CAREER: Air-sea Exchange of Volatile Organic Compounds--Impacts on Climate and Atmospheric Chemistry

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Biogenic volatile organic compounds (BVOC), emitted from photosynthetic organisms, play a controlling role in both regulating oxidant loadings and setting the production rate of secondary organic aerosol (SOA) in both terrestrial and marine environments. To date, the vast majority of research has focused on terrestrial sources of BVOC, with specific attention to the factors that control the emission rates of isoprene, monoterpenes, and sesquiterpenes. In comparison, considerably less is known about marine BVOC emissions. Similar to terrestrial processes, the spatio-temporal distribution of marine BVOC emissions is thought to be highly variable, depending on the number concentration and species of photosynthetic organism. It has been suggested that marine BVOC emissions in highly productive regions of the oceans: 1) impact oxidant loadings in the marine boundary layer (MBL), 2) contribute to SOA production, and 3) alter particle size and microphysical properties, thus impacting cloud formation and persistence in the MBL. At present, there exists an extreme paucity of experimental data of BVOC fluxes to constrain global models of ocean BVOC emissions and their subsequent impact on climate and atmospheric chemistry. This multi-scale investigation is designed to link detailed laboratory investigations of isoprene and total monoterpene production from isolated monocultures of an array of relevant marine organisms with direct measurements of isoprene and total monoterpene emissions made via eddy correlation during coastal algae blooms from the Scripps Institution of Oceanography (SIO) pier and during a research cruise in a region of high biological activity and high wind speeds.The educational component of the effort involves coupling with the Birch Aquarium, the educational outreach center of SIO, and their Summer Learning Adventure Camp programs to: 1) Develop a hands-on experiment, for students in 7-9th grade, to investigate the uptake of carbon dioxide by the ocean and its impact on ocean acidity. The lesson will discuss fundamental scientific concepts (e.g., solubility, acid-base chemistry), while investigating how the atmosphere and oceans are linked. Further, the experiment will be designed with the intent of teaching students the scientific process in which hypotheses are designed and tested. 2) Connect graduate students, who have designed miniature carbon dioxide sensors as part of an existing analytical chemistry graduate class, with 7-9th grade students who will then use these sensors in their hands-on experiment. 3) Engage 7-9th grade students as they discover active research alongside graduate student guides and participate in hands-on experiments. Students will make observations, collect data, and learn about a variety of scientific instruments and their applications.