The study is published in Environmental Chemistry Letters
(sustainabilityenvironment.com) – Microplastics contained in clouds can influence climate change. On the one hand by acting on cloud formation. On the other by emitting greenhouse gases. This was revealed by a study published in Environmental Chemistry Letters, the first to highlight this dynamic.
Microplastic fragments of this material smaller than 5 millimeters are considered. They are found everywhere, from the ocean depths to the highest mountain peaks, and constitute one of the most pervasive forms of pollution. Not only for their localization but also for the ability, given by the infinitesimal dimensions, to penetrate into the human body, including passing through organic tissues. Microplastics have also been found, for example, in the blood and placenta.
How microplastics behave in the atmosphere
The team of researchers at the Japanese University of Waseda collected and analyzed the drops of water condensed in the clouds around Mount Fuji and Mount Oyama at heights between 1,300 and 3,700 meters. Identifying 9 different types of polymers and one type of rubber. With concentrations of 6.7-13.9 fragments per liter and sizes between 7.1 and 94.6 micrometers.
Most of these plastic polymers are hydrophilic, researchers point out, and can act as nuclei for cloud condensation, thus altering the normal process and speeding it up. With direct consequences for the climate.
The second way in which these microplastics in the atmosphere can affect the climate crisis concerns their presence in the troposphere. In fact, plastic fragments less than 5 millimetres “degrade much faster in the upper atmosphere than on the ground due to strong ultraviolet radiation,” the authors explain. In the degradation process, the bits of plastic “release greenhouse gases and contribute to global warming”.
The study goes no further in determining the scale of the impact of microplastics on climate, neither in the case of the contribution in the rapid formation of clouds nor in the accelerated contribution of greenhouse gases in the atmosphere.
“Microplastics in the free troposphere are transported and contribute to global pollution. If plastic air pollution is not tackled proactively, climate change and ecological risks could become a reality, causing serious and irreversible environmental damage in the future,” the authors conclude.