The Antarctic ice core chronology (AICC2012): an optimized multi-parameter and multi-site dating approach for the last 120 thousand years
The deep polar ice cores provide reference records commonly employed in global correlation of past climate events. However, temporal divergences reaching up to several thousand years (ka) exist between ice cores over the last climatic cycle. In this context, we are hereby introducing the Antarctic I...
Published in: | Climate of the Past |
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Main Authors: | , , , , , , , , , , , , , , , |
Format: | Other/Unknown Material |
Language: | English |
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2018
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Online Access: | https://doi.org/10.5194/cp-9-1733-2013 https://cp.copernicus.org/articles/9/1733/2013/ |
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Copernicus Publications: E-Journals |
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English |
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The deep polar ice cores provide reference records commonly employed in global correlation of past climate events. However, temporal divergences reaching up to several thousand years (ka) exist between ice cores over the last climatic cycle. In this context, we are hereby introducing the Antarctic Ice Core Chronology 2012 (AICC2012), a new and coherent timescale developed for four Antarctic ice cores, namely Vostok, EPICA Dome C (EDC), EPICA Dronning Maud Land (EDML) and Talos Dome (TALDICE), alongside the Greenlandic NGRIP record. The AICC2012 timescale has been constructed using the Bayesian tool Datice (Lemieux-Dudon et al., 2010) that combines glaciological inputs and data constraints, including a wide range of relative and absolute gas and ice stratigraphic markers. We focus here on the last 120 ka, whereas the companion paper by Bazin et al. (2013) focuses on the interval 120–800 ka. Compared to previous timescales, AICC2012 presents an improved timing for the last glacial inception, respecting the glaciological constraints of all analyzed records. Moreover, with the addition of numerous new stratigraphic markers and improved calculation of the lock-in depth (LID) based on δ 15 N data employed as the Datice background scenario, the AICC2012 presents a slightly improved timing for the bipolar sequence of events over Marine Isotope Stage 3 associated with the seesaw mechanism, with maximum differences of about 600 yr with respect to the previous Datice-derived chronology of Lemieux-Dudon et al. (2010), hereafter denoted LD2010. Our improved scenario confirms the regional differences for the millennial scale variability over the last glacial period: while the EDC isotopic record (events of triangular shape) displays peaks roughly at the same time as the NGRIP abrupt isotopic increases, the EDML isotopic record (events characterized by broader peaks or even extended periods of high isotope values) reached the isotopic maximum several centuries before. It is expected that the future contribution of both other long ice core records and other types of chronological constraints to the Datice tool will lead to further refinements in the ice core chronologies beyond the AICC2012 chronology. For the time being however, we recommend that AICC2012 be used as the preferred chronology for the Vostok, EDC, EDML and TALDICE ice core records, both over the last glacial cycle (this study), and beyond (following Bazin et al., 2013). The ages for NGRIP in AICC2012 are virtually identical to those of GICC05 for the last 60.2 ka, whereas the ages beyond are independent of those in GICC05modelext (as in the construction of AICC2012, the GICC05modelext was included only via the background scenarios and not as age markers). As such, where issues of phasing between Antarctic records included in AICC2012 and NGRIP are involved, the NGRIP ages in AICC2012 should therefore be taken to avoid introducing false offsets. However for issues involving only Greenland ice cores, there is not yet a strong basis to recommend superseding GICC05modelext as the recommended age scale for Greenland ice cores. |
format |
Other/Unknown Material |
author |
Veres, D. Bazin, L. Landais, A. Toyé Mahamadou Kele, H. Lemieux-Dudon, B. Parrenin, F. Martinerie, P. Blayo, E. Blunier, T. Capron, E. Chappellaz, J. Rasmussen, S. O. Severi, M. Svensson, A. Vinther, B. Wolff, E. W. |
spellingShingle |
Veres, D. Bazin, L. Landais, A. Toyé Mahamadou Kele, H. Lemieux-Dudon, B. Parrenin, F. Martinerie, P. Blayo, E. Blunier, T. Capron, E. Chappellaz, J. Rasmussen, S. O. Severi, M. Svensson, A. Vinther, B. Wolff, E. W. The Antarctic ice core chronology (AICC2012): an optimized multi-parameter and multi-site dating approach for the last 120 thousand years |
author_facet |
Veres, D. Bazin, L. Landais, A. Toyé Mahamadou Kele, H. Lemieux-Dudon, B. Parrenin, F. Martinerie, P. Blayo, E. Blunier, T. Capron, E. Chappellaz, J. Rasmussen, S. O. Severi, M. Svensson, A. Vinther, B. Wolff, E. W. |
author_sort |
Veres, D. |
title |
The Antarctic ice core chronology (AICC2012): an optimized multi-parameter and multi-site dating approach for the last 120 thousand years |
title_short |
The Antarctic ice core chronology (AICC2012): an optimized multi-parameter and multi-site dating approach for the last 120 thousand years |
title_full |
The Antarctic ice core chronology (AICC2012): an optimized multi-parameter and multi-site dating approach for the last 120 thousand years |
title_fullStr |
The Antarctic ice core chronology (AICC2012): an optimized multi-parameter and multi-site dating approach for the last 120 thousand years |
