Tab. 1: Sampling date, location, ice thickness, salinity, Nd isotope compositions and REE concentrations for the sea-ice samples recovered during cruise PS80

• Main Authors: Laukert, Georgi, Frank, Martin, Hathorne, Ed C, Krumpen, Thomas, Rabe, Ben, Bauch, Dorothea, Werner, Kirstin, Peeken, Ilka, Kassens, Heidemarie
• Format: Dataset
• Language: English
• Published: PANGAEA 2017
• Subjects: Arctic Ocean; ARK-XXVII/3; AWI_SeaIce; Cerium; dissolved; CTD/Rosette; CTD-RO; Date/Time of event; Dysprosium; Erbium; Europium; Event label; Gadolinium; GEOMAR; Heavy rare-earth elements/Light rare-earth elements ratio; Helmholtz Centre for Ocean Research Kiel; Holmium; ICE; Ice station; Ice station #3; Ice station #4; Ice station #8; incl. ice station; Lanthanum; Latitude of event; Longitude of event; Lutetium; Neodymium; Neodymium-143/Neodymium-144 ratio; Normalized; Optional event label; Polarstern; Praseodymium; PS80/255-1; PS80/277-1; PS80/336-1; PS80/360-1; PS80 IceArc; Salinity; Samarium; Arctic; Fram Strait; lena river; Polarforschung; Sea ice
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.883658; https://doi.org/10.1594/PANGAEA.883658

Freshwater and sea ice in the Arctic Ocean (AO) both respond to climate forcing but changes in their distribution may in turn also significantly affect Northern Hemisphere climate. The exact mechanisms controlling their transport are, however, still subject of ongoing research. Radiogenic neodymium (Nd) isotopes (expressed as eNd) and rare earth elements (REEs) have successfully been used to trace ocean circulation in the AO and can provide valuable information on the origin, transport and fate of Arctic freshwater and drifting sea ice. Here, we present first sea-ice data and discuss the applicability of these tracers to determine the pathways of Siberian freshwater and the source areas of Arctic sea ice within the Eurasian Basin. Freshwaters originating from various Siberian rivers are well mixed and diluted prior to their advection to the central AO and the Fram Strait, thereby inhibiting the assessment of the individual contributions of the different rivers for these regions. Recent investigations of seawater Nd isotope and REE distributions on the Siberian shelves now allow for a more detailed determination of the sources of transpolar freshwater transport, and suggest that freshwater from the Lena River can at least be qualitatively traced further away from the shelves. In addition, sea ice has the potential to preserve marine and riverine eNd and REE signatures of the Siberian shelf source waters transported across the AO to the Fram Strait thereby avoiding the effects of mixing. Here, we test this potential for the first time by comparing eNd and REE signatures determined from unfiltered but essentially sediment-free sea-ice samples recovered in the Eurasian Basin of the central AO in 2012 with corresponding signatures of surface seawater in the formation regions of the ice. The sampled sea ice is dominantly characterized by ?Nd values near -8, in agreement with the incorporation of radiogenic freshwater (eNd=-6) from the Yenisei and Ob rivers and its formation east of Vilkitsky Strait as identified by a ...