The freshwater discharge of the Amazon River exerts a significant control on near-surface salinities of the western equatorial Atlantic. The ability to accurately reconstruct past changes in the Amazon River discharge has long been sought, but the lack of regionally-calibrated paleosalinity proxies has limited the success of some previous attempts. In a recent paper published in Biogeosciences, Christoph Häggi and co-authors showed that the stable hydrogen isotopes composition of palmitic acid obtained from suspended matter strongly correlates to stable hydrogen isotopes composition of the water (a proxy for salinity). This new finding raises the possibility of applying the stable hydrogen isotopes composition of palmitic acid from marine sediments to reconstruct past changes in the Amazon River freshwater discharge. Read more clicking here.