Skip to main content
Dataset Overview | National Centers for Environmental Information (NCEI)

Dissolved inorganic carbon, total alkalinity, pH, and other variables collected from surface discrete observations using flow-through pump and other instruments during the M/V Equinox cruises in the North Atlantic ocean from 2015-03-07 to 2016-11-07 (NCEI Accession 0154382)

browse graphicPreview graphic
This dataset contains surface discrete measurements of dissolved inorganic carbon, total alkalinity, and pH from the east coast of Florida to Puerto Rico during the M/V Equinox cruises in the North Atlantic ocean from 2015-03-07 to 2016-11-07. Increasing amounts of atmospheric carbon dioxide from human industrial activities are causing changes in global ocean carbon chemistry. Through the SOOP program we measure air and ocean surface pCO2 and take discrete samples of other carbon parameters. This effort is in support of the coastal monitoring and research objectives of the NOAA Ocean Acidification Program (OAP) and the Climate Program Office.
  • Cite as: Barbero, Leticia; Wanninkhof, Rik; Pierrot, Denis (2016). Dissolved inorganic carbon, total alkalinity, pH, and other variables collected from surface discrete observations using flow-through pump and other instruments during the M/V Equinox cruises in the North Atlantic ocean from 2015-03-07 to 2016-11-07 (NCEI Accession 0154382). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.7289/v5p848zf. Accessed [date].
gov.noaa.nodc:0154382
Download Data
  • HTTPS (download)
    Navigate directly to the URL for data access and direct download.
  • FTP (download)
    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).
Distribution Formats
  • Originator data format
Ordering Instructions Contact NCEI for other distribution options and instructions.
Distributor NOAA National Centers for Environmental Information
+1-301-713-3277
NCEI.Info@noaa.gov
Dataset Point of Contact NOAA National Centers for Environmental Information
ncei.info@noaa.gov
Time Period 2015-03-07 to 2016-11-06
Spatial Bounding Box Coordinates
West: -78.9797
East: -10.3998
South: 19.2893
North: 38.4622
Spatial Coverage Map
General Documentation
Associated Resources
  • Wanninkhof, Rik; Pierrot, Denis; Huss, Betty E.; Sullivan, Kevin F.; Castle, Robert D. (2016). Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from Celebrity Equinox in the Adriatic Sea, Aegean Sea and others from 2015-02-23 to 2016-01-02 (NCEI Accession 0157224). NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.3334/cdiac/otg.vos_eqnx_2015.
  • Wanninkhof, Rik; Pierrot, Denis; Huss, Betty E.; Sullivan, Kevin F.; Castle, Robert D. (2016). Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer and other instruments from Celebrity Equinox in the Adriatic Sea, Aegean Sea and others from 2016-01-02 to 2017-01-02 (NCEI Accession 0157264). NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.3334/cdiac/otg.vos_eqnx_2016.
  • NOAA National Centers for Environmental Information (2022). Ocean Carbon and Acidification Data System (OCADS). NOAA National Centers for Environmental Information. https://www.ncei.noaa.gov/products/ocean-carbon-acidification-data-system
Publication Dates
  • publication: 2016-07-20
  • revision: 2021-07-29
Data Presentation Form Digital table - digital representation of facts or figures systematically displayed, especially in columns
Dataset Progress Status Complete - production of the data has been completed
Historical archive - data has been stored in an offline storage facility
Data Update Frequency As needed
Supplemental Information
EXPOCODE: MLCE20150306, MLCE20150428, MLCE20160415, MLCE20161030

CRUISE ID: EQNX_20150306, Equinox_0515, Equinox_1604, Equinox_1610

NOAA's Climate Program Office
PROJECT TITLE: Surface water pCO2 measurements from ships
PROJECT ID:

NOAA's Ocean Acidification Program
PROJECT TITLE: Quantifying sea-air CO2 fluxes using surface water pCO2 measurements from ships of opportunity, Ocean acidification Ship of Opportunity (SOOP)
PROJECT ID:

PRINCIPAL INVESTIGATORS:

