www.atmos-chem-phys-discuss.net/11/387/2011/ doi:10.5194/acpd-11-387-2011 © Author(s) 2011. This work is distributed under the Creative Commons Attribution 3.0 License. Organic condensation – a vital link connecting aerosol formation to climate forcing 1Center for Atmospheric Particle Studies (CAPS), Carnegie Mellon University, 15213, Pittsburgh, PA, USA 2Department of Physics, University of Helsinki, 00014, Helsinki, Finland 3Department of Physics and Atmospheric Science, Dalhousie University, B3H 3J5, Halifax, NS, Canada 4Department of Chemistry, University of Toronto, M5S 3H6, Toronto, ON, Canada 5Science and Technology Branch, Environment Canada, M3H 5T4, Toronto, ON, Canada 6Finnish Meteorological Institute, 00880, Helsinki, Finland 7Aerodyne Research Inc., 01821, Billerica, MA, USA 8Department of Chemical Engineering, University of Patras, 26500, Patra, Greece Abstract. Atmospheric aerosol particles influence global climate as well as impair air quality through their effects on atmospheric visibility and human health. Ultrafine (<100 nm) particles often dominate aerosol numbers, and nucleation of atmospheric vapors is an important source of these particles. To have climatic relevance, however, the freshly-nucleated particles need to grow in size. We combine observations from two continental sites (Egbert, Canada and Hyytiälä, Finland) to show that condensation of organic vapors is a crucial factor governing the lifetimes and climatic importance of the smallest atmospheric particles. We demonstrate that state-of-the-science organic gas-particle partitioning models fail to reproduce the observations, and propose a modeling approach that is consistent with the measurements. We demonstrate the large sensitivity of climatic forcing of atmospheric aerosols to these interactions between organic vapors and the smallest atmospheric nanoparticles – highlighting the need for representing this process in global climate models. Discussion Paper (PDF, 4570 KB) Interactive Discussion (Closed, 4 Comments) Final Revised Paper (ACP) Citation: Riipinen, I., Pierce, J. R., Yli-Juuti, T., Nieminen, T., Häkkinen, S., Ehn, M., Junninen, H., Lehtipalo, K., Petäjä, T., Slowik, J., Chang, R., Shantz, N. C., Abbatt, J., Leaitch, W. R., Kerminen, V.-M., Worsnop, D. R., Pandis, S. N., Donahue, N. M., and Kulmala, M.: Organic condensation – a vital link connecting aerosol formation to climate forcing, Atmos. Chem. Phys. Discuss., 11, 387-423, doi:10.5194/acpd-11-387-2011, 2011. Bibtex EndNote Reference Manager XML |