A new study reveals that microplastics are disrupting the ocean's vital role in absorbing carbon dioxide, potentially exacerbating global warming. Researchers highlight how these tiny particles interfere with marine organisms and release greenhouse gases. The findings call for urgent global action to address plastic pollution alongside climate efforts.
Scientists have uncovered a concerning link between microplastics and climate change in a study published in the Journal of Hazardous Materials: Plastics. Titled "From pollution to ocean warming: The climate impacts of marine microplastics," the research, led by Dr. Ihsanullah Obaidullah from the University of Sharjah, examines how these particles less than five millimeters in size affect oceanic carbon cycles.
Microplastics, found in deep ocean waters, air, soil, and even the human body, pose risks by carrying toxins and disrupting ecosystems. The study, a collaborative effort involving experts from China, Hong Kong, Pakistan, and the United Arab Emirates, reviewed 89 peer-reviewed articles mainly from after 2015. It identifies disruptions to the "biological carbon pump," where phytoplankton and zooplankton transfer carbon from the atmosphere to deep sea layers.
"Microplastics disrupt marine life, weaken the 'biological carbon pump,' and even release greenhouse gases as they degrade," Dr. Obaidullah explained. The particles impair phytoplankton photosynthesis and zooplankton metabolism while fostering a "plastisphere"—a microbial community on plastic surfaces that boosts greenhouse gas production through activities in nitrogen and carbon cycles.
Oceans serve as Earth's largest carbon sink, but microplastics threaten this function, potentially leading to warming, acidification, biodiversity loss, and risks to food security and coastal communities. The researchers note that over 400 million tonnes of plastic are produced annually, with half for single use and less than 10 percent recycled. Without changes, production could triple by 2060, and humans have already generated more than 8.3 billion tonnes, 80 percent of which ends up in landfills or the environment.
The authors advocate integrating plastic pollution into the United Nations' Sustainable Development Goals, improving waste management, promoting biodegradable alternatives, and using AI for monitoring. "Tackling plastic pollution is now part of the fight against global warming," Dr. Obaidullah stated. They emphasize coordinated policies to mitigate long-term effects on ocean health.