Tree-ring stable isotopes are increasingly used across climate and environmental science, ecology, and hydrology. Open-science policies require data availability and transparency, yet raw isotope measurement databases require expert processing before they produce interpretable chronologies. Although technically open, such datasets are often scientifically inaccessible to non-experts, limiting reuse, reproducibility, and cross-disciplinary integration. The final tree-ring stable-isotope chronologies should be treated as primary geochemical data products, from which climate or physiological reconstructions are derived. Their scientific value reflects methodological decisions applied during processing and cannot be reconstructed from raw data alone. Unlike unprocessed measurements, final chronologies enable direct comparison across sites, archives, and disciplines and allow independent verification of published reconstructions. Archiving final chronologies alongside raw measurements and derived climate or physiological variables, in accordance with FAIR data principles, will strengthen transparency, comparability, and long-term scientific impact. Here, we present an initial set of recommendations from the authors' perspective, intended to stimulate broader community discussion towards the development of common practices for tree-ring stable-isotope data archiving.
Over recent decades, compilations of palaeo-records have proliferated, many with an emphasis on suitability for climate reconstruction. However, much less attention and resources have been directed towards the protection and documentation of the sample material that underlies the data series in these online database compilations. Here, we document an important tree-ring archive from the Stanley River in Tasmania, Australia. This archive contains wood samples stretching back as far as 43,000 BP (years before present). We describe the magnitude of the collection, the time frame covered, and the proportion of dated material included in a chronology. We highlight relatively new quantitative wood anatomy data derived from samples in the collection that exhibit a stronger climate signal than ring widths, demonstrating insights that emerging technologies can yield from collections such as this. The time span covered by the collection also makes it potentially important for calibration of a high resolution 14C curve for the Southern Hemisphere. A large proportion of the material has not yet been dated, or scientifically exploited. Therefore, there is a growing need to understand what physical material exists, and to maintain and document the raw sample material to support the future use of the physical material. We aim to highlight the immense scientific potential of this, and other collections like it.
Dendrochronology and all its subfields rely on developing chronologies from the widths of annual increments in tree wood samples. Measuring ring width and interpreting missing or double rings in a sample can follow best practices and the principle of crossdating, but still inherently carries some subjectivity or observer-bias in precisely how rings are measured and what are the criteria for missing or double rings. Therefore, archiving the original digital images upon which measurements are made, alongside the observer’s interpretations, is crucial for transparency and reproducibility in dendrochronology. Here, we present a new software tool, TreeTracer, linked to a virtual image and measurement repository, TreeTrove. The software includes ring detection features and the ability to measure in 1-D or 2-D on image files or in 3-D on computed tomography (CT) scans. Measurements conducted in 2-D or 3-D include measurement uncertainties, enabling dendrochronology data analyses to consider ring-width precision in down-stream error propagation. Most crucially, the software automatically curates images and files storing observer interpretation onto the TreeTrove server. While there are privacy controls for pre-publication datasets, published data—including the original image and ring interpretation—should be made openly accessible, which can be easily accomplished in the combined TreeTracer-TreeTrove system. Overall, the new software and data storage system presents a path forward for dendrochronology to be aligned with the principles of data findable, accessible, interoperable, and reuseable (FAIR).
