Distinguished Lecture Series: Dr. Barbara Finlayson-Pitts
Particle Formation from Sulfur Compounds in a Coastal Urban Area: Now and Then
Abstract: While some airborne particles arise from direct emissions, under many circumstances they are formed in air from reactions of gas phase precursors. A well-known example is the formation of sulfuric acid and sulfate particles from the oxidation of SO2 emitted during combustion of sulfur-containing fossil fuels. The oxidation of organosulfur compounds, which have a variety of natural and anthropogenic sources, is another way to form SO2 and sulfate particles. However, this chemistry also forms methanesulfonic acid (MSA), which we have shown also forms particles in the presence of amines, with water vapor playing a key role. In a coastal urban area such as the South Coast Air Basin (SoCAB) of southern California, there are both fossil fuel sources of SO2 and many different sources of organosulfur compounds, both of which contribute to particle formation in air. An integrated approach of laboratory experiments, quantum chemical theory, field measurements and airshed modeling is shown to provide useful insights into the potential relative contributions of these processes to particle formation in the SoCAB under current conditions and in a future scenario with sulfur removed from fossil fuels. The results may be particularly relevant to understanding the contributions of some agricultural activities to airborne particles.
Bio: Barbara Finlayson-Pitts is Professor of Chemistry at the University of California, Irvine, UCI Distinguished Professor and Director of AirUCI. She did her undergraduate degree at Trent University in Canada, and her M.S. and Ph.D. at U.C. Riverside. She joined the faculty in the Department of Chemistry and Biochemistry at Cal State Fullerton in 1974, and in 1994 moved to UC Irvine. Her research focuses on experimental studies of reactions that occur in the atmosphere, particularly those that form and grow particles and those that occur on surfaces. Professor Finlayson-Pitts is author or coauthor of more than 180 scientific publications and two books on atmospheric chemistry. She has mentored many students from undergraduates to graduate students, as well as postdoctoral fellows who have gone on to pursue a wide variety of careers. Professor Finlayson-Pitts' research and teaching has been recognized by a number of awards, including the 2004 American Chemistry Society Award for Creative Advances in Environmental Science & Technology, election as a Fellow of the American Association for the Advancement of Science, the American Geophysical Union and the Royal Society of Chemistry, the American Academy of Arts & Sciences and the National Academy of Sciences. She received the Coalition for Clean Air Carl Moyer Award for Scientific Leadership and Technical Excellence and the Haagen-Smit Clean Air Award from the California Air Resources Board.