(Table A1) Raw data for both AMT20 Atlantic Ocean transect samples and western Pacific Ocean transect (SO228 and SO256) samples

Sea surface salinity (SSS) is the least constrained major variable of the past (paleo) ocean but is fundamental in controlling the density of seawater and thus large-scale ocean circulation. The hydrogen isotopic composition (δD) of non-exchangeable hydrogen of algal lipids, specifically alkenones, has been proposed as a promising new proxy for paleo SSS. The δD of surface seawater is correlated with SSS, and laboratory culture studies have shown the δD of algal growth water to be reflected in the δD of alkenones. However, a large-scale field study testing the validity of this proxy is still lacking. Here we present the δD of open-ocean Atlantic and Pacific surface waters and coincident δD of alkenones sampled by underway filtration. […]

海水表面盐度（SSS）是过去（古）海洋中约束最少的重大变量，但对于控制海水密度以及由此产生的大规模海洋环流具有根本性影响。藻类脂质中不可交换氢的同位素组成（δD），尤其是长链烯酮，已被提议作为一种有潜力的新古海水表面盐度（paleo SSS）替代指标。表面海水的δD与SSS相关联，实验室培养研究表明，藻类生长水的δD在长链烯酮的δD中得到反映。然而，一项大规模现场研究以验证该替代指标的准确性尚属缺失。在本研究中，我们展示了大西洋和太平洋开放海域表层海水的δD以及通过现场过滤采集的长链烯酮的相应δD。