Rik Wanninkhof {Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration (NOAA), 4301 Rickenbacker Causeway,
Miami, FL, 33149, USA}

Leticia Barbero {Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration (NOAA), 4301 Rickenbacker Causeway,
Miami, FL, 33149, USA}

Denis Pierrot {Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration (NOAA), 4301 Rickenbacker Causeway,
Miami, FL, 33149, USA}

In this accession, NCEI has archived multiple versions of these data. The latest (and best) version of these data has the largest version number.
Purpose To measure key carbon, physical and biogeochemical parameters in surfacel waters and monitor changes over time.
Use Limitations
  • accessLevel: Public
  • 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.
Dataset Citation
  • Cite as: Barbero, Leticia; Wanninkhof, Rik; Pierrot, Denis (2016). Dissolved inorganic carbon, total alkalinity, pH, and other variables collected from surface discrete observations using flow-through pump and other instruments during the M/V Equinox cruises in the North Atlantic ocean from 2015-03-07 to 2016-11-07 (NCEI Accession 0154382). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.7289/v5p848zf. Accessed [date].
Cited Authors
Principal Investigators
Contributors
Resource Providers
Publishers
Acknowledgments
  • Funding Information: NOAA Ocean Acidification Program (Coastal Observations on the East Coast: Ocean Acidification Monitoring Network, OAPFY13.03.AOML.001)
  • Funding Information: NOAA's Climate Program Office (Surface water pCO2 measurements from ships)
  • Funding Information: NOAA's Ocean Acidification Program (Quantifying sea-air CO2 fluxes using surface water pCO2 measurements from ships of opportunity, Ocean acidification Ship of Opportunity (SOOP))
Theme keywords NODC DATA TYPES THESAURUS NODC OBSERVATION TYPES THESAURUS WMO_CategoryCode
  • oceanography
Global Change Master Directory (GCMD) Science Keywords OCADS Study Type
  • Discrete measurement
  • Surface measurement
Provider Keywords
  • Equinox1503
Provider Variable Abbreviations
  • DIC
  • SAL
  • SST_C
  • TAlk
  • pH
Data Center keywords NODC COLLECTING INSTITUTION NAMES THESAURUS NODC SUBMITTING INSTITUTION NAMES THESAURUS Global Change Master Directory (GCMD) Data Center Keywords
Platform keywords NODC PLATFORM NAMES THESAURUS Global Change Master Directory (GCMD) Platform Keywords ICES/SeaDataNet Ship Codes
Instrument keywords NODC INSTRUMENT TYPES THESAURUS Global Change Master Directory (GCMD) Instrument Keywords
Place keywords NODC SEA AREA NAMES THESAURUS Global Change Master Directory (GCMD) Location Keywords Provider Geographic Names
  • North Atlantic Ocean
Project keywords NODC PROJECT NAMES THESAURUS Cruise ID
  • EQNX_20150306
  • EQNX_20150427
  • EQNX_20160415
  • EQNX_20161030
EXPOCODE
  • MLCE20150306
  • MLCE20150427
  • MLCE20160415
  • MLCE20161030
Ocean Acidification Search Keywords
  • Ocean Acidification Program (OAP)
  • Ocean Carbon and Acidification Data System (OCADS) Project
Keywords NCEI ACCESSION NUMBER
Use Constraints
  • Cite as: Barbero, Leticia; Wanninkhof, Rik; Pierrot, Denis (2016). Dissolved inorganic carbon, total alkalinity, pH, and other variables collected from surface discrete observations using flow-through pump and other instruments during the M/V Equinox cruises in the North Atlantic ocean from 2015-03-07 to 2016-11-07 (NCEI Accession 0154382). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.7289/v5p848zf. Accessed [date].
Access Constraints
  • 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.
Fees
  • 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.
Lineage information for: dataset
Processing Steps
  • 2016-07-20T10:01:23Z - NCEI Accession 0154382 v1.1 was published.
  • 2017-12-12T02:30:06Z - NCEI Accession 0154382 was revised and v2.2 was published.
    Rationale: Updates were received for this dataset. These updates were copied into the data/0-data/ directory of this accession. These updates may provide additional files or replace obsolete files. This version contains the most complete and up-to-date representation of this archival information package. All of the files received prior to this update are available in the preceding version of this accession.
