Although scientists have long worried about microplastics contaminating air, food and water, new research reveals a previously unknown threat: Tiny pieces of airborne plastic are heating the planet.
Reporting in Nature Climate Change , an international research team found that colored microplastics in the air trap heat by absorbing light, thereby warming the atmosphere. Plastic debris can become airborne when plastic products break down into miniscule bits swept up by wind and water spray.
Researchers have long known that some floating particles, called aerosols, contribute to climate change. Soot, for example, is an aerosol that contains black carbon, one of the planet's most potent warming agents.
"This research expands the family of aerosols that are actually causing warming, and that makes [microplastics] a particularly good target," for climate action, says coauthor Drew Shindell, Nicholas Distinguished Professor of Earth Science at Duke University's Nicholas School of the Environment, who led the study in collaboration with researchers at Fudan University in China.
Old climate models indicated that airborne microplastics — which researchers assumed to be colorless — were negligible contributors to warming. Indeed, colorless atmospheric aerosols, such as water droplets in clouds, actually cool the planet by reflecting sunlight away from Earth.
Shindell's research tells a different story.
Using computer simulations and lab experiments, the team analyzed how light and heat interact with tiny bits of plastic. They found that these particles come in varied colors that intensify with age. Those hues give this debris warming power: Pigmented microplastics absorb roughly 16% as much heat as black carbon.
To put this in perspective, microplastics in the atmosphere have approximately the same warming effect as running 200 coal-fired power plants annually, according to Shindell.
"Targeting microplastics is not going to solve our climate problem by any means," he says, but removing the equivalent of 200 coal-fired power plants "would be a nice contribution to getting our [carbon dioxide] down."
The researchers also used their data to predict where these airborne microplastics exist globally. Their findings showed that, unlike black carbon, which concentrates largely over land, airborne microplastics congregate over a region of the ocean called the North Pacific Subtropical Gyre. This massive system of ocean currents spans nearly 8 million square miles, collecting plastic debris.
When waves break over this plastic detritus, sea spray launches microplastics into the air. In other words, the gyre is a big source of atmospheric microplastics.
Currently, microplastics don't appear to be a major climate threat, according to Shindell. He hopes his study, which focused on airborne microplastics closest to earth's surface, will inspire other teams to measure microplastics throughout the lower atmosphere for a more complete picture of their effects on warming.
After all, plastic pollution is projected to surge over the next decade. Without significant action — reducing plastic use and waste and improving plastic waste management and recycling — plastic leakage into the environment could increase by 50% from 2020 levels, to 30 million tons by 2040, according to the Organisation for Economic Co-operation and Development.
Shindell says his research could motivate countries to sign the U.N. Plastics Treaty , which calls for an end to plastic pollution.
"We have so much work to do to get down to something like a Paris Agreement," Shindell says, referencing the 2015 pledge by nearly 200 countries to prevent Earth's average temperature from rising more than 2 degrees Celsius above pre-industrial levels. "We really need every single thing at our disposal."
Press release by Gary Thill
Funding: National Natural Science Foundation of China, National Key R&D Program of China, Natural Science Foundation of Shanghai City
Citation: Liu Y, Fu H, Zhang H, et al. " Atmospheric Warming Contributions From Airborne Microplastics and Nanoplastics ." Published in Nature Climate Change on May 4, 2026.
