Publication details
Pan-alpine summer temperatures since 742 CE
| Authors | |
|---|---|
| Year of publication | 2025 |
| Type | Peer-reviewed scientific article |
| Magazine / Source | Dendrochronologia |
| MU Faculty or unit | |
| Citation | |
| web | https://www.sciencedirect.com/science/article/pii/S1125786525001468 |
| Doi | https://doi.org/10.1016/j.dendro.2025.126432 |
| Keywords | Climate reconstruction; European Alps; Larix decidua; Maximum latewood density; MXD; Paleoclimate |
| Description | Albeit labor-intensive, tree-ring maximum latewood density (MXD) has become a prime proxy to reconstruct inter-annual to multi-centennial climate variability. We here combine such data from five valleys in Austria, France and Switzerland to present a June-September temperature history for the European Alps reaching back to 742 CE. The pan-alpine record correlates at r1880–2023 =?0.89 with observational data and provides evidence for a prolonged Little Ice Age (LIA) from the 1250s to 1850s CE, during which summer temperatures were 0.59?°C cooler compared to the preceding Medieval Warm Period (MWP) from the 880s to 1240s CE. Temperatures rose by 3.65?°C from the coldest decade in the 1810s, which includes the 1816 CE post-Tambora “year without a summer”, to the warmest decade in the 2010s. The warmest summer in our reconstruction occurred in 2003 CE (+?2.71?°C) and exceeds the warmest naturally forced summer in 970 CE (+?2.19?°C) by more than 0.5?°C. This difference is non-significant, however, if we consider the increasing uncertainties back in time when fewer sites and trees contributed to the reconstruction. The pan-alpine record is the result of conducting MXD measurements over the past two decades in Swiss and German laboratories and sets a new standard in terms of explained variance and pre-instrumental temperature variability estimation in the European Alps. |