O2/N2 ratios and CO2 mole fractions of air samples collected onbaord cargo ships sailing in the Pacific region

The present data set is data of atmospheric O2/N2 ratios and CO2 mole fractions of flask samples collected onboard cargo ships during regular roundtrip cruises to North America, New Zealand/Australia, and Northeast Asia. Air samples, drawn by a pump from intakes placed on bow mast or at the the top of the bridge of the cargo ships, are forced into Pyrex glass flasks. The collected air samples are sent back to a laboratory in NIES, where O2/N2 ratios and CO2 mole fractions are measured.