Dissolved neodymium isotopic composition, rare earth element and trace metal concentrations of surface water in the South Pacific Ocean from the SONNE cruise SO289 (GEOTRACES cruise GP21)

This dataset contains dissolved radiogenic neodymium (Nd) isotopes, rare earth element (REE) and trace metal (TM) concentrations of surface water in the South Pacific Ocean collected during the cross-Pacific GEOTRACES GP21 expedition (Chile-New Caledonia) with the German research vessel SONNE (SO289), which took place between February 23 and April 4, 2022. 20-40 L of surface seawater was collected either from the Niskin bottles attached to a stainless steel CTD rosette or from a trace-metal-clean underway tow-fish for Nd isotopes and REE concentrations. TM samples for dissolved manganese (dMn), dissolved iron (dFe), and dissolved aluminum (dAl) were collected from the tow-fish. Samples for Nd isotopes were pre-concentrated onboard by adsorption on Fe hydroxide precipitates and measured with a Neptune Plus Multicollector-Inductively Coupled Plasma Mass Spectrometer (MC-ICP-MS) after purification in the home laboratory. REE concentrations were pre-concentrated offline using a SeaFAST system and analyzed on a Thermo Element XR ICP-MS coupled with a CETAC "Aridus 2" desolvating nebulizer to reduce oxide formation. Dissolved Mn and Fe were pre-concentrated using SeaFast (SC-4 DX; ESI) and then measured on the same Thermo Element XR ICP-MS. Dissolved Al was analyzed shipboard using a Carey Eclipse fluorimeter. Phytoplankton pigment analysis (chlorophyll-a concentrations) were measured using a reverse-phase high-performance liquid chromatography (HPLC) (Dionex UltiMate 3000 LC system, Thermo Scientific).