On the similarity and apparent cycles of isotopic variations in East Antarctic snow pits
International audience Stable isotope ratios δ 18 O and δD in polar ice provide a wealth of information about past climate evolution. Snow-pit studies allow us to relate observed weather and climate conditions to the measured isotope variations in the snow. They therefore offer the possibility to te...
Published in: | The Cryosphere |
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Main Authors: | , , , , , |
Other Authors: | , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2018
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Subjects: | |
Online Access: | https://hal.archives-ouvertes.fr/hal-01806796 https://hal.archives-ouvertes.fr/hal-01806796/document https://hal.archives-ouvertes.fr/hal-01806796/file/tc-12-169-2018.pdf https://doi.org/10.5194/tc-12-169-2018 |
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ftunivnantes:oai:HAL:hal-01806796v1 |
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openpolar |
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Open Polar |
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Université de Nantes: HAL-UNIV-NANTES |
op_collection_id |
ftunivnantes |
language |
English |
topic |
[SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology |
spellingShingle |
[SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology Laepple, Thomas Munch, Thomas Casado, Mathieu Hoerhold, Maria Landais, Amaelle Kipfstuhl, Sepp On the similarity and apparent cycles of isotopic variations in East Antarctic snow pits |
topic_facet |
[SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology |
description |
International audience Stable isotope ratios δ 18 O and δD in polar ice provide a wealth of information about past climate evolution. Snow-pit studies allow us to relate observed weather and climate conditions to the measured isotope variations in the snow. They therefore offer the possibility to test our understanding of how isotope signals are formed and stored in firn and ice. As δ 18 O and δD in the snowfall are strongly correlated to air temperature, isotopes in the near-surface snow are thought to record the seasonal cycle at a given site. Accordingly , the number of seasonal cycles observed over a given depth should depend on the accumulation rate of snow. However , snow-pit studies from different accumulation conditions in East Antarctica reported similar isotopic variability and comparable apparent cycles in the δ 18 O and δD profiles with typical wavelengths of ∼ 20 cm. These observations are unexpected as the accumulation rates strongly differ between the sites, ranging from 20 to 80 mm w.e. yr −1 (∼ 6-21 cm of snow per year). Various mechanisms have been proposed to explain the isotopic variations individually at each site; however , none of these are consistent with the similarity of the different profiles independent of the local accumulation conditions. Here, we systematically analyse the properties and origins of δ 18 O and δD variations in high-resolution firn profiles from eight East Antarctic sites. First, we confirm the suggested cycle length (mean distance between peaks) of ∼ 20 cm by counting the isotopic maxima. Spectral analysis further shows a strong similarity between the sites but indicates no dominant periodic features. Furthermore, the apparent cycle length increases with depth for most East Antarctic sites, which is inconsistent with burial and compression of a regular seasonal cycle. We show that these results can be explained by isotopic diffusion acting on a noise-dominated isotope signal. The firn diffusion length is rather stable across the Antarctic Plateau and thus leads to ... |
author2 |
Alfred Wegener Institute Potsdam Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI) Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE) Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) Climate Sciences Department Bremerhaven Glaces et Continents, Climats et Isotopes Stables (GLACCIOS) Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) |
format |
Article in Journal/Newspaper |
author |
Laepple, Thomas Munch, Thomas Casado, Mathieu Hoerhold, Maria Landais, Amaelle Kipfstuhl, Sepp |
author_facet |
Laepple, Thomas Munch, Thomas Casado, Mathieu Hoerhold, Maria Landais, Amaelle Kipfstuhl, Sepp |
author_sort |
Laepple, Thomas |
title |
On the similarity and apparent cycles of isotopic variations in East Antarctic snow pits |
title_short |
On the similarity and apparent cycles of isotopic variations in East Antarctic snow pits |
title_full |
On the similarity and apparent cycles of isotopic variations in East Antarctic snow pits |
title_fullStr |
On the similarity and apparent cycles of isotopic variations in East Antarctic snow pits |
title_full_unstemmed |
On the similarity and apparent cycles of isotopic variations in East Antarctic snow pits |
title_sort |
on the similarity and apparent cycles of isotopic variations in east antarctic snow pits |
