Exploring the Transport Path of Oceanic Microplastics in the Atmosphere

Author(s)
Silvia Bucci, Lucie Bakels, Camille Richon
Abstract

Microplastics (MP) have been recognized as an emerging atmospheric pollutant, yet uncertainties persist in their emissions and concentrations. With a bottom-up approach, we estimate 6-hourly MP fluxes at the ocean-atmosphere interface, using as an input the monthly ocean surface MP concentrations simulated by the global oceanic model (NEMO/PISCES-PLASTIC, Nucleus for European Modeling of the Ocean, Pelagic Interaction Scheme for Carbon and Ecosystem Studies), a size distribution estimate for the MP in the micrometer range, and a sea salt emission scheme. The atmospheric dispersion is then simulated with the Lagrangian model FLEXPART. We identify hotspot sources in the tropical regions and highlight the seasonal variability of emissions, atmospheric concentrations, and deposition fluxes both on land and ocean surfaces. Due to the variability of MP concentration during the year, the MP flux from the sea surface appears to follow a seasonality opposite to that of sea salt aerosol emissions. The comparison with existing observations of MP in the marine atmosphere suggests an underestimation of one to 2 orders of magnitude in our current knowledge of the MP in the oceans’ surface. In addition, we show that the MP in the micrometer range is transported efficiently around the globe and can penetrate and linger in the stratosphere over time scales of months. The interaction of these particles with the chemistry and physics of the atmosphere is still mostly unknown and deserves to be further investigated.

Organisation(s)
Department of Meteorology and Geophysics
External organisation(s)
University of Vienna
Journal
Environmental Science & Technology
Volume
58
Pages
14338-14347
No. of pages
10
ISSN
0013-936X
DOI
https://doi.org/10.1021/acs.est.4c03216
Publication date
07-2024
Peer reviewed
Yes
Austrian Fields of Science 2012
105208 Atmospheric chemistry
Keywords
ASJC Scopus subject areas
General Environmental Science, General Chemistry, Environmental Chemistry
Portal url
https://ucrisportal.univie.ac.at/en/publications/9cd998c8-0a89-4bf5-83e2-18b011e3a4e6