Mathieu Casado, Amaelle Landais, Ghislain Picard, Thomas Münch, Thomas Laepple, Barbara Stenni, Giuliano Dreossi, Alexey Ekaykin, Laurent Arnaud, Christophe Genthon, Alexandra Touzeau, Valerie Masson-Delmotte, Jean Jouzel
- The oldest ice core records are obtained from the East Antarctic Plateau. Water isotopes are key proxies to reconstructing past climatic conditions over the ice sheet and at the evaporation source. The accuracy of climate reconstructions depends on knowledge of all processes affecting water vapour, precipitation and snow isotopic compositions. Fractionation processes are well understood and can be integrated in trajectory-based Rayleigh distillation and isotope-enabled climate models. However, a quantitative understanding of processes potentially altering snow isotopic composition after deposition is still missing. In low-accumulation sites, such as those found in East Antarctica, these poorly constrained processes are likely to play a significant role and limit the interpretability of an ice core's isotopic composition.
By combining observations of isotopic composition in vapour, precipitation, surface snow and buried snow from Dome C, a deep ice core site on the East Antarctic Plateau, we found indications of a seasonal impact ofThe oldest ice core records are obtained from the East Antarctic Plateau. Water isotopes are key proxies to reconstructing past climatic conditions over the ice sheet and at the evaporation source. The accuracy of climate reconstructions depends on knowledge of all processes affecting water vapour, precipitation and snow isotopic compositions. Fractionation processes are well understood and can be integrated in trajectory-based Rayleigh distillation and isotope-enabled climate models. However, a quantitative understanding of processes potentially altering snow isotopic composition after deposition is still missing. In low-accumulation sites, such as those found in East Antarctica, these poorly constrained processes are likely to play a significant role and limit the interpretability of an ice core's isotopic composition.
By combining observations of isotopic composition in vapour, precipitation, surface snow and buried snow from Dome C, a deep ice core site on the East Antarctic Plateau, we found indications of a seasonal impact of metamorphism on the surface snow isotopic signal when compared to the initial precipitation. Particularly in summer, exchanges of water molecules between vapour and snow are driven by the diurnal sublimation-condensation cycles. Overall, we observe in between precipitation events modification of the surface snow isotopic composition. Using high-resolution water isotopic composition profiles from snow pits at five Antarctic sites with different accumulation rates, we identified common patterns which cannot be attributed to the seasonal variability of precipitation. These differences in the precipitation, surface snow and buried snow isotopic composition provide evidence of post-deposition processes affecting ice core records in low-accumulation areas.…
MetadatenVerfasserangaben: | Mathieu CasadoORCiD, Amaelle LandaisORCiD, Ghislain PicardORCiD, Thomas MünchORCiDGND, Thomas LaeppleORCiDGND, Barbara StenniORCiD, Giuliano Dreossi, Alexey EkaykinORCiD, Laurent Arnaud, Christophe GenthonORCiD, Alexandra TouzeauORCiD, Valerie Masson-DelmotteORCiD, Jean Jouzel |
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DOI: | https://doi.org/10.5194/tc-12-1745-2018 |
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ISSN: | 1994-0416 |
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ISSN: | 1994-0424 |
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Titel des übergeordneten Werks (Englisch): | The Cryosphere : TC ; an interactive open access journal of the European Geosciences Union |
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Verlag: | Copernicus |
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Verlagsort: | Göttingen |
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Publikationstyp: | Wissenschaftlicher Artikel |
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Sprache: | Englisch |
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Datum der Erstveröffentlichung: | 24.05.2018 |
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Erscheinungsjahr: | 2018 |
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Datum der Freischaltung: | 30.11.2021 |
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Band: | 12 |
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Ausgabe: | 5 |
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Seitenanzahl: | 22 |
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Erste Seite: | 1745 |
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Letzte Seite: | 1766 |
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Fördernde Institution: | Programme (FP7)/RC grant [306045]; Initiative and Networking Fund of the Helmholtz Association Grant [VG-NH900]; LGGE; LIPHY |
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Organisationseinheiten: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Geowissenschaften |
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DDC-Klassifikation: | 5 Naturwissenschaften und Mathematik / 55 Geowissenschaften, Geologie / 550 Geowissenschaften |
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Peer Review: | Referiert |
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Publikationsweg: | Open Access / Gold Open-Access |
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| DOAJ gelistet |
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Lizenz (Deutsch): | CC-BY - Namensnennung 4.0 International |
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Externe Anmerkung: | Zweitveröffentlichung in der Schriftenreihe Postprints der Universität Potsdam : Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe ; 716 |
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