Low-Temperature Flow Tube Studies of Secondary Organic Aerosol Formation

MATTHEW GOSS, Frank Keutsch, Harvard University

     Abstract Number: 405
     Working Group: Aerosol Chemistry

Abstract
Most laboratory studies of organic aerosol are performed at room temperature, yet much of the atmosphere features lower temperature conditions. For example, secondary organic aerosol (SOA) may form during winter or due to the reactions of lofted reactive VOCs (e.g., from a wildfire event) in the free or upper troposphere. Such conditions affect aerosol formation and properties, for example changing chemical kinetics, aerosol viscosity, and uptake rates. Using a chilled aerosol flow tube, this work examines SOA formation and aging processes across a range of representative temperatures for a series of VOCs relevant to biomass burning emissions, including those typically thought to be too volatile to contribute to aerosol formation. Using chemical ionization mass spectrometry, this work explores trends in both aerosol yield and composition as a function of temperature and evaluates these measurements in the context of SOA modeling methods in chemical transport models.