Microplastics in Atmosphere May Contribute to Climate Change

New research published in Nature Climate Change on May 4 reveals that airborne microplastics and nanoplastics could be contributing to global warming. The study, led by environmental scientist Yu Liu at Fudan University in China, found that colorful plastic particles absorb more sunlight than they reflect, heating the surrounding air. At a wavelength of green light, pigmented particles absorbed nearly 75 times more light than non-pigmented ones. Computer simulations indicate these plastics contribute about one-sixth the warming effect of black carbon (soot), a major air pollutant from fossil fuels. Microplastics (under 5 mm) and nanoplastics (under 1 mm) originate from textiles, tires, and consumer products. The study is the first to quantify their potential climate impact, though experts caution that laboratory conditions differ from real-world complexity. Gilberto Binda of the University of Insubria notes major uncertainties remain due to lack of comprehensive atmospheric data. Ria Devereux of the University of East London points out that real-world degradation involves humidity, chemicals, and wave action, not just UV light. Andreas Stohl of the University of Vienna suggests another decade of studies is needed for firm conclusions. The findings underscore that microplastics are not just an environmental contamination issue but an emerging climate factor.