| 1. |
- Björklund, J., et al.
(författare)
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Scientific Merits and Analytical Challenges of Tree-Ring Densitometry
- 2019
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Ingår i: Reviews of geophysics. - 8755-1209 .- 1944-9208. ; 57:4, s. 1224-1264
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Forskningsöversikt (refereegranskat)abstract
- X-ray microdensitometry on annually resolved tree-ring samples has gained an exceptional position in last-millennium paleoclimatology through the maximum latewood density (MXD) parameter, but also increasingly through other density parameters. For 50 years, X-ray based measurement techniques have been the de facto standard. However, studies report offsets in the mean levels for MXD measurements derived from different laboratories, indicating challenges of accuracy and precision. Moreover, reflected visible light-based techniques are becoming increasingly popular, and wood anatomical techniques are emerging as a potentially powerful pathway to extract density information at the highest resolution. Here we review the current understanding and merits of wood density for tree-ring research, associated microdensitometric techniques, and analytical measurement challenges. The review is further complemented with a careful comparison of new measurements derived at 17 laboratories, using several different techniques. The new experiment allowed us to corroborate and refresh long-standing wisdom but also provide new insights. Key outcomes include (i) a demonstration of the need for mass/volume-based recalibration to accurately estimate average ring density; (ii) a substantiation of systematic differences in MXD measurements that cautions for great care when combining density data sets for climate reconstructions; and (iii) insights into the relevance of analytical measurement resolution in signals derived from tree-ring density data. Finally, we provide recommendations expected to facilitate futureinter-comparability and interpretations for global change research.
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| 2. |
- Alexander, Steven M., et al.
(författare)
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Qualitative data sharing and synthesis for sustainability science
- 2020
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Ingår i: Nature Sustainability. - : Springer Science and Business Media LLC. - 2398-9629. ; 3:2, s. 81-88
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Tidskriftsartikel (refereegranskat)abstract
- Opportunities, challenges and recommended targeted actions to accelerate qualitative data sharing to address complex socio-environmental problems Socio-environmental synthesis as a research approach contributes to broader sustainability policy and practice by reusing data from disparate disciplines in innovative ways. Synthesizing diverse data sources and types of evidence can help to better conceptualize, investigate and address increasingly complex socio-environmental problems. However, sharing qualitative data for re-use remains uncommon when compared to sharing quantitative data. We argue that qualitative data present untapped opportunities for sustainability science, and discuss practical pathways to facilitate and realize the benefits from sharing and reusing qualitative data. However, these opportunities and benefits are also hindered by practical, ethical and epistemological challenges. To address these challenges and accelerate qualitative data sharing, we outline enabling conditions and suggest actions for researchers, institutions, funders, data repository managers and publishers.
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