Publication Date:
2019-07-11
Description:
We investigate the possibility that the refractory, infrared-light-absorbing carbon particulate material known as tar balls or tar brown carbon (tar brC) generates a unique signal in the scattering and incandescent detectors of the single particle soot photometer (SP2). As recent studies have defined tar brC in different ways, we begin by reviewing the literature and proposing a material-based definition of tar. We then show that tar brC results in unique SP2 signals due to a combination of complete or partial evaporation, with no or very little incandescence. Approximately 70 % of tar particles incandesced. At the time of incandescence the ratio of light scattering to incandescence from these particles was up to twofold greater than from soot black carbon (BC). In our sample, where the mass of tar was threefold greater than the mass of soot, this led to a bias of
Electronic ISSN:
1680-7375
Topics:
Geosciences