Dissolved copper-binding ligands measured in seawater samples from the POLARSTERN cruise PS94 (GEOTRACES GN04)

Copper (Cu) is an important micronutrient involved in different phytoplankton metabolic processes. In seawater, Cu speciation is controlled by the formation of organic complexes with natural binding ligands, which controls its bioavailability and toxicity. The information about Cu organic speciation in the ocean is scarce, particularly in the Arctic Ocean where the ongoing climate change is altering the seawater chemistry. This dataset contains measurements of Cu-binding ligands from station depth profiles sampled between from the Norwegian Coast to the Central Arctic Ocean. Samples were collected during GEOTRACES expedition GN04 (Polarstern cruise PS94) between 17 August and 14 October 2015, following GEOTRACES guidelines (https://www.geotraces.org). The Competitive-Ligand Exchange Adsorptive Cathodic Stripping Voltammetry (CLE-ACSV), using Salicylaldoxime (SA) as competitive ligand (Campos and van den Berg, 1994), was the technique applied to determine the Cu-binding ligand concentrations (LCu) and conditional stability constants (logKcu2+L). The concentration of dissolved copper used for the analysis has been reported by Gerringa et al. (2021) (doi:10.1594/PANGAEA.932797).