publisher |
HAL CCSD |
publishDate |
2018 |
url |
https://hal.archives-ouvertes.fr/hal-01806796 https://hal.archives-ouvertes.fr/hal-01806796/document https://hal.archives-ouvertes.fr/hal-01806796/file/tc-12-169-2018.pdf https://doi.org/10.5194/tc-12-169-2018 |
geographic |
Antarctic The Antarctic East Antarctica |
geographic_facet |
Antarctic The Antarctic East Antarctica |
genre |
Antarc* Antarctic Antarctica East Antarctica The Cryosphere |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica The Cryosphere |
op_source |
ISSN: 1994-0424 EISSN: 1994-0416 The Cryosphere https://hal.archives-ouvertes.fr/hal-01806796 The Cryosphere, Copernicus 2018, 12 (1), pp.169 - 187. ⟨10.5194/tc-12-169-2018⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/tc-12-169-2018 hal-01806796 https://hal.archives-ouvertes.fr/hal-01806796 https://hal.archives-ouvertes.fr/hal-01806796/document https://hal.archives-ouvertes.fr/hal-01806796/file/tc-12-169-2018.pdf doi:10.5194/tc-12-169-2018 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.5194/tc-12-169-2018 |
container_title |
The Cryosphere |
container_volume |
12 |
container_issue |
1 |
container_start_page |
169 |
op_container_end_page |
187 |
_version_ |
1766264145283383296 |
spelling |
ftunivnantes:oai:HAL:hal-01806796v1 2023-05-15T13:56:36+02:00 On the similarity and apparent cycles of isotopic variations in East Antarctic snow pits Laepple, Thomas Munch, Thomas Casado, Mathieu Hoerhold, Maria Landais, Amaelle Kipfstuhl, Sepp Alfred Wegener Institute Potsdam Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI) Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE) Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) Climate Sciences Department Bremerhaven Glaces et Continents, Climats et Isotopes Stables (GLACCIOS) Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) 2018 https://hal.archives-ouvertes.fr/hal-01806796 https://hal.archives-ouvertes.fr/hal-01806796/document https://hal.archives-ouvertes.fr/hal-01806796/file/tc-12-169-2018.pdf https://doi.org/10.5194/tc-12-169-2018 en eng HAL CCSD Copernicus info:eu-repo/semantics/altIdentifier/doi/10.5194/tc-12-169-2018 hal-01806796 https://hal.archives-ouvertes.fr/hal-01806796 https://hal.archives-ouvertes.fr/hal-01806796/document https://hal.archives-ouvertes.fr/hal-01806796/file/tc-12-169-2018.pdf doi:10.5194/tc-12-169-2018 info:eu-repo/semantics/OpenAccess ISSN: 1994-0424 EISSN: 1994-0416 The Cryosphere https://hal.archives-ouvertes.fr/hal-01806796 The Cryosphere, Copernicus 2018, 12 (1), pp.169 - 187. ⟨10.5194/tc-12-169-2018⟩ [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology info:eu-repo/semantics/article Journal articles 2018 ftunivnantes https://doi.org/10.5194/tc-12-169-2018 2022-10-18T23:40:08Z International audience Stable isotope ratios δ 18 O and δD in polar ice provide a wealth of information about past climate evolution. Snow-pit studies allow us to relate observed weather and climate conditions to the measured isotope variations in the snow. They therefore offer the possibility to test our understanding of how isotope signals are formed and stored in firn and ice. As δ 18 O and δD in the snowfall are strongly correlated to air temperature, isotopes in the near-surface snow are thought to record the seasonal cycle at a given site. Accordingly , the number of seasonal cycles observed over a given depth should depend on the accumulation rate of snow. However , snow-pit studies from different accumulation conditions in East Antarctica reported similar isotopic variability and comparable apparent cycles in the δ 18 O and δD profiles with typical wavelengths of ∼ 20 cm. These observations are unexpected as the accumulation rates strongly differ between the sites, ranging from 20 to 80 mm w.e. yr −1 (∼ 6-21 cm of snow per year). Various mechanisms have been proposed to explain the isotopic variations individually at each site; however , none of these are consistent with the similarity of the different profiles independent of the local accumulation conditions. Here, we systematically analyse the properties and origins of δ 18 O and δD variations in high-resolution firn profiles from eight East Antarctic sites. First, we confirm the suggested cycle length (mean distance between peaks) of ∼ 20 cm by counting the isotopic maxima. Spectral analysis further shows a strong similarity between the sites but indicates no dominant periodic features. Furthermore, the apparent cycle length increases with depth for most East Antarctic sites, which is inconsistent with burial and compression of a regular seasonal cycle. We show that these results can be explained by isotopic diffusion acting on a noise-dominated isotope signal. The firn diffusion length is rather stable across the Antarctic Plateau and thus leads to ... Article in Journal/Newspaper Antarc* Antarctic Antarctica East Antarctica The Cryosphere Université de Nantes: HAL-UNIV-NANTES Antarctic The Antarctic East Antarctica The Cryosphere 12 1 169 187 |