Phytoplankton Take Flight: Airborne Dispersal via Large Marine Aerosols

Large sea spray aerosol particles are often assumed to quickly fall back to the ocean surface and are thus generally overlooked. However, new research shows that large aerosol (up to 90 µm) may be more prevalent in the lower atmosphere than commonly applied parameterisations suggest, and that these aerosols may carry intact phytoplankton cells. Writing in Environmental Science & Technology, the authors report frequent aerosol larger than 20 µm observed during moderate wind and wave conditions, and show direct airborne observations of intact phytoplankton cells contained within these aerosols, including small flagellates, diatoms, and colonial organisms. Using two months of field measurements combining aerosol sizing, microscopy, and environmental monitoring, the study highlights the frequent presence of large biological aerosols under low wind and wave conditions. These findings reveal a potential atmospheric dispersal route for phytoplankton and suggest that large marine aerosols play a broader role in connecting ocean and atmosphere, ecosystems, and climate than previously recognised.

Reference: Sinnett, G., Lenain, L., Braham, E., et al. (2025). Contribution of large marine aerosols in phytoplankton dispersal. Environ. Sci. Technol., 59(14): 7348–7356. https://doi.org/10.1021/acs.est.4c14473