Simplified analytic model to estimate the Ångstrom exponent in a Junge aerosol size distribution

Abstract

In this study, the analytic type of a simplified model to estimate the Ångstrom exponent was developed. The relation between aerosol size distribution with different refractive indices and the Ångstrom exponent was analytically obtained using an assumption of Junge aerosol size distribution. Polynomial and harmonic mean-type approximations were applied for parameterizations of the extinction coefficient and the Ångstrom exponent. Results obtained from the simplified model were compared with numerical solutions and showed comparable results. Polynomial approximations produced more accurate results than harmonic mean approximations. This study also showed how the Ångstrom exponent changes for a Junge aerosol size distribution with different refractive index using the simplified analytic model. © 2010, Mary Ann Liebert, Inc.