10.1594/PANGAEA.824894
Bazin, Lucie
Lucie
Bazin
0000-0003-4808-4090
Landais, Amaëlle
Amaëlle
Landais
0000-0002-5620-5465
Lemieux-Dudon, Bénédicte
Bénédicte
Lemieux-Dudon
Toyé Mahamadou Kele, H
H
Toyé Mahamadou Kele
Veres, Daniel
Daniel
Veres
0000-0003-3932-577X
Parrenin, Frédéric
Frédéric
Parrenin
0000-0002-9489-3991
Martinerie, Patricia
Patricia
Martinerie
0000-0002-6820-2296
Ritz, Catherine
Catherine
Ritz
0000-0003-0785-8571
Capron, Emilie
Emilie
Capron
0000-0003-0784-1884
Lipenkov, Vladimir Ya
Vladimir Ya
Lipenkov
0000-0003-4221-5440
Loutre, Marie-France
Marie-France
Loutre
0000-0001-6944-4038
Raynaud, Dominique
Dominique
Raynaud
Vinther, Bo Møllesøe
Bo Møllesøe
Vinther
0000-0002-6078-771X
Svensson, Anders M
Anders M
Svensson
0000-0002-4364-6085
Rasmussen, Sune Olander
Sune Olander
Rasmussen
0000-0002-4177-3611
Severi, Mirko
Mirko
Severi
0000-0003-1511-6762
Blunier, Thomas
Thomas
Blunier
0000-0002-6065-7747
Leuenberger, Markus Christian
Markus Christian
Leuenberger
0000-0003-4299-6793
Fischer, Hubertus
Hubertus
Fischer
0000-0002-2787-4221
Masson-Delmotte, Valerie
Valerie
Masson-Delmotte
Chappellaz, Jérôme A
Jérôme A
Chappellaz
Wolff, Eric William
Eric William
Wolff
0000-0002-5914-8531
The Antarctic ice core chronology (AICC2012)
PANGAEA
2013
European Project for Ice Coring in Antarctica (EPICA)
Greenland Ice Core Projects (GRIP/GISP/NGRIP)
1980-01-01T00:00:00/2008-12-31T00:00:00
Publication Series of Datasets
10.5194/cp-9-1715-2013
10.5194/cp-9-1733-2013
16 datasets
application/zip
Creative Commons Attribution 3.0 Unported
Abstract of Bazin et al. (2013): An accurate and coherent chronological framework is essential for the interpretation of climatic and environmental records obtained from deep polar ice cores. Until now, one common ice core age scale had been developed based on an inverse dating method (Datice), combining glaciological modelling with absolute and stratigraphic markers between 4 ice cores covering the last 50 ka (thousands of years before present) (Lemieux-Dudon et al., 2010). In this paper, together with the companion paper of Veres et al. (2013), we present an extension of this work back to 800 ka for the NGRIP, TALDICE, EDML, Vostok and EDC ice cores using an improved version of the Datice tool. The AICC2012 (Antarctic Ice Core Chronology 2012) chronology includes numerous new gas and ice stratigraphic links as well as improved evaluation of background and associated variance scenarios. This paper concentrates on the long timescales between 120-800 ka. In this framework, new measurements of d18Oatm over Marine Isotope Stage (MIS) 11-12 on EDC and a complete d18Oatm record of the TALDICE ice cores permit us to derive additional orbital gas age constraints. The coherency of the different orbitally deduced ages (from d18Oatm, dO2/N2 and air content) has been verified before implementation in AICC2012. The new chronology is now independent of other archives and shows only small differences, most of the time within the original uncertainty range calculated by Datice, when compared with the previous ice core reference age scale EDC3, the Dome F chronology, or using a comparison between speleothems and methane. For instance, the largest deviation between AICC2012 and EDC3 (5.4 ka) is obtained around MIS 12. Despite significant modifications of the chronological constraints around MIS 5, now independent of speleothem records in AICC2012, the date of Termination II is very close to the EDC3 one.
Abstract of Veres et al. (2013): 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 d15N 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.
The AICC2012 chronology is a common and precise chronology for Vostok, EDC, EDML, TALDICE and NGRIP ice core. The new age scale is tuned to GICC05 over the last 60 ka.
This project was funded by the "Fondation de France Ars Cuttoli", the "ANR Citronnier", INRIA and LEFE funding. The research leading to these results has received funding from the European Union's Seventh Framework programme (FP7/2007-2013) under grant agreement no 243908, "Past4Future. Climate change - Learning from the past climate".
-42.32
159.06667
-78.46442
75.1
Fifth Framework Programme
https://doi.org/10.13039/100011104
EVK2-CT-2000-00077
European Project for Ice Coring in Antarctica
Fourth Framework Programme
https://doi.org/10.13039/100011105
ENV4980702
European Project for Ice Coring in Antarctica