Emission, atmospheric transport and deposition of microplastics – ATMO-PLASTIC
Emission, atmospheric transport and deposition of microplastics
Microplastics (MP) are an emerging contaminant, with significant MP found from Oceans to remote terrestrial locations and potential (in)direct effects on ecosystem health. The quantity of MP polluting the terrestrial environment is unknown, with knowledge gaps in the global MP mass balance and understanding how MP are transported to terrestrial ecosystems. The ATMO-PLASTIC project will therefore investigate the role of the atmosphere in global MP cycling.
Quantify past and ongoing atmospheric MP abundance, transport and deposition
Preliminary studies on MP in the atmosphere, in wet deposition (rain and snowfall) and in soils indicate that the atmosphere may play an important role in disseminating MP across the globe, including to remote areas such as the Arctic. The ATMO-PLASTIC project’s main objective is to fill this knowledge gap in what is known about atmospheric MPs by systematically quantifying the global extent of MPs and the factors that control atmospheric MP abundances. We will analyze aerosol samples from 9 global sites, and 4 oceanographic expeditions. We recently showed that wind-driven sea spray formation is a likely marine MP source to both long-range marine and terrestrial MP transport. Here we also hypothesize that urban-industrial-agricultural activities are terrestrial MP emission hotspots and we will further investigate and estimate these emission sources. Furthermore, by analyzing natural peat archives of atmospheric deposition in both southern and northern hemispheres, we intend to broadly characterize the timing and extent of past MP deposition and emission.
The ATMO-PLASTIC project takes advantage of the unique opportunity to study existing (archived) global aerosol filters and (partly archived) age-dated peat cores to fill critical knowledge gaps in the role of the atmosphere within the global plastics/MP cycles. Through collaboration and support from the ANR INHALE project, the GEOTRACES programme, and the EcoLab peat archive, a unique and extensive sample set is accessible to the ATMO-PLASTIC project. We will quantify and characterise MP in aerosols from 9 key land-based atmospheric observatories. The sites were selected to cover global, remote environments in the planetary (marine, polar and continental) boundary layer and free troposphere. The terrestrial atmospheric samples will be complemented by marine aerosols collected during the GEOTRACES Eastern Tropical Pacific (GP16 cruise), North Atlantic (GA03), Arctic (GN01), and Pacific Gyre (GP015) cruises. GP03 and GP15/16 are targeted because they specifically transect marine MP gyres, while GN01 targets the remote Arctic Ocean, characterized by abundant terrestrial matter inputs from rivers and atmosphere (wildfires, dust). Oceanic gyres are large-scale circular currents where plastics and other marine debris tends to concentrate. To understand past atmospheric MP deposition and abundance we weill use an extensive international ombrotrophic peat repository, stored at -20C at EcoLab (Toulouse). Analysis of peat archives adjacent to the atmospheric sampling locations will provide a temporal trend to place current-day MP atmospheric pollution within the historical context from pre-plastic pollution times to present day (< 1950 to 2020). MP metrology and MP characterisation relies on clean lab facilities, and proven filtration, density separation, digestion and pre-concentration methods, followed by FTIR and Raman microscopy for MP identification and quantification.
The expected results will be Open Access data on:
- global atmospheric MP abundance over land and oceans
- estimates of marine and terrestrial MP emissions
- estimates of past atmospheric MP deposition over land
ATMO-PLASTIC project data will be crucial in calibrating atmospheric transport models of global MP emission, transport and deposition. Such models are necessary to estimate the global impact of MP on ecosystem and human health.
soon
Microplastics (MP) are an emerging contaminant, with significant MP found in oceans and remote terrestrial locations and direct and indirect effects on ecosystem and human health. The quantity of MP polluting the terrestrial environment is unknown, with knowledge gaps in the global MP mass balance. Based on our recent findings, the ATMO-PLASTIC project hypothesizes an important role for the atmosphere in MP cycling, and aims to illustrate atmospheric MP occurrence and transport on a global scale. We will examine a global bank of marine and terrestrial aerosol filters and peat cores to quantify the spatio-temporal variation of global atmospheric MP pollution. Aerosol and peat MP analysis will illustrate the terrestrial and marine MP emission sources and define the temporal trends in atmospheric MP pollution. We will use langrangian and box models for atmospheric source appointment and global MP mass balance closure, and forecasting of global MP dissimination through Earth surface reservoirs during the 21st century.
Project coordination
Jeroen SONKE (Géosciences Environnement Toulouse)
The author of this summary is the project coordinator, who is responsible for the content of this summary. The ANR declines any responsibility as for its contents.
Partnership
GET Géosciences Environnement Toulouse
UGA-IGE Institut des Géosciences de l'Environnement
ECOLAB LABORATOIRE ECOLOGIE FONCTIONNELLE ET ENVIRONNEMENT
Help of the ANR 651,544 euros
Beginning and duration of the scientific project:
December 2020
- 48 Months
