Restructuring the clouds themselves: scientists have identified an unexpected culprit behind climate change.

A new study by scientists has revealed that microplastics present in the air can alter cloud formation, potentially impacting weather and climate. Clouds form when water vapor adheres to airborne particles, often dust, creating ice crystals or water droplets. However, researchers found that microplastic particles can serve a similar purpose, promoting the formation of ice crystals at temperatures significantly warmer than usual—up to 10 degrees Celsius higher than in clouds without microplastics, according to The Conversation.

The findings, published in the journal ACS EST Air, led scientists to suggest that clouds could form under conditions where they typically do not, which may change the nature of precipitation. The study focuses on the nucleation process—a natural phenomenon in the atmosphere where water vapor turns into ice upon contact with solid particles. While mineral dust and biological particles, such as pollen, have traditionally contributed to nucleation, microplastics, which are less than five millimeters in size and widely distributed globally, prove to be equally effective in this role, says Miriam Friedman, a chemistry professor at Penn State University.

Researchers tested four common plastics, including low-density polyethylene and polypropylene, and noted that half of the droplets containing microplastics froze at -22 degrees Celsius. Environmental factors such as ultraviolet radiation, ozone, and acids influenced ice formation but did not eliminate it, indicating that even chemically altered microplastics can affect cloud composition. These clouds play a crucial role in regulating Earth's climate by reflecting sunlight and trapping heat.

The ratio of liquid and ice particles in clouds affects how much sunlight is reflected back into space or absorbed, influencing Earth's temperature balance. An increase in the number of ice particles due to the presence of microplastics could disrupt this balance, potentially altering the cooling and warming effects of clouds. Thus, microplastics may introduce additional uncertainty into meteorological measurements, as they can contribute to the formation of more ice clouds, affecting both precipitation and heat regulation.

Scientists emphasize that further studies are needed to understand the concentration of microplastics in atmospheric layers where clouds form. They also require data comparing microplastic levels with levels of other ice-forming particles, such as mineral dust and biological materials. The ability to accurately model the impact of microplastics will depend on a better understanding of their abundance and distribution in the atmosphere.

Unfortunately, microplastic pollution is ubiquitous and has been detected even in remote locations such as Antarctica and Everest, reflecting the scale of its distribution in our planet's atmosphere. These particles enter our everyday environment, including the air we breathe and the food we consume, raising concerns about both their ecological impact and their potential negative effects on our health.