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Artificial iron fertilization experiments in the Southern Ocean-a high nutrient, low chlorophyll (HNLC) region of the world oceans-indicate that productivity and subsequent drawdown of carbon dioxide from the atmosphere can be enhanced with increases in bioavailable iron supply. The past record of terrestrial dust flux to the Southern Ocean thus carries potential significance in the context of whether this region was a significant glacial sink for CO2 due to enhanced biological productivity (through iron fertilisation by increased glacial dust fluxes) and lock-up of CO2 in the deep Southern Ocean. Debate exists regarding the presence of dust in Southern Ocean sediments. The supply of detrital minerals to the Southern Ocean has so far been attributed dominantly to glacigenic processes, with glacial erosion of mafic magmatic rocks in distinct source areas, seaward transport of the glacigenic debris by glaciers and ice …