Composition and major sources of organic compounds of aerosol particulate matter sampled during the ACE‐Asia campaign

Abstract

The organic compound tracers of atmospheric particulate matter, as well as organic carbon (OC) and elemental carbon (EC), have been characterized for samples acquired during the Asian Pacific Regional Aerosol Characterization Experiment (ACE‐Asia) from Gosan, Jeju Island, Korea, from Sapporo, Japan, and from Chichi‐jima Island in the western North Pacific, as well as on the National Oceanic and Atmospheric Administration R/V Ronald H. Brown. Total extracts were analyzed by gas chromatography–mass spectrometry to determine both polar and aliphatic compounds. Total particles, organic matter, and lipid and saccharide compounds were high during the Asian dust episode (early April 2001) compared to levels at other times. The organic matter can be apportioned to seven emission sources and to significant oxidation‐producing secondary products during long‐range transport. Terrestrial natural background compounds are vascular plant wax lipids derived from direct emission and as part of desert sand dust. Fossil fuel utilization is obvious and derives from petroleum product and coal combustion emissions. Saccharides are a major polar (water‐soluble) carbonaceous fraction derived from soil resuspension (agricultural activities). Biomass‐burning smoke is evident in all samples and seasons. It contributes up to 13% of the total compound mass as water‐soluble constituents. Burning of refuse is another source of organic particles. Varying levels of marine‐derived lipids are superimposed during aerosol transport over the ocean. Secondary oxidation products increase with increasing transport distance and time. The ACE‐Asia aerosols are composed not only of desert dust but also of soil dust, smoke from biomass and refuse burning, and emissions from fossil fuel use in urban areas.