[1] Univ Versailles St Quentin Yvelines, CE Saclay, Lab Sci Climat & Environn, Inst Pierre Simon Laplace,CEA,CNRS, F-91191 Gif Sur Yvette, France
[2] Univ Grenoble 1, Lab Glaciol & Geophys Environm, CNRS, F-38402 St Martin Dheres, France
[3] Alfred Wegener Inst Polar & Marine Res, D-27568 Bremerhaven, Germany
[4] Univ Copenhagen, Dept Geophys, DK-2100 Copenhagen, Denmark
[5] Univ Reykjavik, Inst Sci, IS-107 Reykjavik, Iceland
[6] Univ Bern, Inst Phys, CH-3012 Bern, Switzerland
[7] CNRS, Ctr Spectrometrie Nucl & Spectrometrie Masse, F-91405 Orsay, France
[8] Univ Parma, Dept Earth Sci, I-43100 Parma, Italy
[9] Univ Libre Bruxelles, Dept Sci Terre & Environm, Brussels, Belgium
[10] Univ Trieste, Dept Geol Environm & Marine Sci, I-34127 Trieste, Italy
[11] Max Planck Inst Biogeochem, D-7701 Jena, Germany
[12] British Antarctic Survey, Cambridge CB3 0ET, England