Neodymium isotopes trace marine provenance of Arctic sea ice

• Published in: Geochemical Perspectives Letters
• Main Authors: Laukert, Georgi, Peeken, I., Bauch, Dorothea, Krumpen, T., Hathorne, Ed C., Werner, K., Gutjahr, Marcus, Frank, Martin
• Format: Article in Journal/Newspaper
• Language: English
• Published: European Association of Geochemistry 2022
• Subjects: Arctic; Arctic Ocean; Fram Strait; Sea ice
• Online Access: https://oceanrep.geomar.de/id/eprint/56465/; https://oceanrep.geomar.de/id/eprint/56465/1/Laukert%20et%20al%202022-GPL.pdf; https://oceanrep.geomar.de/id/eprint/56465/2/GPL2220_SIonly.pdf; https://oceanrep.geomar.de/id/eprint/56465/3/GPL2220_TS-1-TS-8.xlsx; https://doi.org/10.7185/geochemlet.2220

Radiogenic neodymium (Nd) isotopes (ɛNd) have the potential to serve as a geochemical tracer of the marine origin of Arctic sea ice. This capability results from pronounced ɛNd differences between the distinct marine and riverine sources, which feed the surface waters from which the ice forms. The first dissolved Nd isotope and rare earth element (REE) concentration data obtained from Arctic sea ice collected across the Fram Strait during RV Polarstern cruise PS85 in 2014 confirm the incorporation and preservation of the parental surface seawater ɛNd signatures despite efficient REE rejection. The large ɛNd variability between ice floes and within sea ice cores (−32 to −10) reflects changes in water mass distribution during ice growth and drift from the central Arctic Ocean to Fram Strait. In addition to the parental seawater composition, our new approach facilitates the reconstruction of the transfer of matter between the atmosphere, the sea ice and the ocean. In conjunction with satellite-derived drift trajectories, we enable a more accurate assessment of sea ice origin and spatiotemporal evolution, benefiting studies of sea ice biology, biodiversity, and biogeochemistry.