Postdoctoral Fellow, Center for Atmospheric Particle Studies – Carnegie Mellon University, 2008-2012
Ph.D. Environmental Engineering – Georgia Institute of Technology, 2008
M.S. Environmental Engineering – Georgia Institute of Technology, 2006
B.S. Chemistry – University of Florida, 2001
Our research is centered on issues of air pollution and atmospheric chemistry. A main goal of our work is to understand the sources, transformation, and fate of pollutants in the atmosphere. Our research focuses on a class of pollutants known as particulate matter (PM) or aerosols. These small particles in the air have detrimental impacts on human health and important implications for climate change. Some particles are emitted directly (think tailpipe emissions) into the atmosphere while others form from chemical reactions of gas-phase compounds: our work aims to better understand these formation processes.
Our research is carried out through a combination of atmospheric measurements, laboratory experimentation, and modeling work. We develop and deploy instrumentation to measure in situ aerosol loadings at high time resolution in order to investigate and explain the factors that influence their concentrations in the atmosphere. Based on our atmospheric observations, we also conduct laboratory experiments to characterize specific chemical mechanisms and processes that may be important for aerosols. Finally, we utilize models to both assess the large-scale impacts (continental to global scales) of aerosols on health and climate and to probe our understanding of the processes impacting aerosol concentrations through direct comparison with observations.
Hennigan, C. J.; Westervelt, D. M.; Riipinen, I.; Engelhart, G. J.; Lee, T.; Collett, J. L.; Pandis, S. N.; Adams, P. J., Robinson, A. L., New particle formation and growth in biomass burning plumes: an important source of cloud condensation nuclei, Geophysical Research Letters, 39, L09805, doi:10.1029/2012GL050930 (2012).
Engelhart, G. J.; Hennigan, C. J.; Sullivan, A. P.; Miracolo, M. A.; Collett, J. L.; Kreidenweis, S. M.; Robinson, A. L.; Pandis, S. N., CCN Activity of Fresh Primary and Aged Biomass Burning Aerosol, Atmospheric Chemistry and Physics, 12, 7285-7293 (2012).
Hennigan, C. J.; Miracolo, M. A.; Engelhart, G. J.; May, A. A.; Presto, A. P.; Lee, T.; Sullivan, A. P.; McMeeking, G. R.; Coe, H.; Wold, C. E.; Hao, W. M.; Gilman, J. B.; Kuster, W. C.; de Gouw, J.; Schichtel, B. A.; Collett Jr., J. L.; Kreidenweis, S. M.; Robinson, A. L., Chemical and Physical Transformations of Organic Aerosol from the Photo-oxidation of Open Biomass Burning Emissions in an Environmental Chamber, Atmospheric Chemistry and Physics, 11, 7669-7686 (2011).
Hennigan, C. J.; Sullivan, A. P.; Collett Jr., J. L.; Robinson, A. L., Levoglucosan Stability in Biomass Burning Particles Exposed to Hydroxyl Radicals, Geophysical Research Letters, 37, L09806, doi:10.1029/2010GL043088 (2010).
Hennigan, C. J.; Bergin, M. H.; Russell, A. G.; Nenes, A.; Weber, R. J., Gas/particle partitioning of water-soluble organic aerosol in Atlanta, Atmospheric Chemistry and Physics, 9, 3613-3628 (2009).
Hennigan, C. J.; Bergin, M. H.; Weber, R. J., Correlations between water-soluble organic aerosol and water vapor: A synergistic effect from biogenic emissions?, Environmental Science & Technology, 42, 9079-9085 (2008).
Hennigan, C. J.; Bergin, M. H.; Dibb, J. E.; Weber, R. J., Enhanced secondary organic aerosol formation due to water uptake by fine particles, Geophysical Research Letters, 35, L18801, doi:10.1029/2008GL035046 (2008).
Hennigan, C. J.; Sullivan, A. P.; Fountoukis, C. I.; Nenes, A.; Peltier, R. E.; Hecobian, A.; Vargas, O.; Case Hanks, A. T.; Huey, L. G.; Lefer, B. L.; Russell, A. G.; Weber, R. J., On the volatility and production mechanisms of newly formed nitrate and water soluble organic aerosol in Mexico City. Atmospheric Chemistry and Physics, 8, 3761-3768 (2008).
Asa-Awuku, A.; Nenes, A.; Sullivan, A. P.; Hennigan, C. J.; Weber, R. J., Investigation of molar volume and surfactant characteristics of water-soluble organic compounds in biomass burning aerosol, Atmospheric Chemistry and Physics, 8, 799-812 (2008).
Hennigan, C. J.; Sandholm, S.; Kim, S.; Stickel, R. E.; Huey, L. G.; Weber, R. J., Influence of Ohio River valley emissions on fine particle sulfate measured from aircraft over large regions of the eastern United States and Canada during INTEX-NA, Journal of Geophysical Research, 111, D24S04, doi: 10.1029/2006JD007282 (2006).