Research Projects

Particles less than one micron in diameter have serious adverse impacts on human health and play an important role in climate forcing, visibility degradation, and deposition to ecosystems and crops. Organic aerosols (OA) form a significant fraction of submicron aerosols and typically comprise between 30 - 80% of the mass fraction. Nevertheless, the sources and composition of submicron OA in California remain highly uncertain. The objective of the proposed research is to provide an improved characterization of the sources and atmospheric processing of OAs in the Sacramento and foothills region. Specifically, advanced analyses will be carried out on data collected with a high resolution, time of flight, aerosol mass spectrometer (HR-ToF-AMS) and other instruments during the DOE-funded Carbonaceous Aerosols and Radiative Effects Study (CARES). The proposed research will provide information on source strengths of primary organic aerosols (POA), mechanisms leading to secondary organic aerosol (SOA) formation, and photochemical processing of organic aerosols and gaseous organic precursors in Northern California. The resulting data will lead to improvements in regional air quality models used to predict the efficacy of various emissions control programs.