EGU26-9284, updated on 14 Mar 2026
https://doi.org/10.5194/egusphere-egu26-9284
EGU General Assembly 2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
Poster | Monday, 04 May, 14:00–15:45 (CEST), Display time Monday, 04 May, 14:00–18:00
 
Hall X5, X5.215
Assessing the issue of the water isotope signal loss in the BEOIC ice core. A model and high-resolution data perspective.
Caroline Juelsholt1, Bo Møllesøe Vinther1, Maria Hörhold2, Melanie Behrens2, Frank Wilhelms2,3, Johannes Freitag2, Ilka Weikusat2,4, Daniela Jansen2, Thomas Laepple5,6,7, Bénédicte Minster8, Amaelle Landais8, Hans Christian Steen-Larsen9, Natthaporn Phumchat9, Barbara Stenni10, Matteo Salvini10, Carlo Barbante10, Frederic Parrenin11, Emma Samin8, Federico Scoto10, and Vasileios Gkinis1
Caroline Juelsholt et al.
  • 1Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
  • 2Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
  • 3Geoscience Center, University of Göttingen, Göttingen, Germany
  • 4Department of Geosciences, Tübingen University, Tübingen, Germany
  • 5Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Potsdam, Germany
  • 6Faculty of Geosciences, University of Bremen, Bremen, Germany
  • 7MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
  • 8Laboratoire des Sciences du Climat et de l’Environnement, IPSL, CEA-CNRS-UVSQ, Gif-sur-Yvette, France
  • 9Geophysical Institute, University of Bergen, Bergen, Norway
  • 10Ca' Foscari University of Venice, Department of Environmental Science, Informatics and Statistics, Venice-Mestre, Italy
  • 11Université Grenoble Alpes, CNRS, INRAE, IRD, Grenoble INP, IGE, Grenoble, France

A new deep ice-core record from the East Antarctic Plateau reaching at least 1.2 million years is now available through the Beyond EPICA Oldest Ice Core project (BEOIC). This record spans the Mid-Pleistocene Transition (MPT), when glacial-cycle pacing shifted from ~40 kyr to ~100 kyr, and therefore offers key constraints when combined water-isotope and greenhouse-gas measurements are interpreted together.

Recovering an accurate water-isotope signal from the deepest and oldest ice is challenging because diffusion in solid ice attenuates high-frequency variability. High-precision, high-resolution measurements combined with physically based estimates of isotope diffusion can be used to quantify signal attenuation and assess the feasibility of signal deconvolution.

Here, we present a combined modelling and data study that quantifies diffusion-driven attenuation of the water isotope signal along the BEOIC using updated age–depth information and borehole temperature constraints. We apply the resulting transfer functions to high-resolution isotope sections from multiple depths to evaluate the recoverable bandwidth and to test spectral/Wiener restoration approaches, including the impact of measurement noise and sampling resolution on the reconstruction.

How to cite: Juelsholt, C., Vinther, B. M., Hörhold, M., Behrens, M., Wilhelms, F., Freitag, J., Weikusat, I., Jansen, D., Laepple, T., Minster, B., Landais, A., Steen-Larsen, H. C., Phumchat, N., Stenni, B., Salvini, M., Barbante, C., Parrenin, F., Samin, E., Scoto, F., and Gkinis, V.: Assessing the issue of the water isotope signal loss in the BEOIC ice core. A model and high-resolution data perspective., EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-9284, https://doi.org/10.5194/egusphere-egu26-9284, 2026.