Modeling microplastic selectivity and enhancement in small sea spray aerosols

Recent field studies have suggested that the ocean may be a source as well as a sink for micro- and nanoplastics through emissions in sea spray aerosols. Bursting bubbles are known to transport large quantities of particles, such as bacteria and sea salt, into the atmosphere. This effect is enhanced when hydrophobic particles are scavenged on the bubbles, producing highly enriched droplets. However, estimates of plastic transport via this pathway have large uncertainties due to limited size detection techniques in field studies and relatively few laboratory studies. Here we combine various physical models to provide some guiding principles. These new insights reveal the dominance of jet drops in particle transport via bursting bubbles and highlight the strong size-dependence of droplet enrichment, expanding our understanding of the complex fate and transport dynamics of micro and nanoparticulates in the ocean.