Mineral Dust and its Microphysical Interactions with Clouds - Mineral Dust: A Key Player in the Earth System - page 302

Table 12.2 (continued)

Experiment Major findings Reference

Impact of generation
method on measured
hygroscopicity

Particles from atomization of
aqueous solutions displayed
hygroscopicities 100 times
greater than the ones obtained
for dry-generated calcite
mineral dust particles. Using
wet-generation methods to
suspend mineral dust will not
produce particles with the
correct physicochemical
properties in laboratory studies

Sullivan et al. ( 2010a , b )

Novel method to produce
calcite

Calcite produced by spraying
Ca(HCO 3 ) 2 solution in a tube
furnace. Dried Ca(HCO 3 ) 2
particles were somewhat more
hygroscopic than calcite, but
during humidification a
restructuring takes place and
2/3 is transformed to calcite

Zhao et al. ( 2010 )

CCN activity and droplet
activation kinetics of
fresh unprocessed
regional dust samples

Dust aerosols are CCN at
atmospherically relevant
supersaturations, with dry
diameters much larger than
pure salt. The CCN activity is
controlled by the adsorption of
water onto the clay and the
mineral components in the
samples

Kumar et al. ( 2011a )

CCN activity and size
distribution of wet
processed regional
dust samples

Wet-generated clays and minerals
produce a bimodal size
distribution with the CCN
activity of the smaller mode
following the Köhler approach
(KA), while the larger mode
which is less hygrophilic
follows the water adsorption
approach. Wet-generated
regional dust samples, on the
other hand, produced unimodal
size distributions with small
particle sizes, CCN activation
consistent with the KA, and
exhibit hygroscopicity similar
to inorganic salts

Kumar et al. ( 2011b )

(continued)