According to estimates, by 2040 the level of plastic pollution could reach 80 million metric tons per year. Plastic particles have now been detected in virtually all spheres of the environment, e.g. in water bodies, the soil and the air. Via ocean currents and rivers, the tiny plastic particles can even reach the Arctic, Antarctic or ocean depths. A new overview study has now shown that wind, too, can transport these particles great distances – and much faster than water can: in the atmosphere, they can travel from their point of origin to the most remote corners of the planet in a matter of days. In the journal Nature Reviews Earth and Environment, an international team of researchers – including experts from the Alfred Wegener Institute, the Institute for Advanced Sustainability Studies in Potsdam, and the GEOMAR Helmholtz Centre for Ocean Research in Kiel – describes how microplastic finds its way into the atmosphere and how it is subsequently transported.
Today, between 0.013 and 25 million metric tons of micro- and nanoplastic per year are transported up to thousands of kilometres by ocean air, snow, sea spray and fog, crossing countries, continents and oceans in the process. This estimate was arrived at by an international team of 33 researchers, including experts from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI), the Institute for Advanced Sustainability Studies in Potsdam (IASS) and the GEOMAR Helmholtz Centre for Ocean Research in Kiel.
“Air is a much more dynamic medium than water,” says co-author Dr Melanie Bergmann from the AWI. “As a result, micro- and nanoplastic can much more quickly penetrate those regions of our planet that are most remote and still largely untouched.” Once there, the particles could affect the surface climate and the health of local ecosystems. For example, when these darker particles are deposited on snow and ice, they affect the ice-albedo feedback, reducing their ability to reflect sunlight and promoting melting. Similarly, darker patches of seawater absorb more solar energy, further warming the ocean. And in the atmosphere, microplastic particles can serve as condensation nuclei for water vapour, producing effects on cloud formation and, in the long term, the climate.
Read more at: Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research
Plastic trash, washed ashore at the Sylt west beach (Photo Credit: Sina Löschke)