Reconstruction of the Amazon Basin effective moisture availability over the past 14,000 years

Quantifying the moisture history of the Amazon Basin is essential for under standing the cause of rain forest diversity and its potential as a methane source. We reconstructed the Amazon River outflow history for the past 14,0 00 years to provide a moisture budget for the river drainage basin. The oxy gen isotopic composition of planktonic foraminifera recovered from a marine sediment core in a region of Amazon River discharge shows that the Amazon Basin was extremely dry during the Younger Dryas, with the discharge reduce d by at least 40% as compared with that of today. After the Younger Dryas, a meltwater-driven discharge event was followed by a steady increase in the Amazon Basin effective moisture throughout the Holocene.