Dual archive paleotemperature records over two pre-LGM stadial/interstadials in East Central Europe

The generally cold climate of the last glacial period was interrupted by numerous abrupt shifts to warmer interstadial conditions in the North Atlantic. The effects of this Dansgaard–Oeschger (D–O) type climatic variability have been found in a number of European and Asian terrestrial paleoclimate archives, including speleothems, lakes and loess deposits. However, only very few of the already sparse precisely dated records provide quantitative information on stadial-interstadial temperature variations over this time period. This is a major impediment to resolving the cause and geographical propagation of D-O events, as well as to understanding the impact they have on continental climates and environments.

Here we present carbonate clumped isotope (Δ₄₇)-based active season paleotemperature (AST) estimates from land snails recovered from Greenland Stadial/Interstadial (GS/GI) 5 and 3 age loess at the Dunaszekcső loess site (Hungary), based on a uniquely detailed AMS ¹⁴C age dataset, alongside a new flowstone (PK-6, Bükkösd, Hungary) stable isotope-based temperature change record ²³⁰Th-dated to 30-26 ka. Stadial ASTs of the investigated periods were found to be in the range of 7–13 °C, corresponding to T_annual of 0–6 °C and T_July of 11–17 °C, agreeing well with the range of model simulation results for the region. Interstadial AST values reconstructed for GI-5.1 and 3 (16–18 °C) indicate warm summers (T_July: 20–22 °C) and relatively high annual mean temperatures (T_annual: 9–11 °C), matching present-day values. The PK-6 flowstone δ¹⁸O_calcite-based temperature change estimates (~0.2 ‰ °C^–1 δ¹⁸O/T gradient) reveal a 7–10 °C T_annual rise for the warmest phases of GI-3 and 4 compared to stadial temperatures, in very good agreement with the land snail TΔ₄₇ values.

Our results show that stadial-interstadial climate variability in East Central Europe was of comparable magnitude to that in Greenland. We propose that large scale ocean-atmospheric variability (NAO-AMO) imparts a major control on transmitting abrupt North Atlantic climate event signals into continental Europe during the last glacial.

 

This study was funded by the Hungarian National Research, Development and Innovation Office to GÚ (OTKA PD-108639) and SK (OTKA KH-125584). TS is grateful for the support of the Swedish Research Council (2017-03888).