  • 2020-09-22T17:33:54Z - NCEI Accession 0154382 was revised and v3.3 was published.
    Rationale: Updates were received for this dataset. These updates were copied into the data/0-data/ directory of this accession. These updates may provide additional files or replace obsolete files. This version contains the most complete and up-to-date representation of this archival information package. All of the files received prior to this update are available in the preceding version of this accession.
  • 2021-07-29T22:15:24Z - NCEI Accession 0154382 was revised and v4.4 was published.
    Rationale: Updates were received for this dataset. These updates were copied into the data/0-data/ directory of this accession. These updates may provide additional files or replace obsolete files. This version contains the most complete and up-to-date representation of this archival information package. All of the files received prior to this update are available in the preceding version of this accession.
Output Datasets
Lineage information for: dataset
Processing Steps
  • Parameter or Variable: Dissolved Inorganic Carbon; Abbreviation: DIC; Unit: micro-mol/kg; Observation type: Surface discrete measurement; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Flow through system; Analyzing instrument: Two systems consisting of a coulometer (UIC Inc.) coupled with a Dissolved Inorganic Carbon Extractor (DICE) inlet system. DICE was developed by Esa Peltola and Denis Pierrot of NOAA/AOML and Dana Greeley of NOAA/PMEL to modernize a carbon extractor called SOMMA (Johnson et al. 1985, 1987, 1993, and 1999; Johnson 1992); Detailed sampling and analyzing information: Samples for total dissolved inorganic carbon (DIC) measurements were drawn according to procedures outlined in the Guide to best practices for ocean CO2 measurements (Dickson et al., 2007) from Niskin bottles into cleaned 294-ml glass bottles. Bottles were rinsed and filled from the bottom, leaving 6 ml of headspace; care was taken not to entrain any bubbles. After 0.2 ml of saturated HgCl2 solution was added as a preservative, the sample bottles were sealed with glass stoppers lightly covered with Apiezon-L grease and were stored at room temperature to be sent back to the lab for analysis after the cruise. The analysis was done by coulometry with two analytical systems (AOML3 and AOML4) used simultaneously. In the coulometric analysis of DIC, all carbonate species are converted to CO2 (gas) by addition of excess hydrogen ion (acid) to the seawater sample, and the evolved CO2 gas is swept into the titration cell of the coulometer with pure air or compressed nitrogen, where it reacts quantitatively with a proprietary reagent based on ethanolamine to generate hydrogen ions. In this process, the solution changes from blue to colorless, triggering a current through the cell and causing coulometrical generation of OH minus ions at the anode. The OH ions react with the H+, and the solution turns blue again. A beam of light is shone through the solution, and a photometric detector at the opposite side of the cell senses the change in transmission. Once the percent transmission reaches its original value, the coulometric titration is stopped, and the amount of CO2 that enters the cell is determined by integrating the total charge during the titration. The volume of the pipette used to deliver the sample in each system was determined with aliquots of distilled water at known temperature. The weights with the appropriate densities were used to determine the volume of the pipette. Calculation of the amount of CO2 injected was according to the CO2 handbook (Dickson et al., 2007).The instrument has a salinity sensor, but all DIC values were recalculated to a molar weight (micro-mol/kg) using density obtained from the CTD salinity. The DIC values were corrected for dilution by 0.2 ml of saturated HgCl2 used for sample preservation (Measured DIC*1.00037). A correction was also applied for the offset from the CRM. This additive correction was applied for each cell using the CRM value obtained in the beginning of the cell. Please consult the accompanying Readme file for additional details.; Replicate information: 19 samples each 500-ml, 6 sets of duplicate samples.; Standardization