Research funded by CPO’s Atmospheric Chemistry, Carbon Cycle, and Climate (AC4) program was published in Nature Geosciences. The article – “Contribution of sea surface carbon pool to organic matter enrichment in sea spray aerosol” – assesses the relationship between the organic carbon content of sea water and freshly emitted sea spray aerosol in the North Atlantic as well as the coastal waters of California.
Breaking waves on the ocean surface generate air bubble that scavenge organic matter from the surrounding sea water. When injected into the atmosphere, these bubbles burst to yield sea spray aerosols enriched in organic matter, relative to sea water. When downwind of plankton blooms, the organic carbon content of sea spray aerosol is weakly correlated with satellite-derived measurements of chlorophyll a levels, a measure of phytoplankton biomass.
In this study, the scientists assessed the relationship between the organic carbon content of sea water and freshly emitted sea spray aerosol in the presence and absence of plankton blooms in the North Atlantic Ocean and the coastal waters of California.
According to the study, the organic carbon content of freshly emitted sea spray aerosol was similar in all regions sampled, despite significant differences in seawater chlorophyll a levels. The proportion of freshly emitted aerosols that served as cloud condensation nuclei at a given supersaturation was also similar across sampling sites. The large reservoir of organic carbon in surface sea water remained relatively constant across the regions sampled, and independent of variations in chlorophyll a concentrations.
In their report, the scientists suggested that this reservoir is responsible for the organic carbon enrichment of freshly emitted sea spray aerosol, overwhelming any influence of local biological activity as measured by chlorophyll a levels.
To view the full article, visit: http://www.nature.com/ngeo/