Hydrological parameters, nutrient and trace metal concentrations measured along GEOTRACES transects DP18 and GP02 (North Pacific) in 2011-2012 and GEOTRACES Japan reconnaissance study along 160°W, 10°S–54°N in 2005

This data contains the basic hydrological parameters, including temperature, salinity, potential density anomaly, potential temperature, dissolved oxygen, silicate, nitrate, phosphate, ammonium, and chlorophyll-a concentrations, dissolved (d) Cd, dNi, dZn, dCu, and labile particulate Cu concentrations in the North Pacific Ocean along the GEOTRACES transects GP18 (165°E) and GP02 (47°N), and along 160°W. Samples (~125 g) used to determine the total dissolvable trace metals (tdMs) were unfiltered and acidified to pH 2.2 using ultrapure HCl (Tamapure AA-10, Tama Chemicals) immediately after collection. Portions of collected seawater samples were filtered onboard using 0.2 µm filters to acquire the dM samples. Nuclepore polycarbonate membrane filters (Whatman) were used for the KH-05-2 and KH-11-7 cruises, whilst during the KH-12-4 cruise, AcroPak capsule filters (Pall) were utilized. These filtered seawater samples were also acidified to pH 2.2 with ultrapure HCl. Seawater samples were stored at room temperature for at least one year prior to analysis.An offline automated solid-phase extraction system (SPE-100, Hiranuma Sangyo) with a column of Nobias Chelate-PA1 resin (Hitachi High-Technologies) was used to preconcentrate the trace metals (Al, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb) in seawater (Minami et al., 2015; doi:10.1016/j.aca.2014.11.016). Trace metals were measured by high-resolution inductively coupled plasma mass spectrometer (HR-ICP-MS, Element 2, Thermo Fisher Scientific), using calibration curve method. Temperature (with a precision of 0.001 °C) was measured with CTD, and salinity was measured by using a salinometer (Autosal 8400B, Ocean Scientific International Ltd., Havant, UK). An auto analyzer (SWAAT, BLTEC, Osaka, Japan) was used for nutrient analysis (NO3, NO2, Si(OH)4, and PO4), and Chl. a was determined by using a fluorometric method (Welschmeyer 1994; doi:10.4319/lo.1994.39.8.1985).