gov.noaa.nodc:0164568 eng utf8 dataset NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact HTTPS NOAA Contact Information Information for contacts at NCEI. information custodian 2026-07-27T13:02:55Z ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) Climatological Distributions of pH, pCO2, Total CO2, Alkalinity, and CaCO3 Saturation in the Global Surface Ocean (NCEI Accession 0164568) 2017-08-04 publication 2017-07-31 creation International DOI Foundation (IDF) 10.3334/cdiac/otg.ndp094 NOAA National Centers for Environmental Information gov.noaa.nodc:0164568 NCEI Archive Management System 0164568 NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact HTTPS NCEI Contact Information Information for contacts at NCEI. information publisher Taro Takahashi Lamont-Doherty Earth Observatory (LDEO) http://www.ldeo.columbia.edu/ HTTP Lamont-Doherty Earth Observatory (LDEO) website Institution web page information resourceProvider Lamont-Doherty Earth Observatory (LDEO) http://www.ldeo.columbia.edu/ HTTP Lamont-Doherty Earth Observatory (LDEO) website Institution web page information resourceProvider Takahashi, Taro Columbia University http://www.columbia.edu HTTP Columbia University website Institution web page information author Sutherland, Stewart C. Lamont-Doherty Earth Observatory (LDEO) suth@ldeo.columbia.edu http://www.ldeo.columbia.edu/ HTTP website Institution web page information author Chipman, David W. author Goddard, John G. author Newberger, Timothy University of Colorado Boulder, Cooperative Institute for Research In Environmental Sciences (CIRES) Tim.Newberger@noaa.gov https://cires.colorado.edu/ HTTPS website Institution web page information author Sweeney, Colm NOAA Earth System Research Laboratory https://www.esrl.noaa.gov/ HTTPS NOAA Earth System Research Laboratory (ESRL) website Institution web page information author Lamont-Doherty Earth Observatory (LDEO) http://www.ldeo.columbia.edu/ HTTP Lamont-Doherty Earth Observatory (LDEO) website Institution web page information contributor tableDigital Climatological mean monthly distributions of pH in the total H+ scale, total CO2 concentration (TCO2), and the degree of CaCO3 saturation for the global surface ocean waters (excluding coastal areas) are calculated using a data set for pCO2, alkalinity and nutrient concentrations in surface waters (depths less than 50 m), which is built upon the GLODAP, CARINA and LDEO database. The mutual consistency among these measured parameters is demonstrated using the inorganic carbon chemistry model with the dissociation constants for carbonic acid by Lueker et al. (2000) and for boric acid by Dickson (1990). The global ocean is divided into 24 regions, and the linear potential alkalinity (total alkalinity + nitrate) versus salinity relationships are established for each region. The mean monthly distributions of pH and carbon chemistry parameters for the reference year 2005 are computed using the climatological mean monthly pCO2 data adjusted to a reference year 2005 and the alkalinity estimated from the potential alkalinity versus salinity relationships. The climatological monthly mean values of pCO2 over the global ocean are compiled for a 4° x 5° grid for the reference year 2005, and the gridded data for each of 12 months are included in this database. This is updated version of Takahashi et al. (2009) for the reference year 2000 representing non-El Niño years using a database of about 6.5 million pCO2 data (less coastal areas of North and South America) observed in 1957-2012 (Takahashi et al., 2013). The equatorial zone (4°N-4°S) of the Pacific is excluded from the analysis because of the large interannual changes associated with the El Niño-Southern Oscillation events. The pH thus calculated ranges from 7.9 to 8.2. Lower values are located in the upwelling regions in the tropical Pacific and in the Arabian and Bering Seas; and higher values are found in the subpolar and polar waters during the spring-summer months of intense photosynthetic production. The vast areas of subtropical oceans have seasonally varying pH values ranging from 8.05 during warmer months to 8.15 during colder months. The warm tropical and subtropical waters are supersaturated by a factor of as much as 4.2 with respect to aragonite and 6.3 for calcite, whereas the cold subpolar and polar waters are less supersaturated only by 1.2 for aragonite and 2 for calcite because of the lower pH values resulting from greater TCO2 concentrations. In the western Arctic Ocean, aragonite undersaturation is observed. This dataset is available to the public for a wide variety of uses including scientific research and analysis. completed historicalArchive NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact HTTPS NCEI Contact Information Information for contacts at NCEI. information pointOfContact asNeeded https://www.ncei.noaa.gov/access/metadata/landing-page/bin/gfx?id=gov.noaa.nodc:0164568 Preview graphic PNG 0164568 NCEI ACCESSION NUMBER 2017-07-31 publication ARAGONITE SATURATION STATE CALCITE CONCENTRATION DISSOLVED INORGANIC CARBON (DIC) partial pressure of carbon dioxide - water pH total alkalinity theme NODC DATA TYPES THESAURUS carbon dioxide (CO2) gas analyzer pH sensor showerhead equilibrator titrator instrument NODC INSTRUMENT TYPES THESAURUS chemical physical surface underway theme NODC OBSERVATION TYPES THESAURUS Lamont-Doherty Earth Observatory dataCentre NODC COLLECTING INSTITUTION NAMES THESAURUS Lamont-Doherty Earth Observatory dataCentre NODC SUBMITTING INSTITUTION NAMES THESAURUS Climate Variability and Predictability (CLIVAR) Ship of Opportunity Programme (SOOP) The Global Ocean Ship-based Hydrographic Investigations Program (GO-SHIP) World Ocean Circulation Experiment (WOCE) project NODC PROJECT NAMES THESAURUS Indian Ocean North Atlantic Ocean North Pacific Ocean South Atlantic Ocean South Pacific Ocean place NODC SEA AREA NAMES THESAURUS oceanography theme