These data include results from 11 different oceanic surveys for a total of 41 expedition legs. Collectively, they represent a globally distributed sampling that includes locations in the Atlantic, Pacific, Indian, and Southern Oceans, as well as the Mediterranean and Red Seas. The measurements were made by an automated high-precision shipboard gas chromatographic system developed during the late 1970s and used extensively over the intervening years. This instrument measures CO 2 by flame iozionation after quantitative reaction to methane in a stream of hydrogen.
Nitrous oxide is measured by a separate electron capture detector.
These data constitute one of the most extensive records available of CO 2 and, particularly, N 2 O in marine air and surface seawater. The data will be valuable in modeling applications dealing with the ocean's role in the global cycles of carbon and nitrogen, in studies of ocean-atmospheric dynamics, and in studies evaluating other methodologies for determining pCO 2 . All data have been assessed for quality and consistency and have been edited to remove serious outliers and contaminated samples and to correct gross numerical errors.