13 hours ago

Airborne Microplastics May Be Warming the Planet

Tiny particles of plastic amassing in the atmosphere may be intensifying warming, according to new study.

Microplastics shed by synthetic fabrics, rubber tires, plastic bags, bottles, and other goods as they break down have contaminated the world’s seas, soils, and sky, research has found. Scientists have previously shown that microplastics can travel thousands of miles through the atmosphere and seed clouds, which means they have the potential to influence temperature and rainfall.

The new study adds another dimension to the climate risks from microplastics. It shows that darker bits of plastic are absorbing heat. And even though lighter particles are reflecting sunlight, with a cooling influence, in the aggregate microplastics are having a warming effect, according to the study, published in Nature Climate Change. The finding holds even when accounting for how colors may change or fade with time.

The warming impact is tiny, far less than the impact of carbon dioxide emissions, and only a fraction of the impact of soot. The microplastic emissions produced globally each year have roughly the same warming effect as running 200 coal power plants for that year, the study’s authors told The Washington Post.

Researchers say that climate models may need to be updated to account for the warming effect of plastic, but the new study is far from conclusive.

“We know that plastic pollution causes microplastic and nanoplastic particles to be transported in our atmosphere,” said Sam Harrison, U.K. Centre for Ecology & Hydrology, who was not involved in the study. “We need more evidence before we can confidently conclude the impacts of plastics on climate change.”