WMO_CategoryCode 2012-09-15 publication COLUMBIA/LDEO > Lamont-Doherty Earth Observatory, Columbia University dataCentre Global Change Master Directory (GCMD) Data Center Keywords 2026 revision 24 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian CLIVAR > Climate Variability WOCE > World Ocean Circulation Experiment project Global Change Master Directory (GCMD) Project Keywords 2026 revision 24 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian Ocean Carbon Data System (OCADS) Project project Ocean Acidification Search Keywords EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > ALKALINITY EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > CARBON DIOXIDE EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > CARBONATE EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > INORGANIC CARBON EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > PH theme Global Change Master Directory (GCMD) Science Keywords 2026 revision 24 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian Climatological Distributions of pH, pCO2, Total CO2, Alkalinity, and CaCO3 Saturation in the Global Surface Ocean NDP-094 pH, pCO2, Total CO2, Alkalinity, and CaCO3 Saturation theme Originator Keywords CO2 ANALYZERS > CO2 ANALYZERS EQUILIBRATORS PH METERS > PH METERS instrument Global Change Master Directory (GCMD) Instrument Keywords 2026 revision 24 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN OCEAN > ATLANTIC OCEAN > SOUTH ATLANTIC OCEAN OCEAN > INDIAN OCEAN OCEAN > PACIFIC OCEAN > NORTH PACIFIC OCEAN OCEAN > PACIFIC OCEAN > SOUTH PACIFIC OCEAN place Global Change Master Directory (GCMD) Location Keywords 2026 revision 24 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian accessLevel: public otherRestrictions Cite as: Takahashi, Taro; Sutherland, Stewart C.; Chipman, David W.; Goddard, John G.; Newberger, Timothy; Sweeney, Colm (2017). Climatological Distributions of pH, pCO2, Total CO2, Alkalinity, and CaCO3 Saturation in the Global Surface Ocean (NCEI Accession 0164568). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.3334/cdiac/otg.ndp094. Accessed [date]. Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives. otherRestrictions Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose. eng; USA utf8 environment oceans -180 180 -90 90 1957-01-01 2013-12-12 NOAA National Centers for Environmental Information +1-301-713-3277 ncei.info@noaa.gov pointOfContact In most cases, electronic downloads of the data are free. However, fees may apply for custom orders, data certifications, copies of analog materials, and data distribution on physical media. Contact NCEI for other distribution options and instructions. Originator data format 22.34 https://doi.org/10.3334/cdiac/otg.ndp094 HTTPS Web browser NCEI Dataset Landing Page Navigate directly to the URL for a descriptive web page with download links. information https://www.ncei.noaa.gov/archive/accession/oas/164568 HTTPS Web browser Descriptive Information Navigate directly to the URL for a descriptive web page with download links. information https://www.ncei.noaa.gov/archive/accession/download/164568 HTTPS Web browser HTTPS Navigate directly to the URL for data access and direct download. download ftp://ftp-oceans.ncei.noaa.gov/nodc/archive/arc0110/0164568/ FTP Any FTP client FTP These data are available through the File Transfer Protocol (FTP). FTP is no longer supported by most internet browsers. You may copy and paste the FTP link to the data into an FTP client (e.g., FileZilla or WinSCP). download dataset NCEI Accession 0164568 v1.1 was published. 2017-08-04T23:03:19Z NCEI Accession 0164568 v1.1 publication https://www.ncei.noaa.gov/archive/accession/0164568/1.1 HTTPS NCEI Accession 0164568 v1.1 published 2017-08-04T23:03:19Z download asNeeded Metadata are developed, maintained and distributed by NCEI. Updates are performed as needed to maintain currentness. NOAA National Centers for Environmental Information custodian carbon dioxide (CO2) gas analyzer carbon dioxide (CO2) gas analyzer measures gaseous carbon dioxide Carbon dioxide gas analyzer has often been referred to as LI-COR, because a lot of researchers choose to use products manufactured by LI-COR incorporation for their carbon dioxide measurement. The main component of a carbon dioxide analyzer is a nondispersive infrared (NDIR) spectroscopic sensors to detect CO2 in a gaseous environment by its characteristic absorption. Carbon dioxide (CO2) gas analyzer works together with carbon dioxide (CO2) equilibrator (insttypes_id 184) to measure carbon dioxide in the water. To measure water carbon dioxide, water needs to be continuously supplied to a showerhead inside an equilibrator. As the water flows through the equilibrator chamber, dissolved carbon dioxide exchanges quickly with air in the headspace. This air is then sampled by the carbon dioxide analyzer to determine the mole fraction of CO2 in water. pH sensor pH sensor generic meter used to measure pH Any of a class of instruments used to quantify pH in a water or other type of sample. showerhead equilibrator showerhead equilibrator extracts dissolved CO2 from water A carbon dioxide equilibrator is usually in the shape of a vertical tube, with a showerhead on the top, some headspace, a lot of beads to increase the surface exchange area between water and air, a water seal device at the bottom to allow water to overflow, but prevents air exchange between inside and outside. Carbon dioxide (CO2) equilibrator works together with carbon dioxide (CO2) gas analyzer (insttypes_id 183) to measure carbon dioxide in the water. To measure water carbon dioxide, water needs to be continuously supplied to a showerhead inside an equilibrator. As the water flows through the equilibrator chamber, dissolved carbon dioxide exchanges quickly with air in the headspace. This air is then sampled by the carbon dioxide analyzer to determine the mole fraction of CO2 in water. titrator titrator titrator