MODAL CHARACTER OF ATMOSPHERIC BLACK CARBON SIZE DISTRIBUTIONS

Samples of atmospheric aerosols, collected with cascade impactors in t he urban area of Vienna (Austria) and at a coastal site on the North S ea, were investigated for black carbon (BC) as the main component of a bsorbing material and for mass. The size distributions are structured. The BC distributions of these samples show a predominant mode, the ac cumulation aerosol, in the upper submicron size range, a less distinct finer mode attributable to fresh emissions from combustion sources, a nd a distinct coarse mode of unclear origin. It is important to note t hat some parameters of the accumulation aerosol are related statistica lly, indicating the evolution of the atmospheric accumulation aerosol.