Progress in paleosalinity: Overview and presentation of a new approach

This paper concerns the use of stable oxygen isotope ratios ( δ 18 O) and stable hydrogen isotope ratios ( δ 2 H or δ D) to derive paleosalinity. First, I evaluate the potential and limitations of existing methods based on δ 18 O and δ D separately. Next, I propose a new theoretical framework for the combined use of δ 18 O and δ D to constrain the impact of the hydrological cycle on the surface waters and to thus characterize changes in surface water salinity. This new method is accompanied by an error propagation exercise to demonstrate its limitations and areas of potential improvement. A feasible strategy is outlined for achieving reconstructions of paleosalinity change with an uncertainty of 1 practical salinity unit or less with the newly proposed method (especially in regions with high deuterium excess values).