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| Titel |
Toward an integrated ice core chronology using relative and orbital tie-points |
| VerfasserIn |
L. Bazin, A. Landais, B. Lemieux-Dudon, H. Toye Mahamadou Kele, T. Blunier, E. Capron, J. Chappellaz, H. Fischer, M. Leuenberger, V. Lipenkov, M.-F. Loutre, P. Martinerie, F. Parrenin, F. Prié, D. Raynaud, D. Veres, E. Wolff |
| Konferenz |
EGU General Assembly 2012
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250065446
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| Zusammenfassung |
| Precise ice cores chronologies are essential to better understand the mechanisms linking
climate change to orbital and greenhouse gases concentration forcing. A tool for ice core
dating (DATICE [developed by Lemieux-Dudon et al., 2010] permits to generate a common
time-scale integrating relative and absolute dating constraints on different ice cores, using
an inverse method. Nevertheless, this method has only been applied for a 4-ice
cores scenario and for the 0-50 kyr time period. Here, we present the bases for an
extension of this work back to 800 ka using (1) a compilation of published and new
relative and orbital tie-points obtained from measurements of air trapped in ice
cores and (2) an adaptation of the DATICE inputs to 5 ice cores for the last 800
ka.
We first present new measurements of δ18Oatm and δO2/N2 on the Talos Dome and EPICA
Dome C (EDC) ice cores with a particular focus on Marine Isotopic Stages (MIS) 5, and 11.
Then, we show two tie-points compilations. The first one is based on new and published CH4
and δ18Oatm measurements on 5 ice cores (NorthGRIP, EPICA Dronning Maud Land,
EDC, Talos Dome and Vostok) in order to produce a table of relative gas tie-points
over the last 400 ka. The second one is based on new and published records of
δO2/N2, δ18Oatm and air content to provide a table of orbital tie-points over the last
800 ka. Finally, we integrate the different dating constraints presented above in
the DATICE tool adapted to 5 ice cores to cover the last 800 ka and show how
these constraints compare with the established gas chronologies of each ice core. |
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