Sub-millennial climate variability during MIS 11 revealed by high resolution EPICA Dome C isotopic data – a comparison with the Holocene
1Laboratoire des Sciences du Climat et de l'Environnement, IPSL, CEA CNRS UVSQ UMR 8212, CEA Saclay, L'Orme-des-Merisiers, 91191 Gif-Sur-Yvette Cedex, France
2Laboratoire De Morphodynamique Continentale et Côtière – UMR CNRS 6143, Bât IRESE A, Département de Géologie, Université de Rouen, 76821 Mont Saint Aignan Cedex, France
3Department of Geosciences, Princeton University, Princeton, NJ, USA
4Centre for Ice and Climate, Niels Bohr Institue, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen, Denmark
5Università di Trieste, Dipartimento di Scienze Geologiche, Ambientali e Marine, Via E. Weiss 2, 34127 Trieste, Italy
Abstract. We expand here the description of the Antarctic temperature variability during the long interglacial period occurring ~400 thousand years before present (Marine Isotopic Stage, MIS 11). This is achieved thanks to new detailed deuterium measurements conducted on the EPICA Dome C ice core, Antarctica, with a ~50 year temporal resolution. Despite an ice diffusion length reaching ~8 cm at MIS 11 depth, the data allow to highlight a variability at multi-centennial scale for MIS 11, as it has already been observed for the Holocene (MIS 1). Differences between MIS 1 and MIS 11 are analysed regarding the links between multi-millennial trends and sub-millennial variability. The EPICA Dome C deuterium record shows an increased variability and a shift in the observed periodicities at the onset of the final cooling phase of MIS 11, with stronger millennial to multi-millennial variability. Our findings are robust with respect to sensitivity tests on the somewhat uncertain MIS 11 duration.