Ice core archives of mineral dust

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.