Global CO2 Emissions from Forest Fires Surge by 60%, Driven by Climate Change
A new study has revealed a dramatic surge in carbon dioxide (CO2) emissions from forest fires, with levels rising by 60% globally since 2001. This increase, which has nearly tripled in some of the world's most climate-sensitive northern boreal forests, emphasizes the growing threat of wildfires fueled by changing climate conditions. The findings, published in Science by a research team from the University of East Anglia (UEA), present crucial insights into how wildfires are reshaping global carbon dynamics.
By categorizing regions of the world into 'pyromes'—areas where forest fire patterns are influenced by similar environmental, human, and climatic factors—the researchers identified the key drivers behind the recent surge in forest fire activity. This comprehensive approach marks one of the first global studies to distinguish between forest and non-forest fires, shedding light on how boreal forests in Eurasia and North America have seen fire-related emissions almost triple between 2001 and 2023.
Beyond boreal regions, the study also highlights a broader pattern of increased emissions across extratropical forests, with an additional half a billion tonnes of CO2 released annually. This shift has moved the epicenter of fire-related emissions from tropical forests to extratropical regions, where hot, dry conditions during heatwaves and droughts, combined with rapid vegetation growth, have exacerbated fire risks. The accelerated warming in high northern latitudes, where temperatures rise at twice the global average, has only intensified these trends.
Another alarming finding from the research is the growing severity of wildfires over the past two decades. The carbon combustion rate—a key measure of fire severity based on the amount of carbon released per unit area burned—has surged by nearly 50% in forests worldwide since 2001. This increase in fire intensity underscores the urgent need for climate action, with the international team of scientists calling for immediate efforts to curb fossil fuel emissions to prevent further wildfire escalation.
Lead author Dr. Matthew Jones of UEA's Tyndall Centre for Climate Change Research noted: "Increases in both the extent and severity of forest fires have led to a dramatic rise in the amount of carbon emitted by forest fires globally. Startling shifts in the global geography of fires are also underway, and they are primarily explained by the growing impacts of climate change in the world's boreal forests." His message underscores the critical need to address global warming to protect vulnerable forest ecosystems from future wildfire devastation.
Forests play a crucial role in storing carbon and mitigating climate change, and their health is vital for meeting international climate goals. Reforestation and afforestation efforts depend on forests maintaining their carbon storage capacity. However, the study shows that wildfires are threatening this balance, as extratropical fires alone now emit an extra half a billion tonnes of CO2 annually compared to two decades ago. The long-term impact depends on how well forests recover after these increasingly severe blazes.
"The steep trend towards greater extratropical forest fire emissions is a warning of the growing vulnerability of forests and it poses a significant challenge for global targets to tackle climate change," warned Dr. Jones. He stressed the importance of closely monitoring how post-fire recovery will influence forests' ability to store carbon in the future.
Interestingly, the rise in forest fire emissions contrasts with a reduction in fires across tropical savannahs, where overall burned area has decreased by a quarter globally since 2001. While previous studies suggested a decline in fire activity, the new findings highlight the more dangerous nature of forest fires, which release more harmful smoke than grassland fires and pose greater threats to human health and ecosystems.
Dr. Jones emphasized that this shift in fire patterns has been masked until now: "Reduced burning in the already fire-prone savannahs and grasslands has masked increases in forest fire extent and severity that are hugely consequential for society and the environment." This shift reveals that fires are increasingly encroaching on forested areas, where they pose the greatest risks to people and critical carbon stores.
The study also broke new ground by using machine learning to group global forest ecoregions into 12 distinct pyromes, helping researchers isolate the effects of climate change from other factors like land use. This approach provided key insights into which wildfire management strategies can best protect forests from the rising threat of fires. Dr. Jones called for substantial funding to support proactive forest management and fire mitigation strategies, including managing fuel loads and implementing fire breaks in high-risk areas.
