Terzer-Wassmuth, S., Wassenaar, L. I., Welker, J. M., & Araguás-Araguás, L. J. (2021). Improved high-resolution global and regionalized isoscapes of δ18O, δ2H and d-excess in precipitation. Hydrological Processes, 35( 6), e14254. https://doi.org/10.1002/hyp.14254
Improved high-resolution global and regionalized isoscapes of δ¹⁸O, δ²H and d-excess in precipitation
|Author:||Terzer-Wassmuth, Stefan1; Wassenaar, Leonard I.1; Welker, Jeffrey M.2,3;|
1Isotope Hydrology Section, International Atomic Energy Agency, Vienna, Austria
2Ecology and Genetics Research Unit, University of Oulu, Oulu, Finland
3Department of Biological Sciences, University of Alaska Anchorage, Anchorage, Alaska, USA
|Persistent link:|| http://urn.fi/urn:nbn:fi-fe2021102552182
John Wiley & Sons,
|Publish Date:|| 2022-05-28
Patterns of δ¹⁸O and δ²H in Earth’s precipitation provide essential scientific data for use in hydrological, climatological, ecological and forensic research. Insufficient global spatial data coverage promulgated the use of gridded datasets employing geostatistical techniques (isoscapes) for spatiotemporally coherent isotope predictions. Cluster-based isoscape regionalization combines the advantages of local or regional prediction calibrations into a global framework. Here we present a revision of a Regionalized Cluster-Based Water Isotope Prediction model (RCWIP2) incorporating new isotope data having extensive spatial coverage and a wider array of predictor variables combined with high-resolution gridded climatic data. We introduced coupling of δ¹⁸O and δ²H (e.g., d-excess constrained) in the model predictions to prevent runaway isoscapes when each isotope is modelled separately and cross-checked observed versus modelled d-excess values. We improved model error quantification by adopting full uncertainty propagation in all calculations. RCWIP2 improved the RMSE over previous isoscape models by ca. 0.3 ‰ for δ¹⁸O and 2.5 ‰ for δ²H with an uncertainty <1.0 ‰ for δ¹⁸O and < 8 ‰ for δ²H for most regions of the world. The determination of the relative importance of each predictor variable in each ecoclimatic zone is a new approach to identify previously unrecognized climatic drivers on mean annual precipitation δ¹⁸O and δ²H. The improved RCWIP2 isoscape grids and maps (season, monthly, annual, regional) are available for download at https://isotopehydrologynetwork.iaea.org.
|Type of Publication:||
A1 Journal article – refereed
|Field of Science:||
1181 Ecology, evolutionary biology
1172 Environmental sciences
Funding for this research was provided by the International Atomic Energy Agency (STW, LIW, LA), United States National Science Foundation (JMW) and a UArctic Research Chairship at the Oulun Yliopisto, Finland (JMW).
The gridded data are available from IAEA-IHN (https://isotopehydrologynetwork.iaea.org). Numerical GNIP data can be obtained from https://nucleus.iaea.org/wiser.
© 2021 John Wiley & Sons Ltd. This is the peer reviewed version of the following article: Terzer-Wassmuth, S., Wassenaar, L. I., Welker, J. M., & Araguás-Araguás, L. J. (2021). Improved high-resolution global and regionalized isoscapes of δ18O, δ2H and d-excess in precipitation. Hydrological Processes, 35( 6), e14254, which has been published in final form at https://doi.org/10.1002/hyp.14254. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.