1. Center for Ocean-Land-Atmosphere Studies, Department of Atmospheric, Oceanic, and Earth Sciences, George Mason University, Fairfax, VA 22030, USA.
2. Department of Geology and Geophysics, Yale University, New Haven, CT 06511, USA.
3. Department of Geosciences, Princeton University, Princeton, NJ 08544, USA.
4. Institute of Geological Sciences and Oeschger Center for Climate Change Research, University of Bern, Bern, Switzerland.
5. Alfred Wegener Institute, Bremerhaven, Germany.
6. Department of Climate Geochemistry, Max-Planck Institute for Chemistry, Mainz, Germany.
7. Geological Institute, Department of Earth Sciences, ETH Zürich, Switzerland.