These are samples of dissolved barium and stable isotopes of oxygen (d-18O), taken on two cruises in the summers of 2007 and 2008, in collaboration between the NERC-funded Arctic Synoptic Basin-wide Oceanography (ASBO) IPY consortium and the Nansen and Amundsen Basins Observational System (NABOS) program, led by the International Arctic Research Center (IARC), University of Alaska Fairbanks, USA. ... The first cruise, in September 2007, was on R/V Viktor Buynitskiy while the second, in October 2008, was on I/B Kapitan Dranitsyn. The full CTD cast data are available from IARC at http://nabos.iarc.uaf.edu/, while this dataset includes only the CTD-derived temperatures and salinities at the bottle depths, as well as salinities from water samples, where available. The barium samples were analyzed at the College of Oceanic and Atmospheric Sciences, Oregon State University, Corvallis, Oregon, USA, while the oxygen isotopes were analyzed at the NERC Isotope Geosciences Laboratory, British Geological Survey, Keyworth, Nottingham, UK. Inorganic nutrient (nitrate+nitrite, phosphate, and silicate) and dissolved oxygen samples were also taken on these cruises, and will be submitted by the National Oceanography Centre, Southampton, UK.