Measurements of black carbon properties during cloud, biomass burning, and free tropospheric conditions at a marine boundary layer site and high elevation mountain site

Black carbon is a subset of the total atmospheric aerosol population that is formed in the incomplete combustion of fossil fuels, biofuels, and biomass. This research focused on the properties of black carbon particles measured in the boundary layer and free troposphere, as well as the activation of black carbon particles by cloud droplets. The primary motivation for this research is to increase our understanding of the properties of black carbon under these different atmospheric conditions. A single particle soot photometer was used to study properties of black carbon particles incorporated into cloud droplets at two field locations: 1) a marine boundary layer site, and 2) a high elevation mountain site. At both sites, a size dependence on the fraction of black carbon incorporated into cloud droplets was observed; and for small (