Scattering Phase Functions of Constituents of Mineral Dust Aerosols

Abstract

In this paper, a Mie-based numerical computation and visualization program has been used to compute the phase functions of typical constituents of mineral dust aerosols of Saharan origin in the visible range of the electromagnetic spectrum of wavelength 550nm. Computations were done for scattering angles ranging from 0 to 180 degrees and three radial sizes of 0.25, 0.5 and 1.0 microns. The results show that there is increasing asymmetry and complexity of the phase functions with increasing radial sizes for each of the selected constituents: Illite, Kaolinite, Montmorillonte, Hematite, Calcite and Quartz. The behaviour of these constituents as observed by their phase functions provide information on the optical properties and radiative effects of the mineral dust types and is therefore useful on regional and global scales in assessing radiative impacts of dust outbreak events.

Journal of the Nigerian Association of Mathematical Physics, Volume 20 (March, 2012), pp 331 – 342