Nanoparticle composition at a rural U.S. forest site: evidence for diverse sources

Wednesday, 17 December 2014
Michael J Lawler, John Victor Ortega and James N Smith, National Center for Atmospheric Research, Boulder, CO, United States
Atmospheric fine particles were chemically analyzed using the Thermal Desorption Chemical Ionization Mass Spectrometer (TDCIMS) as part of the Southern Oxidant and Aerosol Study (SOAS) in Brent, AL, USA during June-July 2013. Sampled particle size distributions ranged from volume mean diameters of ~ 40 to 120 nm. A wide variety of species were observed, including organic acids, aliphatic amines, ammonium, acid anhydrides, sulfate, and cyclic diketones. Potential sources for the various compounds include biomass burning, biogenic emissions, and local industry. A subset of the observed species was enhanced during a new particle formation event, providing clues to the mechanisms driving small particle growth in this environment.