HR: 17:10h
AN: A44B-04 INVITED     [Abstracts]
TI: Secondary Organic Aerosol Production From Terpenes: Chemical Influences on Aerosol Yields
AU: * Donahue, N M
EM: nmd@andrew.cmu.edu
AF: Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, PA 15213 United States
AU: Huff-Hartz, K
EM: karah@andrew.cmu.edu
AF: Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, PA 15213 United States
AU: Presto, A A
EM: apresto@andrew.cmu.edu
AF: Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, PA 15213 United States
AU: Pathak, R
EM: rpp@andrew.cmu.edu
AF: Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, PA 15213 United States
AU: Robinson, A L
EM: alr@andrew.cmu.edu
AF: Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, PA 15213 United States
AU: Pandis, S N
EM: spyros@andrew.cmu.edu
AF: Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, PA 15213 United States
AB: Secondary Organic Aerosol (SOA) generation is caused by the production of relatively low vapor pressure products from higher vapor pressure precursors. Mono- and sesquiterpenes are recognized as major sources of biogenic SOA, especially following ozonolysis. SOA yields, however, depend on numerous factors. First is the widely accepted work of Pankow, Odom, and colleagues demonstrating that the partitioning of semi-volatile compounds depends strongly on the total mass of organic aerosol in a given system; extension of this theory leads us to refute the 'fallacy of the polluting tree'. Biogenic SOA yields in the absence of primary and secondary anthropogenic aerosol would be significantly lower than in polluted urban and regional environments. Other factors strongly influence SOA production. While the reaction mechanism following ozonolysis remains poorly defined, we have recently shown that SOA yields decline dramatically under high NOx conditions. However, continued oxidation, or aging, of semi-volatile organics in either phase will tend to further lower product vapor pressures, thus increasing aerosol yields. In addition to recent experimental results addressing all of these issues, we shall present a unifying framework for modeling semi-volatile partitioning and aerosol aging.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0315 Biosphere/atmosphere interactions (0426, 1610)
DE: 0317 Chemical kinetic and photochemical properties
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005