Dissolved neodymium (Nd) isotope compositions and rare earth element (REE) concentrations along with stable oxygen isotope compositions measured on water bottle samples collected during PU2014 to the Barents Sea in 2014

Nearly half the inflow of warm and saline Atlantic Water (AW) to the Arctic Ocean is substantially cooled and freshened in the Barents Sea, which is therefore considered a key region for water mass transformation in the Arctic Mediterranean. Numerous studies have focused on this transformation and the increasing influence of AW on Arctic climate and biodiversity, yet geochemical investigations of these processes have been scarce. Using the first comprehensive data set of the distributions of dissolved radiogenic neodymium (Nd) isotopes (expressed as ɛNd), rare earth elements (REE) and stable oxygen isotope (δ18O) compositions from this region we are able to constrain the transport and transformation of AW in the Barents Sea and to investigate which processes change the chemical composition of the water masses beyond what is expected from circulation and mixing.