by the wildfires seen throughout Amazonia during the 2023–24 drought. The project team will explore the potential of using river stage (water level) data as a proxy for landscape dryness, to ultimately reveal the short-term risk of wildfires spreading into forests. If confirmed, this innovative hypothesis could provide the scientific basis for developing new metrics of river stage to improve early-warning systems that forecast high fire risk days to weeks in advance. These improvements would create benefits not only for tropical forest protection, but also for biodiversity, greenhouse gas emissions, and human health.
Mongabay quoted Dr. Foster Brown in an article about how communities in Acre, Brazil are facing drinking water shortages due to drought.
A press release from Senator Ed Markey’s office announcing legislation to improve longer-term weather and climate forecasting quoted Dave McGlinchey on the importance of funding support for this science.
Dr. Foster Brown provided a briefing to Amazonia Real, and was subsequently quoted in two stories—one about Amazon rivers drying up earlier than expected, and another on the impact of Acre’s extreme drought on Indigenous communities.
Dr. Rich Birdsey was quoted in a widely-syndicated Reuters story reporting on a study that found the world’s forests did less to curb 2023’s carbon emissions. New Hampshire Public Radio also published a story quoting Rich, which covered the debate sparked by a logging project in White Mountain National Forest.
