Atmospheric Chemistry Program Seminar

Chemistry of Organic Compounds in the Atmosphere and Indoor Air by Prof. Paul Ziemann, CU Boulder and Recent Results and Upcoming Projects to Investigate Aerosol Sources, Properties, Processes, and Fate by Prof Jose-Luis Jimenez, CU Boulder

Chemistry of Organic Compounds in the Atmosphere and Indoor Air
Prof Paul Ziemann
Abstract:
"Laboratory studies provide much of the fundamental data on reaction kinetics, products, and mechanisms that are needed to understand atmospheric and indoor air chemistry and to develop models that are used to establish air quality regulations and predict the effects of human activities. Research in my laboratory focuses primarily on environmental chamber studies of the atmospheric chemistry of organic compounds emitted from natural and anthropogenic sources and the physical and chemical processes by which oxidized organic reaction products form aerosol particles. In addition to this we have recently conducted a number of studies of indoor air chemistry at CU. In this talk I will describe how we conduct the studies by using a diverse array of measurement techniques."
and
Recent Results and Upcoming Projects to Investigate Aerosol Sources, Properties, Processes, and Fate
Prof Jose-Luis Jimenez
Abstract:
"Organic aerosols (OA) account for about 1/2 of the submicron particle mass in the atmosphere leading to important impacts on climate, human health, and other issues, but their sources, properties, and evolution are poorly understood. In this talk I will present an overview and highlights of research on OA instrumentation, measurements, and modeling by our group over the last year, as well as of upcoming projects of potential interest to 1st year students. Ongoing projects include global aerosol measurements and analysis as part of the NASA ATOM project, which is sampling (almost) pole-to-pole across the vertical profile. Initial model comparisons suggest the importance of fast OA removal channels. We have used an Oxidation Flow Reactor (OFR) at multiple field studies and find consistent patterns, where SOA formation by O3 and NO3 are consistent with models, while formation by OH is substantially underpredicted unless semivolatile and intermediate volatility species are accounted for. We are using the GECKO-A fully explicit model to investigate this underprediction, as well as to characterize the similarities and differences of the chemical regimes across the OFR, large chambers, and the atmosphere. We are investigating gas/particle partitioning in the laboratory for different types of particles. Finally, we are continuing to explore the chemistry of indoor air with ToF-CIMS and other instruments. Future outdoor campaigns may include the study of emissions and chemical evolution of smoke from real fires in the western US (NASA FireChem) with AMS and soft-ionization EESI-TOF. Future indoor campaigns will involve sampling at locations such as dining halls, gyms, and art museums."