Smouldering woody debris drives air pollution in the Amazon

Smouldering woody debris drives air pollution in the Amazon
by Erica Marchand
Paris, France (SPX) Jan 29, 2025

A major study funded by the European Space Agency (ESA) has revealed that fire emissions in the Amazon and Cerrado regions are predominantly caused by the smouldering combustion of woody debris. This discovery underscores the critical role that fuel characteristics play in fire emissions, with implications for global carbon cycles, air quality, and biodiversity.

The research addresses uncertainties in fire emission inventories by combining advanced Earth observation methods with innovative modeling techniques.

Using satellite data and fire models, scientists investigated the severe fire season of 2020 in the Amazon and Cerrado biomes of South America. The study integrated detailed data on fuel types, moisture levels, and burning patterns to provide a comprehensive analysis.

Published in Nature Geoscience, the findings are part of the Sense4Fire project, led by Dresden University of Technology (TUD) in collaboration with the Royal Netherlands Meteorological Institute (KNMI), BeZero Ltd., and other research partners.

The study found that woody debris contributes up to 75% of the total burned biomass in these regions, resulting in disproportionately high emissions of carbon monoxide and other air pollutants. It estimated that wildfires in the Amazon during 2020 consumed approximately 372 million tonnes of dry biomass, releasing around 40 million tonnes of carbon monoxide.

"We've demonstrated how the burning of dead wood, especially in tropical forest areas, results in smouldering combustion that produces significantly more carbon monoxide than fires in savannah ecosystems," explained Matthias Forkel, lead author from TUD. "This understanding is crucial for improving fire emission inventories and global climate models."

The study also utilized data from the Copernicus Sentinel-5P mission, analyzed by KNMI, to validate and enhance emission estimates.

Stephen Plummer, ESA Earth Observation Applications Scientist, added, "This research was partially funded by our Science for Society SENSE4FIRE project, so we are very happy to see it bear such important results.

"The findings highlight the significant impact of woody debris in intensifying fire emissions and hence air pollution in fire-prone areas like the Amazon rainforest and Cerrado savannas, where deforestation and human-caused fires are becoming more frequent."

The data supporting the study are publicly accessible through TUD's OPARA data repository here

Research Report:Burning of woody debris dominates fire emissions in the Amazon and Cerrado