description: The coulometers were calibrated by injecting aliquots of pure CO2 (99.99%) by means of an 8-port valve outfitted with two sample loops with known gas volumes bracketing the amount of CO2 extracted from the water samples for the two AOML systems.; Standardization frequency: The stability of each coulometer cell solution was confirmed three different ways: two sets of gas loops were measured at the beginning; also the Certified Reference Material (CRM), supplied by Dr. A. Dickson of UCSD, were measured at the beginning; and the duplicate samples at the beginning, middle, and end of each cell solution. The coulometer cell solution was replaced after 25 mg of carbon was titrated, typically after 9 to 12 hours of continuous use.; CRM manufacturer: Dr. A. Dickson of UCSD; CRM batch number: Batch 129, 144, 123; Preservation method: saturated HgCl2; Preservative volume: 0.2 ml; Preservative correction: The DIC values were corrected for dilution by 0.2 ml of saturated HgCl2 used for sample preservation. The total water volume of the sample bottles was 288 ml (calibrated by Esa Peltola, AOML). The correction factor used for dilution was 1.00037.; Quality flag convention: WOCE quality control flags are used: 2 = good value, 3 = questionable value, 4 = bad value, 5 = value not reported, 6 = mean of replicate measurements, 9 = sample not drawn.; Method reference: Dickson, A.G., Sabine, C.L. and Christian, J.R. (Eds.) 2007. Guide to best practices for ocean CO2 measurements. PICES Special Publication 3, 191 pp. Johnson, K.M., Kortzinger, A.; Mintrop, L.; Duinker, J.C.; and Wallace, D.W.R. (1999). Coulometric total carbon dioxide analysis for marine studies: Measurement and internal consistency of underway surface TCO2 concentrations. Marine Chemistry 67:123 to 44. Johnson, K.M., Wills, K.D.; Butler, D.B.; Johnson, W.K.; and Wong, C.S. (1993). Coulometric total carbon dioxide analysis for marine studies: Maximizing the performance of an automated gas extraction. Johnson, K.M. (1992). Operator Manual: Single-Operator Multiparameter Metabolic Analyzer (SOMMA) for Total Carbon Dioxide (CT) with Coulometric Detection. Brookhaven National Laboratory, Brookhaven, N.Y. Johnson, K.M.; Williams, P.J.; Brandstrom, L.; and McN. Sieburth, J. (1987). Coulometric total carbon analysis for marine studies: Automation and calibration. Marine Chemistry 21:117 to 33.; Researcher name: Rik Wanninkhof; Researcher institution: Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration (NOAA).
  • Parameter or Variable: Total alkalinity; Abbreviation: TAlk; Unit: micro-mol/kg; Observation type: Surface discrete measurement; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Flow through system; Analyzing instrument: Semi-automatic titration systems, System 1 consists of a Metrohm 765 Dosimat titrator, a pH meter (Orion 720A, ThermoScientific), a ROSS half cell pH glass electrode (Orion 9101BN, ThermoScientific) and a reference electrode (Orion 900200, ThermoScientific). System 2 consists of a Metrohm 665 Dosimat titrator, a pH meter (Orion 2 star pH Benchtop, ThermoScientific), a ROSS half cell pH glass electrode (Orion 9101BN, ThermoScientific) and a reference electrode (Orion 900200, ThermoScientific).; Type of titration: Full Titration; Cell type (open or closed): Open; Curve fitting method: Least-Square Analysis; Detailed sampling and analyzing information: All of the samples were run using leftover water from the same sample bottles used for DIC and pH. Please refer to DIC for detailed information on sampling and conservation of samples. For each measurement, approximately 200 ml of water sample were titrated with an HCl solution provided by Dr. Andrew Dickson of UCSD (0.25175 moles per kilogram-solution). Please consult the accompanying Readme file for additional details.; Replicate information: 19 samples each 500-ml, 6 sets of duplicate samples.; Standardization description: 2 CRM samples were run daily on each cell, before and after the seawater samples. The Total Alkalinity for the water samples was corrected using the daily averaged ratios between the certified and measured values of the 2 CRMs run on each cell. This TA titration system has a precision of 0.1 %. All the TA values were directly measured with reference to Certified Reference Material. The accuracy after correction is 0.1%. Please check attached pdf for more details.; Standardization frequency: All values were directly measured with reference to Certified Reference Material (Dickson, UCSD). 