A study has shown how the light-absorbing properties of brown carbon in the Arctic atmosphere change during atmospheric transport. It is a field observation-based, quantitative analysis of the climate impact of brown carbon, long cited as one of the uncertainties in climate models.
A team led by senior researcher Park Ji-yeon at the Korea Polar Research Institute (KOPRI) Ocean and Atmosphere Research Division said on the 1st that it collected aerosol samples at the Gruvebadet Observatory near the Arctic Dasan Station from May 2022 to Apr. 2023 and analyzed the light-absorbing properties of brown carbon. The findings were published in the September issue of the Journal of Hazardous Materials.
Aerosols in the atmosphere generally reflect sunlight and cool the Earth, but among aerosol components, the sooty "black carbon" and the brown "brown carbon" absorb light and offset this cooling effect. In particular, it has been difficult to calculate the exact climate impact of brown carbon because its absorption properties change as it reacts with light in the atmosphere.
The study found that the annual average light absorption of brown carbon was about 15% of that of black carbon. The team said that if the absorption effect of brown carbon is reflected in climate models, the overall cooling effect of aerosols could be smaller than previously estimated.
By season, the influence of pollutants from human activities in midlatitude regions was pronounced in winter and early spring. The team said this is the first time brown carbon has been subdivided by characteristics to analyze changes in light absorption due to photochemical reactions.
Senior researcher Park Ji-yeon said, "Depending on how the photochemical changes of brown carbon are reflected in climate models, the climate effect may differ," adding, "These results could be used to reduce uncertainty in climate models."
References
Journal of Hazardous Materials (2026), DOI: https://doi.org/10.1016/j.jhazmat.2026.143086