Tephrochronology and absolute centennial scale synchronisation of European and Greenland records for the last glacial to interglacial transition: A case study of Soppensee and NGRIP

The tephrostratigraphy of Soppensee, Switzerland, is presented here for the first time, with new geochemical data for four tephra layers, derived from three volcanic centres. The best available age estimates for the Laacher See Tephra and Vedde Ash layers are incorporated into a revision of the radiocarbon-based Bayesian age-model for the last glacial to interglacial transition at Soppensee, which is used to explore synchronicity of climatic events between Europe and the North Atlantic. Local temperature changes, recorded by biotic and abiotic proxies in Soppensee, appear to shift in phase with the oxygen isotope signal in Greenland at the onset of the Younger Dryas; however with the clarity of improved precision, an apparent offset that likely results from a dating artefact, is seen between records at the termination of the stadial event. From a methodological standpoint, the results clearly show that only by establishing detailed and independent chronological frameworks can abrupt climatic variability be compared between different regions with sufficiently high temporal precision to addresses the notion of hemispheric climatic synchronicity at the centennial scale in the Late Quaternary. Continuing to develop such approaches is therefore essential in order to understand how far in time and space the climate has behaved in such a way.