The synchronization of findings from two natural climate records – a speleothem from the Herbstlabyrinth Cave in Hesse (Germany) and ice cores from Greenland – sheds light on the timeline of sudden climate shifts in Central Europe. Analysis indicates that the catastrophic eruption of the Laacher See volcano in modern Rhineland-Palatinate happened earlier than previously believed, suggesting it could not have triggered the rapid cold spell that occurred around 13,000 years ago. This conclusion has been corroborated by researchers from Heidelberg University and Mainz University. In addition to accurately determining the eruption’s date, the research team also assessed its effects on climate.
The last eruption of the Laacher See volcano is known to be one of the most destructive events in the last two million years, with its impacts felt as far away as northern Italy, Scandinavia, and Russia. The timing of this eruption and its connection to a sudden cold event known as the Younger Dryas has sparked significant academic discussion. In 2021, researchers attempted a new dating classification utilizing radiocarbon dating of tree trunks. Findings indicate that the eruption occurred approximately 130 years earlier than previously thought. The team from Heidelberg and Mainz successfully validated this new timing using a speleothem from the Herbstlabyrinth Cave in Breitscheid, Hesse.
Since volcanic eruptions are characterized by high sulfur emissions, the corresponding volcanic markers would also need to be detected in the speleothem. “The high-resolution sulfur and oxygen isotope analyses conducted with the ion probe in Heidelberg were crucial for this identification,” states Prof. Dr. Axel Schmitt, a researcher at Curtin University in Perth (Australia) and adjunct professor at Heidelberg University. The ion probe allows for the measurement of various isotope ratios and trace elements at a micrometer scale.
The geochemical data obtained was then matched with an unassigned sulfate peak found in Greenland’s ice cores. The statistical analysis was led by Prof. Dr. Denis Scholz, an authority on dating historical climate variations at the Institute for Geosciences at Mainz University. “This synchronization marks a significant advancement in the dating of climate and environmental records, as no precisely dated time marker prior to the Younger Dryas cooling was known until now,” notes Dr. Sophie Warken, who studies climate changes of past eras at the Institutes of Earth Sciences and Environmental Physics at Heidelberg University.
Dr. Warken explains that the new dating reveals that the eruption occurred about 150 years before the Younger Dryas cold event. “This rules out a direct cause-and-effect relationship between the volcanic eruption and the sudden climate shift,” she clarifies, identifying herself as the primary author of the study. By pinpointing the sulfate spikes in the Greenland ice cores, the team was able to infer the climatic events at the onset of the Younger Dryas. Previously, it remained uncertain whether the climatic shifts during this roughly 1,000-year cold spell were simultaneous across the North Atlantic and Europe, or if they developed gradually from Greenland to Central Europe over decades or even centuries. “Our results indicate that a significant temperature drop happened concurrently, suggesting a direct link between the Central European and Arctic climates,” Dr. Warken explains.
This research paves the way for enhanced understanding of intricate climatic interactions in the past. The findings also provide a strong foundation for more accurate predictions of future climate trends, as highlighted by Sophie Warken. This study was part of the collaborative project “Terrestrial Magmatic Systems” (TeMaS), conducted by Heidelberg University, Goethe University Frankfurt (Main), and Mainz University, with support from the Rhineland-Palatinate state, among other sources. Additional funding came from the German Research Foundation and the European Research Council. The study’s results were published in the journal “Science Advances.”
