Microplastics found in clouds could affect weather and global temperatures

Scientists in eastern China find 24 out of 28 water samples have plastic particles commonly seen in synthetic fibers and packaging

Air, water, soil, food and even blood – microplastics have found their way virtually everywhere on Earth, and now that list includes clouds.

Bits of plastic particles were recently discovered above eastern China, with new research showing that these microplastics could influence cloud formation and the weather.

A group of scientists from Shandong University in China collected cloud water atop Mount Tai, finding microplastics in 24 out of 28 samples. They include polyethylene terephthalate (otherwise known as PET), polypropylene, polyethylene and polystyrene, all particles commonly found in synthetic fibers, clothing and textiles, as well as packaging and face masks.

“This finding provides significant evidence of the presence of abundant MP’s [microplastics] in clouds,” the researchers stated in the paper published today in Environmental Science and Technology Letters.

Earlier this year, a study out of Japan showed that microplastics were present at the peak of Mount Fuji and Mount Oyama, suggesting that the particles may have originated from plastics in the ocean and been transported via air masses. The concentration of microplastics in Mount Tai cloud water was up to 70 times that of Japan’s mountains’ cloud water.

“Most pollution we tend to think of is in liquid form,” said Fay Couceiro, a professor of environmental pollution at the University of Portsmouth. “We tend to think of that going into the river and the sea. Whereas microplastics, because they are a physical particle, are not following the normal rules. We’re finding microplastics in these pristine environments at the tops of these extremely hard-to-reach mountains.”

So, how are they getting there?

Other than contamination from people visiting these sites, the particles may be transported through the air. Samples from low-altitude and denser clouds had larger amounts of microplastics in them.

Aged plastics – in other words, ones that have already been weathered from ultraviolet radiation – were smaller in size and had rougher surfaces. They also contained more lead, mercury and oxygen compared to pristine, untouched plastics. Scientists found that clouds can modify microplastics, possibly resulting in these particles affecting cloud formation.

“Cloud formation has a huge implication for not just our local weather patterns, but for our global temperatures,” said Couceiro, who was not involved in the study.

Clouds affect the climate in a plethora of ways. They produce precipitation and snow, affecting global rainfall and vegetation. Clouds block sunlight, cooling the surface of the planet and providing shade on the ground. But they can also trap heat and humidity, subsequently warming the air.

The study authors state that more research is needed to fully determine the impact of microplastics on the weather, but what remains clear is that more can be done to address this.

“There’s only one group of animals on this planet that use plastic, and that’s us human beings,” said Couceiro. “We really need a global response to this, as it’s not going to be solved by a single country, because air doesn’t respect boundaries.”


Photograph: Costfoto/NurPhoto/Shutterstock