EGU2020-13653
https://doi.org/10.5194/egusphere-egu2020-13653
EGU General Assembly 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

Spatial variability of surface snow isotopic composition on the East Antarctic Plateau and implications for climate reconstructions

Maria Hörhold1, Alexander Weinhart1, Sepp Kipfstuhl1, Johannes Freitag1, Georgia Micha1,2, Martin Werner1, and Gerrit Lohmann1,2
Maria Hörhold et al.
  • 1Alfred-Wegener-Institute, Glaciology, Bremerhaven, Germany (maria.hoerhold@awi.de)
  • 2Institute of Environmental Physics, University of Bremen, Bremen, Germany

The reconstruction of past temperatures based on ice core records relies on the quantitative but empirical relationship of stable water isotopes and annual mean temperature. However, its relation varies through space and time. On the East Antarctic Plateau, temperature reconstructions from ice cores are poorly constrained or even fail on decadal and smaller time scales. The observed discrepancy between annual mean temperature and isotopic composition partly relies on surface processes altering the signal after deposition but also, to a great deal, on spatially coherent processes prior to or during deposition. However, spatial coverage over larger areas on the East Antarctic Plateau is challenging. We here present in-situ measurements of the isotopic composition of surface snow with unprecedented statistical quality and coverage. 1m surface snow profiles were collected during an overland traverse between Kohnen station and Plateau Station, covering a 1200km long transect. We explore regional differences of the temperature-isotope relationship and discuss possible mechanisms affecting the isotopic composition in areas with accumulation rates lower than 60mmWEa^-1.

How to cite: Hörhold, M., Weinhart, A., Kipfstuhl, S., Freitag, J., Micha, G., Werner, M., and Lohmann, G.: Spatial variability of surface snow isotopic composition on the East Antarctic Plateau and implications for climate reconstructions, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13653, https://doi.org/10.5194/egusphere-egu2020-13653, 2020

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Presentation version 1 – uploaded on 04 May 2020
  • CC1: slide 7, Marie G. P. Cavitte, 07 May 2020