2 CRM samples were run daily on each cell.; CRM manufacturer: Dr. A. Dickson of UCSD; CRM batch number: CRM batch: 129, 144, 123; Preservation method: saturated HgCl2; Preservative volume: 0.2 ml; Uncertainty: The precision of this method is better than 0.1% and accuracy is 0.1%.; Quality flag convention: WOCE quality control flags are used: 2 = good value, 3 = questionable value, 4 = bad value, 5 = value not reported, 6 = mean of replicate measurements, 9 = sample not drawn.; Method reference: Millero, F. J., Zhang, J. Z., Lee, K., and Campbell, D. M. (1993). Titration alkalinity of seawater. Marine Chemistry, 44(2), 153-165.; Researcher name: Rik Wanninkhof; Researcher institution: Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration (NOAA).
  • Parameter or Variable: pH; Abbreviation: pH; pH scale: Total; Observation type: Surface discrete measurement; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Flow through system; Analyzing instrument: Agilent 8453 spectrometer setup with a custom-made temperature-controlled cell holder; Temperature of pH measurement: 20 (+/- 0.05) degrees Celsius; Detailed sampling and analyzing information: The same sample bottle was used for pH, DIC and Talk analyses, with pH being analyzed first. The samples were fixed with HgCl2 (refer to DIC for more information on sampling and storage). Samples were thermostated at 20 (+/- 0.05) degrees Celsius in a water bath. Approximately 80 ml of sample were extracted from each DIC sample bottle by syringe before DIC analysis to determine the pH. Temperature for each sample was measured before analysis using a Hart Scientific Fluke 1523 reference thermometer. Absorbance blanks were taken for each sample and 10 micro liter of purified m-cresol purple (10 mmol kg-1) were added for the analysis. The equations of Liu et al, 2011 formulated using the purified m-cresol purple indicator were used to determine pH of the samples. pH samples were analyzed at 20C. Please check accompanying readme file for additional details.; Replicate information: 19 samples each 500-ml, 6 sets of duplicate samples.; Standardization description: The pH is calibration-free.; At what temperature was pH reported: 20 degrees Celsius; Uncertainty: Please check attached pdf for more details; Quality flag convention: WOCE quality control flags are used: 2 = good value, 3 = questionable value, 4 = bad value, 5 = value not reported, 6 = mean of replicate measurements, 9 = sample not drawn.; Method reference: Liu, X.; Patsavas, M.C.; and Byrne, R. H. (2011). Purification and characterization of meta-cresol purple for spectrophotometric seawater pH measurements. Environmental Science and Technology, 45(11), 4862-4868. https://doi.org/10.1021/es200665d; Researcher name: Rik Wanninkhof; Researcher institution: Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration (NOAA).
  • Parameter or Variable: Water temperature; Abbreviation: SST_C; Unit: degrees celsius (ITS-90); Observation type: Flow-through; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: SBE 38; Uncertainty: plus or minus 0.001 degrees celsius; Quality flag convention: -999 indicates bad or missing data; Researcher name: Rik Wanninkhof; Researcher institution: Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration (NOAA).
  • Parameter or Variable: Salinity; Abbreviation: SAL; Unit: practical salinity scale of 1978; Observation type: Flow-through; In-situ / Manipulation / Response variable: In-situ observation; Sampling instrument: SBE 45; Uncertainty: plus or minus 0.005; Quality flag convention: -999 indicates bad or missing data; Researcher name: Rik Wanninkhof; Researcher institution: Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration (NOAA) .
Acquisition Information (collection)
Instrument
  • coulometer for DIC measurement
  • spectrophotometer
  • titrator
Platform
  • Celebrity Equinox
Last Modified: 2024-03-08T13:15:46Z
For questions about the information on this page, please email: ncei.info@noaa.gov