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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. 

Abstract. The Global Ocean Data Analysis Project (GLODAP) is asynthesis effort providing regular compilations of surface-to-bottom oceanbiogeochemical data, with an emphasis on seawater inorganic carbon chemistryand related variables determined through chemical analysis of seawatersamples. GLODAPv2.2020 is an update of the previous version, GLODAPv2.2019.The major changes are data from 106 new cruises added, extension of timecoverage to 2019, and the inclusion of available (also for historicalcruises) discrete fugacity of CO2 (fCO2) values in the mergedproduct files. GLODAPv2.2020 now includes measurements from more than 1.2 million water samples from the global oceans collected on 946 cruises. Thedata for the 12 GLODAP core variables (salinity, oxygen, nitrate, silicate,phosphate, dissolved inorganic carbon, total alkalinity, pH, CFC-11, CFC-12,CFC-113, and CCl4) have undergone extensive quality control with afocus on systematic evaluation of bias. The data are available in twoformats: (i) as submitted by the data originator but updated to WOCEexchange format and (ii) as a merged data product with adjustments appliedto minimize bias. These adjustments were derived by comparing the data fromthe 106 new cruises with the data from the 840 quality-controlled cruises ofthe GLODAPv2.2019 data product using crossover analysis. Comparisons toempirical algorithm estimates provided additional context for adjustmentdecisions; this is new to this version. The adjustments are intended toremove potential biases from errors related to measurement, calibration, anddata-handling 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 fCO2, were notsubjected to bias comparison or adjustments. The original data and their documentation and DOI codes are available at theOcean Carbon Data System of NOAA NCEI(https://www.nodc.noaa.gov/ocads/oceans/GLODAPv2_2020/, lastaccess: 20 June 2020). This site also provides access to the merged dataproduct, which is provided as a single global file and as four regional ones– the Arctic, Atlantic, Indian, and Pacific oceans –under https://doi.org/10.25921/2c8h-sa89 (Olsen et al., 2020). Thesebias-adjusted product files also include significant ancillary andapproximated data. These were obtained by interpolation of, or calculationfrom, measured data. This living data update documents the GLODAPv2.2020methods and provides a broad overview of the secondary quality controlprocedures and results. 

Abstract. The Global Ocean Data Analysis Project (GLODAP) is asynthesis effort providing regular compilations of surface to bottom oceanbiogeochemical data, with an emphasis on seawater inorganic carbon chemistryand related variables determined through chemical analysis of water samples.This update of GLODAPv2, v2.2019, adds data from 116 cruises to the previousversion, extending its coverage in time from 2013 to 2017, while also addingsome data from prior years. GLODAPv2.2019 includes measurements from morethan 1.1 million water samples from the global oceans collected on 840cruises. The data for the 12 GLODAP core variables (salinity, oxygen,nitrate, silicate, phosphate, dissolved inorganic carbon, total alkalinity,pH, CFC-11, CFC-12, CFC-113, and CCl4) have undergone extensive qualitycontrol, especially systematic evaluation of bias. The data are available intwo formats: (i) as submitted by the data originator but updated to WOCEexchange format and (ii) as a merged data product with adjustments appliedto minimize bias. These adjustments were derived by comparing the data fromthe 116 new cruises with the data from the 724 quality-controlled cruises ofthe GLODAPv2 data product. They correct for errors related to measurement,calibration, and data handling practices, taking into account any known orlikely time trends or variations. The compiled and adjusted data product isbelieved 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 totalalkalinity, 0.01–0.02 in pH, and 5 % in the halogenated transienttracers. The compilation also includes data for several other variables,such as isotopic tracers. These were not subjected to bias comparison oradjustments. The original data, their documentation and DOI codes are available in theOcean Carbon Data System of NOAA NCEI(https://www.nodc.noaa.gov/ocads/oceans/GLODAPv2_2019/, last access: 17 September 2019). Thissite also provides access to the merged data product, which is provided as asingle global file and as four regional ones – the Arctic, Atlantic, Indian,and Pacific oceans – under https://doi.org/10.25921/xnme-wr20(Olsen et al., 2019). Theproduct files also include significant ancillary and approximated data.These were obtained by interpolation of, or calculation from, measured data.This paper documents the GLODAPv2.2019 methods and provides a broad overviewof the secondary quality control procedures and results.