| Title | An overview on isotopic divergences - causes for instability of tree-ring isotopes and climate correlations |
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| Author | Savard, M M ;
Daux, V |
| Source | Climate of the Past vol. 16, 2020 p. 1223-1243, https://doi.org/10.5194/cp-16-1223-2020  Open Access |
| Image |  |
| Year | 2020 |
| Alt Series | Natural Resources Canada, Contribution Series 20190529 |
| Publisher | Copernicus Publication (EGU) |
| Document | serial |
| Lang. | English |
| Media | on-line; digital |
| File format | pdf |
| Subjects | environmental geology; Nature and Environment; Science and Technology; isotopic studies; isotopes; climate effects; carbon isotopes; oxygen isotopes |
| Illustrations | tables; schematic representations |
| Program | Environmental Geoscience
Sources |
| Released | 2020 07 13 |
| Abstract | Climatic reconstructions based on tree-ring isotopic series convey substantial information about past conditions prevailing in forested regions of the globe. However, in some cases, the relations
between isotopic and climatic records appear unstable over time, generating the “isotopic divergences”. Former reviews have thoroughly discussed the divergence concept for tree-ring physical properties but not for isotopes. Here we want to take stock
of the isotopic divergence problem, express concerns and stimulate collaborative work for improving paleoclimatic reconstructions. There are five main causes for divergent parts in isotopic and climatic series: (1) artefacts due to sampling and data
treatment, relevant for dealing with long series using subfossil stems; (2) stand dynamics, including juvenile effects mostly occurring in the early part of tree-ring series; (3) rise in atmospheric pCO2, which can directly influence the foliar
behaviour; (4) change in climate, which may modify the isotope-climate causal links; and finally (5) atmospheric pollution, which may alter leaf and root functions. Future paleoclimate research would benefit from interdisciplinary efforts designed to
develop further process-based models integrating multi-proxy inputs so as to help identify causes of isotopic divergences and circumvent some of them in inverse applications. |
| Summary | (Plain Language Summary, not published)
Climatic reconstructions based on tree-ring isotopic series convey substantial information about past conditions prevailing in forested regions of the
globe. However, in some cases, the relations between isotopes and specific climatic parameters appear unstable over time, generating periods of departures called the 'isotopic divergences'. Former literature reviews have thoroughly discussed the
divergence concept for tree-ring physical properties (width, density), but not for isotopes. In this article, we want to take stock of the isotopic divergence problem. We describe five main causes for diverging parts in isotopic and climatic series:
artefacts due to sampling and data treatment, stand dynamics, rise in atmospheric pCO2, change of climatic ambiance, and atmospheric pollution. In a final perspective, we discuss approaches to overcome isotopic divergences and promote new avenues for
climatic reconstruction. |
| GEOSCAN ID | 321798 |
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