@article{fdi:010050709,
  title = {{C}haracterization of iron oxides in mineral dust aerosols : implications for light absorption (art. no. {D}21207)},
  author = {{L}afon, {S}. and {S}okolik, {I}.{N}. and {R}ajot, {J}ean-{L}ouis and {C}aquineau, {S}andrine and {G}audichet, {A}.},
  editor = {},
  language = {{ENG}},
  abstract = {{W}e report on measurements that were specifically designed to determine iron oxides in mineral dust aerosols needed for improved optical modeling. {A}tmospheric dust samples as well as samples generated in a wind tunnel from soils were analyzed by a number of analytical techniques for their total and free iron content ( bulk and size resolved), hematite and goethite, mineralogy, and size distribution. {T}hese samples are representative of several important dust sources in {E}ast {A}sia and northern {A}frica. {A} novel data set generated from these measurements enables us to perform an in- depth modeling study of dust optical properties in the solar spectrum. {W}e modeled the iron oxide - clay aggregates, which are the key light- absorbing species, as well as their mixtures with nonabsorbing minerals. {A} volume fraction of iron oxide in aggregates was determined from measurements. {S}ignificant differences in the single- scattering albedo, omega(0), were found between hematite- and goethite- clay aggregates, although these calculations involved several important assumptions about the partition of hematite and goethite in size- resolved aggregates. {F}urthermore, we found that variability of the free iron content is large enough to cause important differences in omega(0) of mineral dust originating from different sources. {I}n contrast, this variability has little effect on the extinction coefficient and optical depth. {W}e demonstrate that for the same size distribution, omega(0) calculated from data obtained for {C}hinese and {T}unisian samples show higher values and more distinct wavelength dependence than those of {N}iger dust. {A}ll the above omega(0) differ from ones calculated using the refractive indices of {P}atterson et al. ( 1977) or the {OPAC} model ( {H}ess et al., 1998), which are often used in radiative transfer studies. {W}e conclude that information on a size- resolved content of free iron and a fraction of hematite and goethite in aggregates will need to be known on a regional basis to improve the prediction of the single- scattering albedo at solar wavelengths and hence the radiative impact of atmospheric mineral dust.},
  keywords = {},
  booktitle = {},
  journal = {{J}ournal of {G}eophysical {R}esearch {A}tmospheres},
  volume = {111},
  numero = {{D}21},
  pages = {{NIL}_62--{NIL}_80},
  ISSN = {0148-0227},
  year = {2006},
  DOI = {10.1029/2005{JD}007016},
  URL = {https://www.documentation.ird.fr/hor/fdi:010050709},
}