Organic Aerosol

Our interests in aerosol organic matter is two-fold. First we wish to develop a more detailed understanding of the oxidation mechanisms of volatile organic compounds and their coupling to gas-particle partitioning in order to better predict the sources of secondary organic aerosol (SOA). Second, organic matter is likely a mixture of compounds that span a spectrum in chemical and physical properties which ultimately affect the impacts of aerosol particles on heterogeneous chemistry, radiation, and clouds. Towards the first interest our efforts to date have involved studying the heterogeneous oxidation processes of aerosol organic matter and developing new analytical methods for studying organic aerosol composition on the molecular level using chemical ionization high resolution time of flight mass spectrometry (CI-HR-TOFMS). This latter work has been performed in collaboration with Aerodyne, Inc, UCSD, and Tofwerk with funding through a DOE grant to ARI and an NSF CAREER award to J. Thornton.  Towards the second interest, we have studied how organic films on aqueous aerosol particles affect mass transfer and heterogeneous reaction rates via both laboratory and field studies, as well as how organic coatings affect heterogeneous ice nucleation. This latter project has been collaboration with Dan Cziczo (now at MIT) and Dr. Kulkarni of Pacific Northwest National Laboratory with funding from PNNL/DOE.
Further, recent examples of the Thornton group’s efforts in this field are our participation in the BAECC (2014), SOAFFEE (2015) and HI-SCALE (2016) campaigns and the OXFLUX project.