title_full_unstemmed |
The Antarctic ice core chronology (AICC2012): an optimized multi-parameter and multi-site dating approach for the last 120 thousand years |
title_sort |
antarctic ice core chronology (aicc2012): an optimized multi-parameter and multi-site dating approach for the last 120 thousand years |
publishDate |
2018 |
url |
https://doi.org/10.5194/cp-9-1733-2013 https://cp.copernicus.org/articles/9/1733/2013/ |
long_lat |
ENVELOPE(158.000,158.000,-73.000,-73.000) |
geographic |
Antarctic Dronning Maud Land Greenland Talos Dome The Antarctic |
geographic_facet |
Antarctic Dronning Maud Land Greenland Talos Dome The Antarctic |
genre |
Antarc* Antarctic Dronning Maud Land EPICA Greenland Greenland ice cores greenlandic ice core NGRIP |
genre_facet |
Antarc* Antarctic Dronning Maud Land EPICA Greenland Greenland ice cores greenlandic ice core NGRIP |
op_source |
eISSN: 1814-9332 |
op_relation |
info:eu-repo/grantAgreement/EC/FP7/243908 doi:10.5194/cp-9-1733-2013 https://cp.copernicus.org/articles/9/1733/2013/ |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/cp-9-1733-2013 |
container_title |
Climate of the Past |
container_volume |
9 |
container_issue |
4 |
container_start_page |
1733 |
op_container_end_page |
1748 |
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1766260376970723328 |
spelling |
ftcopernicus:oai:publications.copernicus.org:cp17907 2023-05-15T13:54:27+02:00 The Antarctic ice core chronology (AICC2012): an optimized multi-parameter and multi-site dating approach for the last 120 thousand years Veres, D. Bazin, L. Landais, A. Toyé Mahamadou Kele, H. Lemieux-Dudon, B. Parrenin, F. Martinerie, P. Blayo, E. Blunier, T. Capron, E. Chappellaz, J. Rasmussen, S. O. Severi, M. Svensson, A. Vinther, B. Wolff, E. W. 2018-09-27 info:eu-repo/semantics/application/pdf https://doi.org/10.5194/cp-9-1733-2013 https://cp.copernicus.org/articles/9/1733/2013/ eng eng info:eu-repo/grantAgreement/EC/FP7/243908 doi:10.5194/cp-9-1733-2013 https://cp.copernicus.org/articles/9/1733/2013/ info:eu-repo/semantics/openAccess eISSN: 1814-9332 info:eu-repo/semantics/Text 2018 ftcopernicus https://doi.org/10.5194/cp-9-1733-2013 2020-07-20T16:25:24Z The deep polar ice cores provide reference records commonly employed in global correlation of past climate events. However, temporal divergences reaching up to several thousand years (ka) exist between ice cores over the last climatic cycle. In this context, we are hereby introducing the Antarctic Ice Core Chronology 2012 (AICC2012), a new and coherent timescale developed for four Antarctic ice cores, namely Vostok, EPICA Dome C (EDC), EPICA Dronning Maud Land (EDML) and Talos Dome (TALDICE), alongside the Greenlandic NGRIP record. The AICC2012 timescale has been constructed using the Bayesian tool Datice (Lemieux-Dudon et al., 2010) that combines glaciological inputs and data constraints, including a wide range of relative and absolute gas and ice stratigraphic markers. We focus here on the last 120 ka, whereas the companion paper by Bazin et al. (2013) focuses on the interval 120–800 ka. Compared to previous timescales, AICC2012 presents an improved timing for the last glacial inception, respecting the glaciological constraints of all analyzed records. Moreover, with the addition of numerous new stratigraphic markers and improved calculation of the lock-in depth (LID) based on δ 15 N data employed as the Datice background scenario, the AICC2012 presents a slightly improved timing for the bipolar sequence of events over Marine Isotope Stage 3 associated with the seesaw mechanism, with maximum differences of about 600 yr with respect to the previous Datice-derived chronology of Lemieux-Dudon et al. (2010), hereafter denoted LD2010. Our improved scenario confirms the regional differences for the millennial scale variability over the last glacial period: while the EDC isotopic record (events of triangular shape) displays peaks roughly at the same time as the NGRIP abrupt isotopic increases, the EDML isotopic record (events characterized by broader peaks or even extended periods of high isotope values) reached the isotopic maximum several centuries before. It is expected that the future contribution of both other long ice core records and other types of chronological constraints to the Datice tool will lead to further refinements in the ice core chronologies beyond the AICC2012 chronology. For the time being however, we recommend that AICC2012 be used as the preferred chronology for the Vostok, EDC, EDML and TALDICE ice core records, both over the last glacial cycle (this study), and beyond (following Bazin et al., 2013). The ages for NGRIP in AICC2012 are virtually identical to those of GICC05 for the last 60.2 ka, whereas the ages beyond are independent of those in GICC05modelext (as in the construction of AICC2012, the GICC05modelext was included only via the background scenarios and not as age markers). As such, where issues of phasing between Antarctic records included in AICC2012 and NGRIP are involved, the NGRIP ages in AICC2012 should therefore be taken to avoid introducing false offsets. However for issues involving only Greenland ice cores, there is not yet a strong basis to recommend superseding GICC05modelext as the recommended age scale for Greenland ice cores. Other/Unknown Material Antarc* Antarctic Dronning Maud Land EPICA Greenland Greenland ice cores greenlandic ice core NGRIP Copernicus Publications: E-Journals Antarctic Dronning Maud Land Greenland Talos Dome ENVELOPE(158.000,158.000,-73.000,-73.000) The Antarctic Climate of the Past 9 4 1733 1748 |