Geoscience Reference
In-Depth Information
Chapter 18
IceCoreArchivesofMineralDust
Paul Vallelonga and Anders Svensson
Abstract The ice caps of Greenland and Antarctica provide an archive of dust
deposition covering several glacial-interglacial climate cycles. Greenland ice core
records extend back to approximately 130 ka ago, showing great changes in dust
concentrations from interglacial (45 ng/g) to glacial (5,000 ng/g) climate periods.
Strontium and Neodymium isotopic fingerprinting indicate that the Gobi and
Taklamakan Deserts in central Asia are the predominant source of dust deposited in
Greenland. Antarctic ice core records archive the past 8 glacial-interglacial cycles,
with less dust deposited during interglacial (15 ng/g) and glacial (800 ng/g) climate
periods in comparison to Greenland. Loess fields and glacial outwash plains in
southern South America are the main sources of dust deposited in Antarctica,
although there is evidence of other sources, such as Australia and local dust
deflation zones in Antarctica, also contributing dust during interglacial periods.
Dust concentrations in ice cores provide a detailed record of the manner in which
climate variability influences the combined processes of dust deflation, transport
and deposition processes, but the precise distinction of drivers and feedbacks within
these processes remains an ongoing challenge.
Keywords Greenland ￿ Antarctica ￿ Dust ￿ Provenance ￿ Strontium isotope ￿
Particle size distribution
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