This data set includes measurements of barium concentrations in samples collected during five oceanographic cruises in the Arctic Ocean in 1993. Investigators collected water samples with Niskin, 10-L BIO, and high-density polyethylene (HDPE) bottles. Barium concentrations were determined in the laboratory using isotope-dilution inductively coupled plasma quadrupole mass spectrometry. For detailed information about each cruise, refer to the documentation that accompanies the data files. Data are available via FTP.