Shape matters: long-range transport of microplastic fibers in the atmosphere
arxiv(2023)
摘要
Deposition of giant microplastic particles from the atmosphere has been
observed in the most remote places on Earth. However, their deposition patterns
are difficult to reproduce using current atmospheric transport models. These
models usually treat particles as perfect spheres, whereas the real shapes of
microplastic particles are often far from spherical. Such particles experience
lower settling velocities compared to volume-equivalent spheres, leading to
longer atmospheric transport. Here, we present novel laboratory experiments on
the gravitational settling of microplastic fibers in air and find that their
settling velocities are reduced by up to 76
volume. An atmospheric transport model constrained with the experimental data
shows that shape-corrected settling velocities significantly increase the
horizontal and vertical transport of particles. Our model results show that
microplastic fibers of about 1 mm length emitted in populated areas can reach
extremely remote regions of the globe, including the High Arctic, which is not
the case for spheres. We also calculate that fibers with lengths of up to 100
μm settle slowly enough to be lifted high into the stratosphere, where
degradation by ultraviolet radiation may release chlorine and bromine, thus
potentially damaging the stratospheric ozone layer. These findings suggest that
the growing environmental burden and still increasing emissions of plastics
pose multiple threats to life on Earth.
更多查看译文
AI 理解论文
溯源树
样例
![](https://originalfileserver.aminer.cn/sys/aminer/pubs/mrt_preview.jpeg)
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要