Microplastics May Accelerate Global Warming by Absorbing Sunlight, Study Finds

Microplastics in the Atmosphere May Be Warming the Planet

Microplastics, which have infiltrated every corner of the globe and even human bodies, may also be accelerating global warming, according to a new study published in Nature Climate Change.

The research, led by scientists at Fudan University in China, found that microplastics absorb more sunlight than they reflect in the atmosphere, resulting in a net warming effect. While less potent than greenhouse gases, the impact is significant enough to warrant attention.

“We can say with confidence that overall they are warming agents. To me, that’s the big advance.”

— Drew Shindell, study coauthor and professor of earth science at Duke University

How Microplastics Contribute to Warming

Until now, the climate impact of microplastics has been largely overlooked, and current climate models do not account for them. The study highlights a previously unconsidered factor: the color of microplastics. Color determines how much light and heat a particle absorbs or reflects—similar to how black leather car seats heat up faster on a sunny day.

The researchers tested how microplastics of different colors and sizes absorb heat in a lab setting and simulated their atmospheric behavior. They found that microplastics could generate up to one-sixth the warming effect of black carbon (soot), with black, yellow, blue, and red particles absorbing the most sunlight.

Shindell told The Washington Post that the annual warming from microplastic pollution is roughly equivalent to the output of 200 coal-fired power plants operating for a year. However, this estimate does not account for long-term effects as particles persist and degrade over decades.

Uncertainty and Further Research

Shindell emphasized that much remains unknown about the quantity and distribution of airborne microplastics, both horizontally and vertically in the atmosphere.

“We still have a lot to learn about exactly how many of these are in the atmosphere and how they’re distributed. This is not the final word.”

Microplastics and Cloud Formation

This study is not the only one examining the atmospheric role of microplastics. Another study found evidence that airborne microplastics could influence cloud formation and, consequently, weather patterns. The particles provide surfaces for water droplets to cling to, potentially altering ice crystal formation in clouds.

Broader Climate Concerns

For more on the accelerating impacts of climate change, read: Climate Change Is Reducing the Nutritional Value of Food.