Dust supply factor in climate change

摘要

Dust plays a central role in ocean biogeochemical cycles by supplying iron and other micronutrients to regions were marine productivity is nutrient-limited. Martinez-Garcia et al. present a marine record of dust and iron supply to the Southern Ocean during the past four million years. The data, derived from leaf waxes, establish that previous records of dust flux from Antarctic ice cores are broadly representative of a larger area. Importantly, the dust and iron supply rose sharply 1.25 million years ago, suggesting that increased dust supply may be a major influence on the more severe swings between glacial and interglacial climate of the late Pleistocene.