Norwegian Institute for Air Research (NILU), Instituttveien 18, 2007 Kjeller, Norway.
The Czech Academy of Sciences, Institute of Information Theory and Automation, Prague, Czech Republic.
J Hazard Mater. 2022 Jun 15;432:128585. doi: 10.1016/j.jhazmat.2022.128585. Epub 2022 Feb 26.
We combine observations from Western USA and inverse modelling to constrain global atmospheric emissions of microplastics (MPs) and microfibers (MFs). The latter are used further to model their global atmospheric dynamics. Global annual MP emissions were calculated as 9.6 ± 3.6 Tg and MF emissions as 6.5 ± 2.9 Tg. Global average monthly MP concentrations were 47 ng m and 33 ng m for MFs, at maximum. The largest deposition of agricultural MPs occurred close to the world's largest agricultural regions. Road MPs mostly deposited in the East Coast of USA, Central Europe, and Southeastern Asia; MPs resuspended with mineral dust near Sahara and Middle East. Only 1.8% of the emitted mass of oceanic MPs was transferred to land, and 1.4% of land MPs to ocean; the rest were deposited in the same environment. Previous studies reported that 0.74-1.9 Tg y of land-based atmospheric MPs/MFs (< 5 mm) are transported to the ocean, while riverine transport is between 3.3 and 14 Tg y. We calculate that 0.418 ± 0.201 Tg y MPs/MFs (size up to 250 and 2500 µm) were transported from the land to ocean (large particles were ignored). Model validation against observations showed that particle removal must be urgently updated in global models.
我们结合了美国西部的观测结果和反演模型，以约束全球大气微塑料（MPs）和微纤维（MFs）的排放。进一步利用后者来模拟它们的全球大气动力学。全球每年的 MPs 排放量估计为 9.6 ± 3.6 吨，MFs 排放量为 6.5 ± 2.9 吨。全球平均每月 MPs 浓度最高可达 47 ng m 和 33 ng m，MFs 浓度最高可达 47 ng m 和 33 ng m。农业 MPs 的最大沉积发生在世界上最大的农业区附近。道路 MPs 主要沉积在美国东海岸、中欧和东南亚；与矿物灰尘一起重新悬浮的 MPs 则在撒哈拉沙漠和中东附近。只有 1.8%的海洋 MPs 排放质量转移到陆地，1.4%的陆地 MPs 转移到海洋；其余的则沉积在同一环境中。先前的研究报告称，有 0.74-1.9 吨 y 的陆地大气 MPs/MFs（<5 毫米）被输送到海洋，而河流输送量则在 3.3 至 14 吨 y 之间。我们计算出，有 0.418 ± 0.201 吨 y MPs/MFs（尺寸最大可达 250 和 2500 µm）从陆地输送到海洋（忽略大颗粒）。对观测结果的模型验证表明，必须紧急更新全球模型中的颗粒去除。
