The Surface Ocean CO₂ Atlas (SOCAT) is a synthesis activity for quality-controlled, surface ocean fCO₂ (fugacity of carbon dioxide) observations by the international marine carbon research community (>100 contributors). It has over 20 million fCO₂ measurements .
For the Global Ocean Data Analysis Project (GLODAP) extensive quality control and subsequent calibration were carried out for salinity, oxygen, nutrient, carbon dioxide, total alkalinity, pH and chlorofluorocarbon data. Data from approximately one million individual seawater samples were collected from almost 800 cruises carried during the years 1972-2013. The data were used to produce global climatology maps for many of the parameters.