A. Intellectual Merit This project will investigate the fate of organic matter in a cloud/fog system. In particular, we will focus on four defined problems that address the overall issue through field and laboratory observations. First, scavenging efficiencies of particulate organic matter by fogs and clouds will be determined and parameterized based on simple measurable quantities like cloud liquid water content and/or water soluble organic carbon fraction. Second, we will conduct product and kinetic studies to evaluate the potential for reactions within droplets that lead to the formation of secondary organic aerosol matter. We will focus on common volatile organic compounds like Benzene, Toluene, Ethylbenzene and Xylenes (BTEX) that have received less attention than biogenic precursors. Third, we will investigate the homogeneous aqueous phase chemistry of selected organic species, namely, nitrosamines. These can form in clouds during the nighttime. During the day, they are eliminated by cloud photolysis. Both formation and destruction kinetics will be studied in laboratory experiments. The results on BTEX and nitrosamines will be evaluated against field experiments. This includes the partitioning of the target species in the cloud system, as well as, the concentrations of parent and daughter species. Results of the field work will be used to guide laboratory experiments, and identify any gaps in data. Finally, our project will involve multiple, routine cloud measurement sites complemented by intensive, short-term field studies in a variety of environments throughout the United States. This will provide updated information on inorganic cloud chemistry and extend our knowledge of organic matter in clouds and fogs. B. Broader Impact This project will reach out to K-12 students through educational class modules that teach about the formation of clouds and their role in the water cycle, their impact on air pollution and their role in climate processes. This will feature classroom demonstrations adapted to for the appropriate ages. ASU graduate research assistants and the PI will create these modules in cooperation with the Science is Fun program at ASU. This program is a well established program that disseminates instructional modules on a broad range of topics to thousands of children throughout Arizona. A web-interface will allow students and the general public to check on the latest status of our field experiments including real time images from web cameras, movies of cloud events, chemical composition data. Furthermore, undergraduate university institutions will be critical participants in achieving this project's scientific goals. Most of the routine environmental sampling will rely on the cooperation of non-PhD granting institutions at different locales. Students and faculty from these institutions will be crucial to the successful completion of the research goals through field sampling of cloud samples. These undergraduate students will be hosted at ASU to participate in sample analysis through internships. The same options will be made available to ASU undergraduate students, with particular attention given to recruiting through minority outreach programs. Results from the research and outreach activities will benefit the PI's classroom instruction in environmental chemistry: the active involvement of the graduate students in both research and outreach will help train the next generation of teacher-scientists.
|Effective start/end date||9/15/09 → 8/31/14|
- National Science Foundation (NSF): $569,117.00