International Research Fellowship Program: Atmospheric Implications of the Temperature-and State-dependent Chemistry of Organic Aerosol

Huisman Andrew J, Madison WI

Investigators

Abstract

1006117 Huisman The International Research Fellowship Program enables U.S. scientists and engineers to conduct nine to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad. This award will support a twenty-four-month research fellowship by Dr. Andrew J. Huisman to work with Dr. Thomas Peter at ETH in Zurich, Switzerland. Aerosols (including Secondary Organic Aerosol (SOA)) have been linked to a number of phenomena including climate change and human health effects, and are rightly becoming a priority for the fields of atmospheric chemistry, atmospheric engineering, and climactic modeling. The detailed mechanisms involving Secondary Organic Aerosol are of particular importance as they represent one of the largest factors of uncertainty in climate predictions. This research will contribute directly to our understanding of aerosols and the microscopic processes that drive them. In so doing, it will contribute to understanding and resolving the role of aerosols both in mitigating global warming and in deteriorating air quality. This work may lead to advances in the field of aerosol science that decrease the uncertainty in aerosol processes, providing valuable information to scientists and policy makers on issues from regional air quality to global climate change. The physical state of tropospheric aerosol is still largely unknown despite its importance for cloud formation, atmospheric chemistry, the atmospheric radiation budget, and hence, climate. Among other topics, chemical reactions of organic compounds (which under many conditions represent over half of the aerosol mass) within aerosols are poorly understood, despite their importance to tropospheric chemistry. In general, there is very little information available concerning the interplay of chemistry and physical properties in aerosols. We hypothesize that chemical processing of organic compounds in aerosols will alter aerosol physical properties and that these physical properties may, in turn, influence the extent of chemical processing. These changes may lead to new sinks or sources of atmospherically relevant gases via gas/particle partitioning, as well as altering the lifetime or cloud formation potential of aerosols due to changes in hygroscopic growth. In this work, we investigate these properties to gain information about the total effect that they exert on aerosol processes.