Exhaustive modelling study of the oceanic neodymium parameters
Exploring global marine neodymium (Nd) cycling and the interplay between climatic and oceanographic conditions under both modern and palaeoceanographic contexts stands among the important GEOTRACES objectives. This goal requires state of the art modelling and a solid data base, which is proposed in this study: an updated compilation of neodymium parameters comprising 6048 Nd concentrations and 3278 εNd data allowed Robinson and co-authors to implement the neodymium isotopes (143Nd and 144Nd) into the ocean model of the FAMOUS general circulation model (Nd v1.0). Aeolian dust, riverine fluxes, and sedimentary release represent the major interfaces and sources of Nd to the ocean, with reversible scavenging onto biogenic and lithogenic particles coupled with physical ocean circulation governing internal marine Nd cycling. All these sources, sinks and internal processes are tested in Robinson’s modelling exercise. Her conclusion reinforces the important role of the solid particles in driving the Nd oceanic cycle, be they sinking through the water column or sedimented, as seafloor source. However, model-data mismatch in the North Pacific and northern North Atlantic Oceans suggest that certain reactive components of the sediment interact the most with seawater. These results are important for interpreting Nd isotopes in terms of ocean circulation.
Robinson, S., Ivanovic, R., Gregoire, L., Tindall, J., van de Flierdt, T., Plancherel, Y., Pöppelmeier, F., Tachikawa, K., & Valdes, P. (2022). Simulating marine neodymium isotope distributions using ND v1.0 coupled to the ocean component of the FAMOUS-MOSES1 climate model: sensitivities to reversible scavenging efficiency and benthic source distributions. Access the paper:10.5194/egusphere-2022-606