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,

, We thank the Royal Netherlands Academy of Arts and Sciences (KNAW) for funding and hosting this workshop in Amsterdam, PAGES for their support, and J. Gregory for discussions, This study was supported by the UK-NERC consortium iGlass (NE/I009906/1), and 2012 Australian Laureate Fellowship FL120100050, 2011.

D. J. , E. J. , and P. , thanks the European Research Council for ERC starting grant 259627, and M.H. acknowledges NSF P2C2 grant 0902882. Some of the work was supported by grant 243908, Royal Society Wolfson Research Merit Awards. A.S

A. Contributions, E. J. , A. S. , and H. A. , initiated the PALAEOSENS workshop, and led the drafting of this study together with, The other authors contributed specialist insights, discussions and feedback

, Author Information Reprints and permissions information is available at www.nature.com/reprints. The authors declare no competing financial interests. Readers are welcome to comment on the online version of the paper. Correspondence and requests for materials should be addressed to E, J.R

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