Advanced bulk optical models linking the backscattering and
microphysical properties of mineral dust aerosol
Abstract
Sensitivities of the backscattering properties to microphysical
properties (in particular, size and shape) of mineral dust aerosols are
examined based on TAMUdust2020, a comprehensive single-scattering
property database of irregular aerosol particles. We develop the bulk
mineral dust particle models based on size-resolved particle ensembles
with randomly distorted shapes and spectrally resolved complex
refractive indices, which are constrained with in-situ observations
reported in the literature. The lidar ratio is more sensitive to
particle shape than particle size, while the depolarization ratio is
sensitive to particle size. The simulated bulk backscattering properties
(i.e., the lidar ratio and the depolarization ratio) of typical mineral
dust particles with effective radii of 0.5–3 µm are reasonably
consistent with lidar observations made during several field campaigns.
The dust bulk optical property models are applicable to lidar-based
remote sensing of dust aerosol properties.