Mean shortwave values of the single scattering albedo and the asymmetry parameter of dry atmospheric particles have been measured photometrically. From the single scattering albedo the mean shortwave value of the apparent complex refractive index and the apparent volume fraction of soot within the particulate matter are derived. From 275 measurements the mean value of the single scattering albedo is 0.835, the mean value of the apparent complex refractive index is 1.51–0.026i, and the mean value of the apparent volume fraction of soot is 5.8%. For seventy-seven cases of mostly urban particles the mean value of the asymmetry parameter is 0.39. The term apparent stands for appearing (but not necessarily) real or true. Reasons for this attribute are the idealizations necessary to get a value of the refractive index of atmospheric particles. Consequently the use of an apparent refractive index for modeling purposes is restricted as described in the concluding section.
© 1988 Optical Society of America
Original Manuscript: February 25, 1987
Published: June 1, 1988
Gottfried Hänel, "Single scattering albedo, asymmetry parameter, apparent refractive index, and apparent soot content of dry atmospheric particles," Appl. Opt. 27, 2287-2295 (1988)