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Abstract. The hydrogen and oxygen stable isotope ratios of water have been used to identify sources, transport pathways, and phase-change processes within the water cycle, supporting hydrologic, forensic, ecologic, and hydroclimatic investigations. Here, we introduce a unique, open-access, global database of stable water isotope ratios (δ18O, δ17O, and δ2H) from various water types. This database facilitates data preservation, supports standardized metadata collection, and decreases the time investment for meta-analytic research and reference dataset discovery. As of July 2019, the database includes 231 586 samples from 52 210 sites, associated with 218 projects, spanning 1949 through 2019. Key information stored includes the hydrogen and oxygen isotope ratios, water type, collection date and time, site location, and project information. To promote rapid data discovery and collaboration, the database exposes metadata such as data owner contact information of embargoed data, but only permits downloads of public data. The database is supported by two companion apps, one for processing and upload of analytical data from laboratories and the other an iOS application that supports the digital collection of sample metadata.
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This content will become publicly available on April 1, 2026
Global patterns in observed hydrologic processes
To manage water resources and forecast river flows, hydrologists seek to understand how water moves from precipitation, through watersheds, into river channels. However, we lack fundamental information on the spatial distribution and physical controls on global hydrologic processes. This information is needed to provide theoretical support for large-domain model simulations. Here, to address this issue, we present a global, searchable database of 400 research watersheds with published descriptions of dominant hydrologic flow pathways. This knowledge synthesis approach leverages decades of grant funding, fieldwork effort and local expertise. We use the database to test longstanding hypotheses about the roles of climate, biomes and landforms in controlling hydrologic processes. We show that aridity predicts the depth of water flow pathways and that terrain and biomes predict the prevalence of lateral flow pathways. These new data and search capabilities support efficient hypothesis testing to investigate emergent patterns that relate landscape organization to hydrologic function.
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- Award ID(s):
- 2322510
- PAR ID:
- 10623751
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- Nature Water
- Volume:
- 3
- Issue:
- 4
- ISSN:
- 2731-6084
- Page Range / eLocation ID:
- 497 to 506
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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