Global Stable Isotope Dataset for Surface Water

Abstract. Hydrogen and oxygen-stable isotopes are widely used as tracers of the water cycle, and surface water is an integral part of the water cycle. Compared with other water bodies, surface water is more susceptible to different natural and anthropogenic factors, and an accurate understanding of surface water changes is of great significance in ensuring regional water security, maintaining ecological balance, and promoting sustainable economic and social development. Due to the influence of observation conditions and instrumental analysis, global surface water isotopes' spatial and temporal distribution could be more balanced worldwide. For this reason, we have compiled and analyzed the stable hydrogen and oxygen isotope data in surface water from 22432 sampling stations worldwide from 1956 to 2023, with 102862 data records. The results found that (1) surface water stable isotopes are gradually depleted from the equator to the poles and from the coast to the interior. However, there are significant differences in the spatial and temporal distributions of surface water isotopes in different regions. (2) The variation of stable isotopes in surface water is controlled by geographic location, topographic conditions, and meteorological factors (especially temperature), and its heterogeneity is considerable. The global stable isotope dataset of surface water provides vital information for an in-depth understanding of the water cycle and climate change. It can provide essential data references for global water resource management and research. The Global Surface Water Stable Isotope Dataset is available at https://doi.org/10.17632/fs7rwp7fpr.1 (Zhu, 2024).