Margaux Brandon, Royal Netherlands Institute for Sea Research, Department of Ocean Systems, Den Burg, Netherlands, Dr. Matthew Paul Humphreys, PhD, NIOZ Royal Netherlands Institute for Sea Research, Department of Ocean Systems, Texel, Netherlands, A.C. (Cuun) Koek, University of Groningen, Energy and Sustainability Research Institute Groningen (ESRIG), Centre for Isotope Research (CIO), Groningen, Netherlands, Meike Becker, University of Bergen, Bergen, Norway and Henry C Bittig, Leibniz Institute for Baltic Sea Research, Rostock, Germany