Study finds northern wildfires may release far more ancient carbon than models estimate
Feb 27th 2026
A UC Berkeley-led team used detailed national data and field measurements to reconstruct carbon emissions from 324 Swedish wildfires and found that common global models often miss large releases of ancient carbon from smoldering peat and organic soils.
- UC Berkeley researchers reconstructed emissions from 324 Swedish wildfires in 2018 and published the results in Science Advances.
- Field sampling at 50 burned sites showed fires can burn into deep organic soils and peat, releasing carbon accumulated over centuries.
- Widely used global fire models underestimated emissions from peat-rich areas by as much as 14 times in Dalarna while overestimating emissions in drier, high-intensity fires such as in Gävleborg.
- Smoldering of organic soils can emit carbon for weeks to years, meaning fires that look minor from satellites can be climatically large.
- Authors say missing ground measurements from regions like Siberia could mean global wildfire carbon estimates are too low and plan to apply these methods to other regions including the US West.