Abstract

The most visible and potentially harmful components of air pollution haze consist of aerosol particulate matter falling within the 0,1-2-µm diam size range. Conventional chemical analyses of aerosols are suspect, since most atmospheric species are volatile and undergo chemical and physical changes during filter collection. Clearly, schemes such as absorption spectroscopy which allow analysis in the undisturbed aerosol (in situ) are preferable. Unfortunately, Mie light scattering often obscures the minimal particle light absorption, and the aerosol, in general, exhibits complex optical behavior. In addition, background gases, such as H₂O vapor, have wing absorptions that dwarf the particulate contribution at ambient levels.

© 1981 Optical Society of America