H11 meltwater and standard 127&thinsp;ka Last Interglacial simulations suggest more modest peak temperatures for both Greenland and Antarctica: a multi-model study of water isotopes

Sime, Louise C.; Sivankutty, Rahul; Malmierca-Vallet, Irene; Goursaud Oger, Sentia; LeGrande, Allegra N.; McClymont, Erin L.; de Boer, Agatha; Cauquoin, Alexandre; Werner, Martin

doi:https://doi.org/10.5194/cp-21-1725-2025

Articles | Volume 21, issue 10

https://doi.org/10.5194/cp-21-1725-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/cp-21-1725-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 21, issue 10

Research article

|

08 Oct 2025

Research article |

| 08 Oct 2025

H11 meltwater and standard 127 ka Last Interglacial simulations suggest more modest peak temperatures for both Greenland and Antarctica: a multi-model study of water isotopes

Louise C. Sime, Rahul Sivankutty, Irene Malmierca-Vallet, Sentia Goursaud Oger, Allegra N. LeGrande, Erin L. McClymont, Agatha de Boer, Alexandre Cauquoin, and Martin Werner

Data sets

More modest peak temperatures during the Last Interglacial for both Greenland and Antarctica suggested by multi-model isotope simulations Louise Sime et al. https://doi.org/10.5281/zenodo.14640495

Last Interglacial summer air temperature observations for the Arctic (Version 1.0) Maria Guarino and Louise Sime https://doi.org/10.5285/9ab58d27-596a-472c-a13e-2dcd68612082

Last interglacial and penultimate glacial sea surface temperature anomalies for the region south of 40°S, resampled to 2000 year resolution David M. Chandler and Petra M. Langebroek https://doi.org/10.1594/PANGAEA.938620

MIS 5e Southern Ocean September sea-ice concentrations and summer sea-surface temperatures reconstructed from marine sediment cores using a MAT diatom transfer function Matthew Chadwick et al. https://doi.org/10.1594/PANGAEA.936573

The four paleoclimate data syntheses for the article "Assessment of the southern polar and subpolar warming in the PMIP4 Last Interglacial simulations using paleoclimate data syntheses" Qinggang Gao et al. https://doi.org/10.5281/zenodo.11079974

Short summary

We used climate models to study how stable water isotopes in ice cores changed in the Arctic and Antarctica during the warm Last Interglacial (LIG) period. Whilst standard simulations underestimate polar warming, when the effects of ice sheet meltwater from the preceding deglaciation are included, there is a much better match with observations. Findings suggest that previous estimates of LIG Arctic warming were too high. Understanding these past polar changes can help improve future predictions.