PARENT SESSION
PW16 - Atmopheric Fate Processes
Wednesday, 20 November 2002
8:00 AM to 6:30 PM
Exhibit Hall
(P894) Organic and elemental carbon concentrations on PM2.5 aerosols in New Jersey air.
Gioia, Rosalinda*,1, Offenberg, John1, Gigliotti, Cari1, Eisenreich, Steven1,2, 1 Rutgers University, New Brunswick, New Jersey, USA2 Joint Research Center: Institute for Environment and Sustainability, Ispra, Varese, Italy
ABSTRACT- The proportion of total organic carbon (OC) derived from primary versus secondary aerosol formation cannot be measured directly. However, it is important to know the origin of particles to aid in the identification of sources. Since OC and elemental carbon (EC) from primary formation often have the same sources, EC is used as a tracer of primary organic carbon. The concentrations of OC and EC associated with PM2.5 measured as part of the New Jersey Atmospheric Deposition Network (NJADN), have been quantified by a thermal-optical method. The samples are representative of four different geographical land-uses: the suburban New Brunswick site, the Sandy Hook coastal/marine area, the Jersey City and Camden urban sites, and the rural/forested Pinelands. The average OC and EC concentrations follow the degree of urbanization/industrialization with highest concentrations occurring at the urban/industrial Liberty Science Center (Jersey City) and Camden sites. There is a statistically significant difference between OC and EC concentrations on a diurnal scale (on average, OC is higher at night) and on a season scale (with highest concentrations in the colder seasons, winter and fall). The data show that the majority of total organic carbon is derived from primary formation and although secondary organic aerosol formation does occur, it is the primary organic aerosols that dominate.
Key words: organic carbon, elemental carbon, New Jersey, primary/secondary formation