Remote aerosol species-identification using IR scattering spectroscopy

摘要

Identification of atmospheric aerosol species and their chemical composition may help to trace their source and better estimate their impact on climate and environment. Optical scattering of aerosols depends primarily on aerosol chemical composition, size distribution, particle shape and the wavelength used. Extraction of features due to the aerosol complex refractive index from scattering spectroscopy at a single angle of observation allows composition identification via the spectral fingerprint, as shown computationally with Mie calculations of the optical scattering. Size-dependent scattering effects are eliminated by using near-forward scattering, such as in the scattering aureole. The only features of the aerosol aureole scattering spectra that very rapidly with wavelength are associated with the composition, so the aureole can give a reliable identification of aerosol composition.