AAAR 32nd Annual Conference
September 30 - October 4, 2013
Oregon Convention Center
Portland, Oregon, USA
Abstract View
Sources of Black Carbon Condensation Nuclei
Shaokai Gao, Michael Giordano, Daniel Short, Diep Vu, AKUA ASA-AWUKU, University of California, Riverside
Abstract Number: 591 Working Group: Urban Aerosols
Abstract Black Carbonaceous (BC) aerosol is water-insoluble when freshly emitted (~ 1 day) but can add water-soluble materials in surface oxidation and condensation reactions during its atmospheric lifetime. Hence as a BC particle ages, it can modify the overall insoluble fraction, hygroscopic properties, and reduce the critical water-vapor required to initiate heterogeneous nucleation. We review the complex nature of heterogeneous BC nucleation and discuss relevant properties required for droplet formation. BC properties are acquired from ambient measurements, chamber studies, and controlled vehicular studies. A Multi-Angle Absorption Photometer (MAAP) measures BC concentration. Droplet formation potential is characterized with two methods a) with a cloud condensation nuclei counter and b) with the use of a water based condensation particle counter.