A high-resolution speleothem proxy record of the Late Glacial in the European Alps: extending the NALPS19 record until the beginning of the Holocene

Previous research has shown that speleothems from the northern rim of the European Alps captured submillennial-scale climate change during the last glacial period with exceptional sensitivity and resolution, mimicking Greenland ice-core records. Here we extend this so-called NALPS19 record across the Late Glacial using two stalagmites which grew continuously into the Holocene. Both specimens show the same high-amplitude delta O-18 signal as Greenland ice cores down to decadal resolution. The start of the warming at the onset of the equivalent of Greenland Interstadial (GI) GI-1e at 14.66 +/- 0.18 ka agrees with the North Greenland Ice Core Project (NGRIP) (14.64 +/- 0.28 ka) and comprised a temperature rise of about 5-6 degrees C. The transition from the equivalent of GI-1a into the equivalent of Greenland Stadial (GS) GS-1 (broadly equivalent to the Younger Dryas) commenced at 13.02 +/- 0.13 ka which is consistent with NGRIP (12.80 +/- 0.26 ka) within errors. The onset of the Holocene started at 11.78 +/- 0.14 ka (11.65 +/- 0.10 ka at NGRIP) and involved a warming of about 4-5 degrees C. In contrast to delta O-18, delta C-13 values show no response to (sub)millennial climate shifts due to strong rock-buffering and only record a long-term trend of soil development starting with the rapid warming at 14.7 ka.

Automated summary

Previous research demonstrated that speleothems from the northern rim of the European Alps exhibit exceptional sensitivity and resolution in capturing submillennial-scale climate changes during the last glacial period, resembling Greenland ice-core records. The analysis of two stalagmites in this study confirmed the similarity in temperature rise at specific time points with the Greenland ice cores and also provided insights into the transition from cold stadial periods to warmer interstadial periods. Additionally, the study showed that delta C-13 values do not respond to short-term climate shifts due to rock-buffering effects but reflect a long-term trend of soil development linked to temperature changes.