On the Importance of Organic Oxygen for Understanding OrganicAerosol Particles

Journal Article · Fri Apr 01 04:00:00 EST 2005 · Aerosol Science and Technology

OSTI ID:878691

Pang, Y; Turpin, B J; Gundel, L A

This study shows how aerosol organic oxygen data could provide new information about organic aerosol mass, aqueous solubility of organic aerosols, formation of secondary organic aerosol (SOA) and the relative contributions of anthropogenic and biogenic sources. For more than two decades atmospheric aerosol organic mass (OM) concentration has been estimated by multiplying the measured carbon content by an assumed (OM)-to-organic carbon (OC) factor, usually 1.4. However, this factor can vary from 1.0 to 2.5 depending on location. This large uncertainty about aerosol organic mass limits our understanding of the influence of organic aerosol on climate, visibility and health. New examination of organic aerosol speciation data shows that the oxygen content is responsible for the observed range in the OM-to-OC factor. When organic oxygen content is excluded, the ratio of non-oxygen organic mass to carbon mass varies very little across different environments (1.12 to 1.14). The non-oxygen-OM-to-OC factor for all studied sites (urban and non-urban) averaged 1.13. The uncertainty becomes an order of magnitude smaller than the uncertainty in the best current estimates of organic mass to organic carbon ratios (1.6 {+-} 0.2 for urban and 2.1 {+-} 0.2 for non-urban areas). This analysis suggests that, when aerosol organic oxygen data become available, organic aerosol mass can be quite accurately estimated using just OC and organic oxygen (OO) without the need to know whether the aerosol is fresh or aged. In addition, aerosol organic oxygen data will aid prediction of water solubility since compounds with OO-to-OC higher than 0.4 have water solubilities higher than 1 g per 100 g water.

• Research Organization: Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
• Sponsoring Organization: USDOE, Small business Technology Transfer Research Phase 1Award Grant DE-FG02-03ER86168. Sunset Laboratory
• DOE Contract Number: AC02-05CH11231
• OSTI ID: 878691
• Report Number(s): LBNL--57273
• Journal Information: Aerosol Science and Technology, Journal Name: Aerosol Science and Technology Journal Issue: 2 Vol. 40; ISSN 0278-6826; ISSN ASTYDQ
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
AEROSOLS
CARBON
FORECASTING
OXYGEN
SOLUBILITY
VISIBILITY
WATER