Water samples were collected using Niskin bottles at six oceanographic stations in the northeast Pacific, from Station ALOHA to Resurrection Bay, during cruise CDisK-IV, on board RV Kilo Moana in August 2017. Surface water samples were collected from the ship's underway water system. The samples were filtered through Millipore polyethersulfone (PES) syringe filters into acid clean low-density polyethylene (LDPE) bottles, and acidified with HNO3 to final acid concentration of 0.02-0.4 M. Strontium concentrations were analysed at GEOMAR Helmholtz Centre for Ocean Research Kiel using an Element-XR high resolution sector field inductively coupled plasma mass spectrometer (HR-ICP-MS) in medium resolution (M=4000), after dilution at a 1:20 ratio with 1 M HNO3. The analyses were calibrated by standard additions of single element barium solutions into a surface water sample from the subtropical North Atlantic. Strontium concentrations were analysed at the University of Cambridge as Sr/Na ratios using an Agilent Technologies 5100 inductively coupled plasma optical emission spectroscopy (ICP-OES), using sample-standard bracketing. An IAPSO salinity standard that was previously analysed for its strontium concentration was used as the calibration and bracketing standard. Strontium concentrations were normalised to TEOS-10 absolute salinity of 35 g kg−1.