GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany; Department of Geosciences, University of Oslo, Oslo, Norway; Max Planck Institute for Meteorology, Hamburg, Germany; Laboratory of Environmental Chemistry, Paul Scherrer Institute, Villigen, Switzerland; Oeschger Centre for Climate Change Research, Bern, Switzerland; Climate Change Impacts and Risks in the Anthropocene (C-CIA), Institute for Environmental Sciences, University of Geneva, Geneva, Switzerland; dendrolab.ch, Department of Earth Sciences, University of Geneva, Geneva, Switzerland; Department F.-A. Forel for Aquatic and Environmental Sciences, University of Geneva, Geneva, Switzerland; School of Earth and Environmental Sciences, University of St Andrews, Fife, United Kingdom; Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, United States