Exploring the paleoclimatic potential of a 1000-year tree-ring chronology from archaeological and living oaks from central France
Résumé
Tree rings are valuable archives for reconstructing natural climate variability with high temporal resolution over the last millennium, providing critical context for current global warming and enhancing our understanding of anthropogenic and natural climate forcings. However, global climate reconstructions rely on regional studies that are unevenly distributed across space and time. In Europe, tree-ring widths have been widely used to reconstruct temperature and precipitation, yet millennial-scale climate reconstructions are lacking in France, particularly for central France and, more broadly, lowland regions. New data from this region would enhance our understanding of hydroclimatic variability and its drivers in western Europe while also improving the accuracy of climate reconstructions for both European and Northern Hemisphere. We examined the feasibility of constructing a millennial chronology using archaeological material and living trees from central France, collected and dated over the last few decades by numerous French dendrochronologists. The initial dataset consisted of 5,745 archaeological wood samples and 129 living oaks, spanning 45-48.5°N and -2-5.5°E, and covering from 696 to 2023 CE. From this dataset, we produced several reconstructions using various series selection criteria, detrending methods, and calibration and verification methods across different time periods. These reconstructions were then compared, and the decision-making process was evaluated. The reconstructions’s skills, consistent with results obtained in previous studies, along with the agreement between our reconstruction and published European climate reconstructions and paleo-reanalyses, highlight the potential of this French new dataset for reconstructing May-July hydroclimatic variability over the last millennium in this region of Europe.