1,1,1,1,1,1,2,3,3,4,3,3,3,3,5,6,7,- 1LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif-sur-Yvette, France(benedicte.minster@lsce.ipsl.fr)
- 2Ca' Foscari of Venice, Department of Environmental Sciences, Informatics and Statistics, Mestre (Venice), Italy
- 3Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Am Alten Hafen 26, 27568 Bremerhaven, Germany
- 4University of Göttingen, Geoscience Center, Goldschmidtstr. 1–3, 37077 Göttingen, Germany
- 5Department of Geosciences, Tübingen University, Tübingen, Germany
- 6Geophysical Institute, University of Bergen and Bjerknes Center for Climate Research, Bergen, Norway
- 7Physics of Ice Climate and Earth, Niels Bohr Institute, University of Copenhagen, Tagensvej 16, 2200, Copenhagen, Denmark
- *A full list of authors appears at the end of the abstract
Water stable isotope records from Antarctic ice cores provide exceptional paleoclimatic information, currently spanning the last 800,000 years from the EPICA Dome C ice core (EDC). The recently retrieved Beyond EPICA Little Dome C (BELDC) ice cores should enable us to extend continuous Antarctica paleoclimate records back to at least 1.2 or even 1.5 million years ago, document past Antarctic climate and water cycle variability, and compare these new records with information extracted from other paleoclimatic archives.
The quantification of reliable past climate information based on high resolution water isotope records in deep Antarctic ice cores requires to characterize post-deposition processes which alter the initial precipitation isotopic composition. The isotopic composition of surface snow is affected by processes such as sublimation, hoar formation and snow redeposition. Then, diffusion smoothes isotopic profiles both in the firn and in the ice. Such processes can be particularly important in very low accumulation sites such as Little Dome C, and for very old ice.
For this purpose, we explore insights from new high-resolution measurements of δ18O of water from recent Little Dome C (LDC) firn cores and BELDC ice core, with a focus on three specific time slices.
First, we present the δ18O continuous flow analysis over the top 84 m of the LDC firn, spanning the past 2154 years based on volcanic age markers. This allows to estimate the LDC accumulation rate at approximately 24 mmwe.yr-1. Our record is confronted to series generated by a virtual firn core model. Surface mixing plays an important role in reshaping the recorded signal within the first 3 m, with a best agreement obtained with an 8 cm mixing layer. Our results highlight that the diffusion is overestimated based on classical diffusion modelling.
We then focus on the last interglacial period, MIS5, and compare 2.5 and 10 cm dD resolution measurements from BELDC with earlier 11 cm records from EPICA Dome C, where the highest δD anomaly of the last 800 ka is observed.
Finally, we present 2.5 cm resolution δD records from BELDC spanning the time period prior to the EPICA Dome C record, from MIS23 (around 900 ka) to warm MIS31(around 1.08 to 1 Ma).
Carlo Barbante [2], Melanie Behrens [3], Enrico Biscaro [2], Pascal Bohler [3], Louisa Brückner [1], Elodie Brugère [1], Thomas Combacal [1], Elisa Conrad [3], Denise Diekstall [3], Giuliano Dreossi [2], Hubertus Fisher [8], Elise Fourré [1], Johannes Freigtag [3], Vasileios Gkinis [7], Maria Hörhold [3], Daniela Jansen [3], Anna Maria Klüssendorf [1], Thomas Laepple [10], Amaëlle Landais [1], Hanno Meyer [10], Bénédicte Minster [1], Inès Ollivier [1], Adrien Ooms [1], Frédéric Parrenin [9], Natthaporn Phumchat [6], Matteo Salvini [2], Emma Samin [1], Hans Christian Steen-Larsen [6], Barbara Stenni [2], Birthe Twarloh [3], Bo Møllesøe Vinther [7], Ilka Weikusat [3,5], Martin Werner [3], Frank Wilhelms [3,4]. Affiliations : [1] LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif-sur-Yvette, France. [2] Ca' Foscari of Venice, Department of Environmental Sciences, Informatics and Statistics, Mestre (Venice), Italy. [3] Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Am Alten Hafen 26, 27568 Bremerhaven, Germany. [4] University of Göttingen, Geoscience Center, Goldschmidtstr. 1–3, 37077 Göttingen, Germany. [5] Department of Geosciences, Tübingen University, Tübingen, Germany. [6] Geophysical Institute, University of Bergen and Bjerknes Center for Climate Research, Bergen, Norway. [7] Physics of Ice Climate and Earth, Niels Bohr Institute, University of Copenhagen, Tagensvej 16, 2200, Copenhagen, Denmark. [8] Climate and Environmental Physics, Physics Institute and Oeschger Center for Climate Change Research, University of Bern, Sidlerstrasse 5, Bern, Switzerland. [9] Université Grenoble Alpes, CNRS, IRD, Grenoble INP, INRAE, IGE, 38000 Grenoble, France. [10] Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Telegrafenberg A45, 14473 Potsdam, Germany.
How to cite: Minster, B., Samin, E., Landais, A., Fourré, E., Casado, M., Ooms, A., Dutrievoz, N., Agosta, C., Masson-Delmotte, V., Combacal, T., Stenni, B., Salvini, M., Hörhold, M., Wilhelms, F., Behrens, M., Freigtag, J., Jansen, D., Weikusat, I., Steen-Larsen, H. C., and Gkinis, V. and the The Beyond Epica water isotopes consortium: High resolution water isotopic records on the Little Dome C firn cores and Beyond EPICA ice core for past climate and atmospheric water cycle reconstructions, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-5446, https://doi.org/10.5194/egusphere-egu26-5446, 2026.
