1Fondazione Centro Euro-Mediterraneo sui Cambiamenti Climatici, 40129 Bologna, Italy
2Istituto Nazionale di Oceanografia Sperimentale, 34010 Sgonico, Italy
3Department of Geology, Colorado College, Colorado Springs, CO 80903 USA
4Centro Nazionale delle Ricerche - Istituto di Scienze Marine, 30122 Venice, Italy
5Antarctic Research Centre, Victoria University of Wellington, Wellington, 6140 New Zealand
6GNS Science, Avalon, Lower Hutt, 5010 New Zealand
7Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, 27570 Bremerhaven, Germany
8University of Bremen, 28359 Bremen, Germany
9Department of Earth and Environmental Studies, Center for Environmental and Life Sciences, Montclair State University, Montclair, NY 07043 USA
10Grantham Institute and Department of Earth Science and Engineering, Imperial College of London, London, SW7 2AZ UK
© The Author(s) 2018
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