Plastics have long been recognized as a significant threat to ecosystems and biodiversity. However, a recent research reveals that the dangers of plastic extend beyond terrestrial environments, infiltrating the atmosphere and even clouds.
A research team from Pennsylvania State University has identified microplastic particles smaller than 5 millimeters in the atmosphere. Their findings were published in the Environmental Science & Technology (ES&T) journal on November 7, 2024.
Microplastics Spread Beyond the Earth’s Surface
Microplastics have become a familiar concern for researchers and scientists, having been detected in diverse environments, from mountaintops to sea turtles' stomachs, plant roots, and even human brains. The recent discovery of microplastics in clouds has prompted further investigation into their interactions with the climate system. This is particularly significant since microplastics influence cloud formation, which impacts rainfall patterns, climate modeling, and aviation safety.
How Microplastics Alter Freezing Temperatures in Clouds
The researchers examined four types of microplastics: low-density polyethylene (LDPE), polypropylene (PP), polyvinyl chloride (PVC), and polyethylene terephthalate (PET). These materials were introduced into small water droplets, which were then gradually cooled to study their effects on ice formation.
Normally, atmospheric water droplets freeze at -38 degrees Celsius. However, in this study, droplets containing microplastics froze at temperatures 5 to 10 degrees Celsius higher than those without plastic.
The team concluded that the presence of insoluble materials in water droplets causes them to freeze at higher temperatures. When these microplastics mix with clouds, they disrupt weather and climate patterns, particularly in clouds containing both liquid and frozen water. As microplastic-laden droplets ascend and cool, they alter freezing temperatures, influencing rainfall amounts and weather systems.
Despite the many benefits plastics provide, it is critical for humans to reduce their consumption due to their far-reaching and harmful impacts on the environment and human well-being.
