The study, published in the journal Nature Geoscience, found that smoke aerosols can alter the properties of clouds, making them more reflective and increasing their ability to reflect sunlight back into space. This cooling effect can offset some of the warming effects that smoke particles directly cause by absorbing sunlight.
"Our findings challenge the traditional view of smoke as a climate warmer, and suggest that its overall effect on climate may be more nuanced," said lead author Dr. Johannes Veres, a research fellow at the University of Leeds.
Biomass burning, such as wildfires and agricultural fires, releases large amounts of smoke aerosols into the atmosphere. These aerosols consist of tiny particles that can scatter sunlight, alter cloud properties, and affect precipitation.
Previous studies have shown that smoke aerosols can have both warming and cooling effects on climate. The warming effect is caused by the direct absorption of sunlight by smoke particles. The cooling effect is caused by the interaction between smoke aerosols and clouds, which can lead to increased cloud reflectivity and reduced precipitation.
The new study used satellite observations and climate model simulations to investigate the interactions between smoke aerosols and clouds. The researchers found that the cooling effect of smoke aerosols on clouds was stronger than previously thought, and that it could offset a significant portion of the warming effect caused by the direct absorption of sunlight.
"This study provides new insights into the complex interactions between smoke aerosols and clouds, and suggests that the climate impacts of biomass burning may be more nuanced than previously thought," said co-author Dr. Piers Forster, a climate scientist at the University of Leeds.
The researchers say that more studies are needed to better understand the interactions between smoke aerosols and clouds, and to quantify the overall effect of biomass burning on climate.
