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Abstract. The Global Ocean Data Analysis Project (GLODAP) is a synthesis effort providing regular compilations of surface to bottom ocean biogeochemical bottle data, with an emphasis on seawater inorganic carbon chemistry and related variables determined through chemical analysis of seawater samples. GLODAPv2.2023 is an update of the previous version, GLODAPv2.2022 (Lauvset et al., 2022). The major changes are as follows: data from 23 new cruises were added. In addition, a number of changes were made to the data included in GLODAPv2.2022. GLODAPv2.2023 includes measurements from more than 1.4 million water samples from the global oceans collected on 1108 cruises. The data for the now 13 GLODAP core variables (salinity, oxygen, nitrate, silicate, phosphate, dissolved inorganic carbon, total alkalinity, pH, chlorofluorocarbon-11 (CFC-11), CFC-12, CFC-113, CCl4, and SF6) have undergone extensive quality control with a focus on the systematic evaluation of bias. The data are available in two formats: (i) as submitted by the data originator but converted to World Ocean Circulation Experiment (WOCE) exchange format and (ii) as a merged data product with adjustments applied to minimize bias. For the present annual update, adjustments for the 23 new cruises were derived by comparing those data with the data from the 1085 quality-controlled cruises in the GLODAPv2.2022 data product using crossover analysis. SF6 data from all cruises were evaluated by comparison with CFC-12 data measured on the same cruises. For nutrients and ocean carbon dioxide (CO2), chemistry comparisons to estimates based on empirical algorithms provided additional context for adjustment decisions. The adjustments that we applied are intended to remove potential biases from errors related to measurement, calibration, and data-handling practices without removing known or likely time trends or variations in the variables evaluated. The compiled and adjusted data product is believed to be consistent to better than 0.005 in salinity, 1 % in oxygen, 2 % in nitrate, 2 % in silicate, 2 % in phosphate, 4 µmol kg−1 in dissolved inorganic carbon, 4 µmol kg−1 in total alkalinity, 0.01–0.02 in pH (depending on region), and 5 % in the halogenated transient tracers. The other variables included in the compilation, such as isotopic tracers and discrete CO2 fugacity (fCO2), were not subjected to bias comparison or adjustments. The original data, their documentation, and DOI codes are available at the Ocean Carbon and Acidification Data System of NOAA National Centers for Environmental Information (NCEI), which also provides access to the merged data product. This is provided as a single global file and as four regional ones – the Arctic, Atlantic, Indian, and Pacific oceans – under https://doi.org/10.25921/zyrq-ht66 (Lauvset et al., 2023). These bias-adjusted product files also include significant ancillary and approximated data, which were obtained by interpolation of, or calculation from, measured data. This living data update documents the GLODAPv2.2023 methods and provides a broad overview of the secondary quality control procedures and results. 

Abstract. The Global Ocean Data Analysis Project (GLODAP) is asynthesis effort providing regular compilations of surface-to-bottom oceanbiogeochemical bottle data, with an emphasis on seawater inorganic carbonchemistry and related variables determined through chemical analysis ofseawater samples. GLODAPv2.2022 is an update of the previous version,GLODAPv2.2021 (Lauvset et al., 2021). The major changes are as follows: datafrom 96 new cruises were added, data coverage was extended until 2021, andfor the first time we performed secondary quality control on all sulfurhexafluoride (SF6) data. In addition, a number of changes were made todata included in GLODAPv2.2021. These changes affect specifically theSF6 data, which are now subjected to secondary quality control, andcarbon data measured on board the RV Knorr in the Indian Ocean in 1994–1995 whichare now adjusted using certified reference material (CRM) measurements made at the time. GLODAPv2.2022includes measurements from almost 1.4 million water samples from the globaloceans collected on 1085 cruises. The data for the now 13 GLODAP corevariables (salinity, oxygen, nitrate, silicate, phosphate, dissolvedinorganic carbon, total alkalinity, pH, chlorofluorocarbon-11 (CFC-11), CFC-12, CFC-113, CCl4,and SF6) have undergone extensive quality control with a focus onsystematic evaluation of bias. The data are available in two formats: (i) assubmitted by the data originator but converted to World Ocean CirculationExperiment (WOCE) exchange format and (ii) as a merged data product withadjustments applied to minimize bias. For the present annual update,adjustments for the 96 new cruises were derived by comparing those data withthe data from the 989 quality-controlled cruises in the GLODAPv2.2021 dataproduct using crossover analysis. SF6 data from all cruises wereevaluated by comparison with CFC-12 data measured on the same cruises. Fornutrients and ocean carbon dioxide (CO2) chemistry comparisons toestimates based on empirical algorithms provided additional context foradjustment decisions. The adjustments that we applied are intended to removepotential biases from errors related to measurement, calibration, and datahandling practices without removing known or likely time trends orvariations in the variables evaluated. The compiled and adjusted dataproduct is believed to be consistent to better than 0.005 in salinity, 1 % in oxygen, 2 % in nitrate, 2 % in silicate, 2 % in phosphate,4 µmol kg−1 in dissolved inorganic carbon, 4 µmol kg−1in total alkalinity, 0.01–0.02 in pH (depending on region), and 5 % inthe halogenated transient tracers. The other variables included in thecompilation, such as isotopic tracers and discrete CO2 fugacity(fCO2), were not subjected to bias comparison or adjustments. The original data, their documentation, and DOI codes are available at theOcean Carbon and Acidification Data System of NOAA NCEI (https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/GLODAPv2_2022/, last access: 15 August 2022). This site also provides access to themerged data product, which is provided as a single global file and as fourregional ones – the Arctic, Atlantic, Indian, and Pacific oceans –under https://doi.org/10.25921/1f4w-0t92 (Lauvset et al.,2022). These bias-adjusted product files also include significant ancillaryand approximated data, which were obtained by interpolation of, orcalculation from, measured data. This living data update documents theGLODAPv2.2022 methods and provides a broad overview of the secondary qualitycontrol procedures and results.