Oceanic efflux of ancient marine dissolved organic carbon in primary marine aerosol.

Breaking waves produce bubble plumes that burst at the sea surface, injecting primary marine aerosol (PMA) highly enriched with marine organic carbon (OC) into the atmosphere. It is widely assumed that this OC is modern, produced by present-day biological activity, even though nearly all marine OC is thousands of years old, produced by biological activity long ago. We used natural abundance radiocarbon (C) measurements to show that 19 to 40% of the OC associated with freshly produced PMA was refractory dissolved OC (RDOC).

Properties of Seawater Surfactants Associated with Primary Marine Aerosol Particles Produced by Bursting Bubbles at a Model Air-Sea Interface.

Surfactants account for minor fractions of total organic carbon in the ocean but can significantly influence the production of primary marine aerosol particles (PMA) at the sea surface via modulation of bubble surface tension. During September and October 2016, model PMA (mPMA) were produced from seawater by bursting bubbles at two biologically productive and two oligotrophic stations in the western North Atlantic Ocean. Total concentrations of surfactants extracted from mPMA and seawater were quantified and characterized via measurements of surface tension isotherms and critical micelle concentrations (CMCs).