Dansgaard-Oeschger cycles of the penultimate and last glacial period recorded in stalagmites from Türkiye

F Held; H Cheng; R L Edwards; O Tüysüz; K Koç; D Fleitmann

doi:10.1038/s41467-024-45507-5

Dansgaard-Oeschger cycles of the penultimate and last glacial period recorded in stalagmites from Türkiye

Nat Commun. 2024 Feb 8;15(1):1183. doi: 10.1038/s41467-024-45507-5.

Authors

F Held¹, H Cheng², R L Edwards³, O Tüysüz⁴, K Koç⁵, D Fleitmann⁶

Affiliations

¹ Department of Environmental Sciences, University of Basel, 4056, Basel, Switzerland. [email protected].
² Institute of Global Environmental Change, Xi'an Jiaotong University, 710054, Xi'an, China.
³ Department of Earth and Environmental Sciences, University of Minnesota, 55455, Minneapolis, USA.
⁴ Eurasia Institute of Earth Sciences, Istanbul Technical University, 34469, Istanbul, Türkiye.
⁵ Department of Geological Engineering, Akdeniz University, 07058, Antalya, Türkiye.
⁶ Department of Environmental Sciences, University of Basel, 4056, Basel, Switzerland. [email protected].

Abstract

The last glacial period is characterized by abrupt climate oscillations, also known as Dansgaard-Oeschger (D-O) cycles. However, D-O cycles remain poorly documented in climate proxy records covering the penultimate glacial period. Here we present highly resolved and precisely dated speleothem time series from Sofular Cave in northern Türkiye to provide clear evidence for D-O cycles during Marine Isotope Stage (MIS) 6 as well as MIS 2-4. D-O cycles are most clearly expressed in the Sofular carbon isotope time series, which correlate inversely with regional sea surface temperature (SST) records from the Black Sea. The pacing of D-O cycles is almost twice as long during MIS 6 compared to MIS 2-4, and could be related to a weaker Atlantic Meridional Overturning Circulation (AMOC) and a different mean climate during MIS 6 compared to MIS 2-4, leading most likely to a higher threshold for the occurrence of D-O cycles.