CLIMATEWIRE | According to a recent report affiliated with the United Nations, carbon markets that are designed to fund the conservation of forests and the planting of new trees might be exacerbating climate change by increasing the risk of large wildfires, which release significant amounts of greenhouse gases.

Forests have traditionally been viewed as crucial battlegrounds in the fight against climate change due to their ability to absorb carbon emissions. However, this perspective is shifting, as indicated by a May report from the United Nations University Institute for Water, Environment and Health (UNU-INWEH), a scholarly branch of the U.N.

Over the last decade, wildfires of unprecedented magnitude have broken out in regions like Canada, Australia, Siberia, and the Amazon rainforest. Recently, forest fires have led to the evacuation of thousands in the Canadian provinces of Manitoba and Alberta.

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“Forests and peatlands are increasingly becoming massive sources of carbon emissions worldwide due to more frequent wildfires,” the report states. It notes that climate policies and carbon-offset initiatives often overlook these significant emissions.

The report points out a major flaw in a key global approach to combating climate change—tree planting and preservation. This strategy has attracted billions in funding from polluters seeking to offset their emissions through the voluntary carbon market, a system that has faced growing criticism for its lack of regulation.

Recent devastating wildfires have had severe impacts. For instance, the 2023 wildfires in Canadian forests released more greenhouse gases than the total industrial emissions of any nation other than China and India, according to Ju Hyoung Lee, a research fellow at UNU and the report’s lead author, speaking from Seoul, South Korea.

In California, the 2024 wildfires destroyed significant areas of forests intended for carbon storage under the state’s cap-and-trade carbon market program.

The report criticizes the lack of systematic monitoring of forest health, suggesting that without such measures, the voluntary carbon market and other forest-centric policies could inadvertently heighten wildfire risks.

Furthermore, planting additional trees to capture carbon might backfire, the report argues, as climate change-related increases in heat and carbon dioxide could accelerate forest growth while simultaneously drying out the soil.

“Increasing tree planting for carbon mitigation in such conditions may likely lead to higher carbon emissions from future wildfires,” the report cautions.

When assessing the risk of wildfires, entities certifying forest projects in the voluntary carbon market typically rely on historical data. However, Lee notes, “Forests are changing, and they will not resemble what they were like over the past two decades.”

Lee mentions that often the most recent five years, which have witnessed some of the worst fires, are omitted from historical data analyses.

Consequently, organizations like Verra, which set standards for and certify climate projects on the voluntary market, tend to underestimate fire risks, according to Lee. Verra did not respond to a request for comment.

Concerns about the evolving dynamics of forests have been raised for over a decade, says Kaveh Madani, director of UNU-INWEH, in an interview from Toronto.

Madani hopes the report will convey that existing forest programs and certification standards, based on now-outdated science, “can increase the risk of emissions in some cases.”

He emphasizes, however, that not all forest programs in the voluntary carbon market and beyond pose a wildfire threat.

The paper advocates for reforms in the voluntary carbon market and similar systems to better account for current forest conditions and to avoid unintended consequences like more wildfires.

It suggests that rainfall, soil health, and potential future droughts and heatwaves should be considered before approving forest projects as solutions for reducing carbon emissions. Satellite observations could help identify areas where forest growth is leading to fuel accumulation, potentially excluding them from carbon markets due to the high risk of emissions from future fires.

“The risk of wildfire and other environmental conditions that could harm forests must be incorporated into our future planning and the strategies we implement,” Madani stated.

Reprinted from E&E News with permission from POLITICO, LLC. Copyright 2025. E&E News provides essential news for energy and environment professionals.