Factors influencing the organic carbon content of marine aerosols: A laboratory study

Abstract

Summary and entire article are available on microfiche. Order from American Geophysical Union, 1909 K Street, N. W., Washington, D. C. 20006. Document J76‐004; $1.00. Payment must accompany order. A series of laboratory experiments using natural seawater were conducted to examine several factors which influence the organic carbon(OC) content of marine atmospheric sea‐salt particles produced by bursting bubbles at the air‐sea interface. The organic carbon/Na ratio of these laboratory‐generated atmospheric sea‐salt particles was found to be dependent on the quantity of organic carbon in the seawater, the nature of the organic compounds in the seawater, the amount of surfactants in the seawater, and the distance the bubbles traveled in seawater before bursting at the air‐seawater interface. The dissolved and/or colloidal fractions of the organic material in the seawater used were primarily responsible for the organic carbon content of the atmospheric particles. Filtration of the seawater did not affect the OC/Na ratio of the aerosols produced. The OC/Na ratio of atmospheric sea‐salt particles generated from Sargasso seawater was 0.008±0.005, while that of particles generated from Narragansett Bay water was 0.093±0.053.

Predicted hygroscopic growth of sea salt aerosol

“…Studies of bubble bursting processes suggest that the formation of surface layers on seawater in which low surface tension species are enhanced may result in higher organic concentrations in the particles that form from bubble bursting [Hoffmann and Duce, 1976]. Laboratory work also suggests that even in well-mixed conditions, high molecular weight species may form particles preferentially during the film-breaking process [Quinn et al, 1975].…”

Global distribution and surface activity of macromolecules in offline simulations of marine organic chemistry

“…As might be expected, structures known to exist inside phytoplanktonic and microbial cells were quickly identified as fresh release forms (Lee and Bada 1977;Gagosian and Stuermer 1977). Organic films were simultaneously documented at the multiple water-air interface types (Garrett 1967;Hoffman and Duce 1976). Analytical techniques demanded by such studies were quite challenging, since diverse functional groups had to be distinguished and/or separated from the heterogeneous ionic medium that is seawater.…”

Marine aerosol production: a review of the current knowledge

“…Blanchard 1964;Hoffman & Duce 1976). Recent field measurements clearly document the presence of organic matter in individual particles (Middlebrook et al 1998) and a relevant contribution of organic species to fine aerosol mass in the unperturbed MBL (Putaud et al 2000).…”