AOS Faculty Profile
My research focuses on the chemistry of the atmosphere. I study the effects of anthropogenic and natural emissions, chemical processing, and atmospheric transport on the distributions of pollutants in the atmosphere, on regional air quality, and on intercontinental transport of pollution. In particular, my work focuses on tropospheric ozone and aerosols (particles). These species, besides being important for air quality, also have significant effects on Earth's climate. Historical changes in anthropogenic emissions have dramatically increased atmospheric concentrations of ozone and aerosols.
The primary tools I use in my research are computer models of chemistry and climate. I develop models to represent the chemistry of the atmosphere, and interactions between chemistry and climate. Use of such models in combination with observations of key species helps us to improve our understanding of the factors controlling pollutant concentrations in the atmosphere, project how those concentrations may change in the future, and estimate how those changes may affect climate.
Some Recent Publications:
Fang, Y., A.M. Fiore, L.W. Horowitz, A. Gnanadesikan, H. Levy, Y. Hu, and A.G. Russell, Estimating the contribution of strong daily export events to total pollutant export from the United States in summer, J. Geophys. Res., 114, D23302, doi:10.1029/2008JD010946, 2009.
Fiore, A., J. West, L. Horowitz, V. Naik, and M.D. Schwarzkopf, Characterizing the tropospheric ozone response to methane emission controls and the benefits to climate and air quality, J. Geophys. Res., 113, D08307, doi:10.1029/2007JD009162, 2008.
United States Climate Change Science Program (CCSP), Climate Projections Based on Emissions Scenarios for Long-Lived and Short-Lived Radiatively Active Gases and Aerosols. A Report by the U.S. Climate Change Science Program and the Subcommittee on Global Change Research. H. Levy II, D.T. Shindell, A. Gilliland, M.D. Schwarzkopf, L.W. Horowitz, (eds.). Department of Commerce, NOAAs National Climatic Data Center, Washington, D.C., USA, 100 pp., 2008.
Horowitz, L.W., A.M. Fiore, G.P. Milly, R.C. Cohen, A. Perring, P.J. Wooldridge, P.G. Hess, L.K. Emmons, and J.-F. Lamarque, Observational constraints on the chemistry of isoprene nitrates over the eastern United States, J. Geophys. Res., 112, D12S08, doi:10.1029/2006JD007747, 2007.
Horowitz, L.W., Past, present, and future concentrations of tropospheric ozone and aerosols: Methodology, ozone evaluation, and sensitivity to aerosol wet removal, J. Geophys. Res., 111, D22211, doi:10.1029/2005JD006937, 2006.