Ice Core Archives of Mineral Dust - Mineral Dust: A Key Player in the Earth System - page 470

Fig. 18.7 An example of Greenland ice core dust provenance tracing based on the isotopic
composition of Strontium (Sr) and Neodymium (Nd). Ice core dust is compared to dust from
potential source areas in the Northern Hemisphere. Due to their different geological histories, the
dust source areas have different isotopic fingerprints. A fraction of volcanic ash in the ice core
samples will drag their isotopic signature in the direction of the 'Circum Pacific Volcanic Rocks'.
The ice core dust samples that have been extracted from glacial Greenland ice ( blue dots ) are seen
to have an isotopic composition most similar to a mixing of dust from the Asian source areas.
Modified after (Biscaye et al. 1997 ) and (Svensson et al. 2000 )

as an indication that the dust in Antarctic ice originated from very distant source
locations. Delmonte et al. ( 2002b ) reported particle size distributions in EDC ice
over LGM-Holocene transition, observing a minor shift to larger D v from LGM
(1.90

˙ ˙

0.07 m) to Holocene (2.07 0.24 m) conditions as well as an increase

in dust size variability (LGM g D

˙ D ˙

0.15).
This was interpreted as a change in atmospheric transport patterns from more-
zonal Holocene winds to more-meridional winds during the LGM. More recent
studies (Delmonte et al. 2004b ) have identified opposite trends in deglacial dust
size tendencies, which the authors related to the transport of finer aerosols in the
upper atmosphere and shifts in the location of their subsequent subsidence onto the
Antarctic ice sheet, as described in Sect. 18.3.1.1 .
Despite these observations and the interpretations drawn from them, few studies
have been conducted to unequivocally link ice core records to dust collected in the
Antarctic atmosphere. Fattori et al. ( 2005 ) collected aerosols on stacked filters of
varying porosity (0.4-10 m range) and found a finer mode at coastal Terra Nova
Bay (0.75 m) compared to inland Dome C base (1 m). The Terra Nova Bay
sample had a smaller particle size mode due to the strong influence of fine sea salt

1.60 0.03 and Holocene g 1.80