gov.noaa.nodc:0162262 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 2026-07-28T13:16:08Z ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) Measurements of total dissolved inorganic carbon (DIC), total alkalinity (TA) and pH (on total scale) and other variables collected from surface underway observations using Dissolved Inorganic Carbon Extractor (DICE), Metrohm 876 Dosimat Plus, Agilent 8453 spectrometer and other instruments from R/V Roger Revelle in the Indian Ocean during the transit time on GO-SHIP sections I08S and I09N (EXPOCODEs 33RR20160208 and 33RR20160321) from 2016-02-08 to 2016-03-24 (NCEI Accession 0162262) 2017-05-02 publication 2017-04-05 creation International DOI Foundation (IDF) 10.7289/v5th8jxg NOAA National Centers for Environmental Information gov.noaa.nodc:0162262 NCEI Archive Management System 0162262 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 Leticia Barbero Rosenstiel School of Marine, Atmospheric, and Earth Science Cooperative Institute for Marine and Atmospheric Studies (CIMAS) Leticia.Barbero@noaa.gov https://cimas.earth.miami.edu/ HTTPS Rosenstiel School of Marine, Atmospheric, and Earth Science Cooperative Institute for Marine and Atmospheric Studies (CIMAS) website Institution web page information resourceProvider NOAA Atlantic Oceanographic and Meteorological Laboratory (AOML) https://www.aoml.noaa.gov/ HTTPS NOAA Atlantic Oceanographic and Meteorological Laboratory (AOML) website Institution web page information resourceProvider Rik Wanninkhof NOAA Atlantic Oceanographic and Meteorological Laboratory (AOML) Rik.Wanninkhof@noaa.gov https://www.aoml.noaa.gov/ HTTPS NOAA Atlantic Oceanographic and Meteorological Laboratory (AOML) website Institution web page information principalInvestigator Andrew Dickson Scripps Institution of Oceanography (SIO) adickson@ucsd.edu https://scripps.ucsd.edu/ HTTPS Scripps Institution of Oceanography (SIO) website Institution web page information principalInvestigator James H. Swift Scripps Institution of Oceanography (SIO) scrippsnews@ucsd.edu https://scripps.ucsd.edu/ HTTPS Scripps Institution of Oceanography (SIO) website Institution web page information principalInvestigator Leticia Barbero Rosenstiel School of Marine, Atmospheric, and Earth Science Cooperative Institute for Marine and Atmospheric Studies (CIMAS) Leticia.Barbero@noaa.gov https://cimas.earth.miami.edu/ HTTPS Rosenstiel School of Marine, Atmospheric, and Earth Science Cooperative Institute for Marine and Atmospheric Studies (CIMAS) website Institution web page information principalInvestigator Swift, James H. Scripps Institution of Oceanography https://scripps.ucsd.edu/ HTTPS Scripps Institution of Oceanography (SIO) website Institution web page information author Barbero, Leticia Rosenstiel School of Marine, Atmospheric, and Earth Science Cooperative Institute for Marine and Atmospheric Studies https://cimas.earth.miami.edu/ HTTPS Rosenstiel School of Marine, Atmospheric, and Earth Science Cooperative Institute for Marine and Atmospheric Studies (CIMAS) website Institution web page information author Wanninkhof, Rik NOAA Atlantic Oceanographic and Meteorological Laboratory https://www.aoml.noaa.gov/ HTTPS NOAA Atlantic Oceanographic and Meteorological Laboratory (AOML) website Institution web page information author Dickson, Andrew G. Scripps Institution of Oceanography https://scripps.ucsd.edu/ HTTPS Scripps Institution of Oceanography (SIO) website Institution web page information author NOAA Atlantic Oceanographic and Meteorological Laboratory (AOML) https://www.aoml.noaa.gov/ HTTPS NOAA Atlantic Oceanographic and Meteorological Laboratory (AOML) website Institution web page information contributor Scripps Institution of Oceanography (SIO) https://scripps.ucsd.edu/ HTTPS Scripps Institution of Oceanography (SIO) website Institution web page information contributor tableDigital This dataset consists of the surface measurements of salinity, oxygen, total inorganic carbon, total alkalinity, pH on total scale, silicate, nitrate, nitrite, phosphate and NH4 collected under the Global Ocean Ship-based Hydrographic Investigations Program (GO-SHIP). GO-SHIP brings together scientists with interests in physical oceanography, the carbon cycle, marine biogeochemistry and ecosystems, and other users and collectors of ocean interior data, and coordinates a network of globally sustained hydrographic sections as part of the global ocean/climate observing system including physical oceanography, the carbon cycle, marine biogeochemistry and ecosystems. To measure carbon, physical and biogeochemical parameters that complement continuous surface measurements such as pCO2. Funding Information: NOAA's Ocean Observations and Monitoring Division (Surface Water Measurements from Ships of Opportunity (SOOP)) 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:0162262 Preview graphic PNG 0162262 NCEI ACCESSION NUMBER 2017-02-09 publication AMMONIA (NH3) DISSOLVED INORGANIC CARBON (DIC) DISSOLVED OXYGEN NUTRIENTS pH SALINITY total alkalinity WATER TEMPERATURE theme NODC DATA TYPES THESAURUS titrator instrument NODC INSTRUMENT TYPES THESAURUS chemical physical surface underway theme NODC OBSERVATION TYPES THESAURUS R/V Roger Revelle platform NODC PLATFORM NAMES THESAURUS NOAA Atlantic Oceanographic and Meteorological Laboratory Scripps Institution of Oceanography dataCentre NODC COLLECTING INSTITUTION NAMES THESAURUS NOAA Atlantic Oceanographic and Meteorological Laboratory dataCentre NODC SUBMITTING INSTITUTION NAMES THESAURUS The Global Ocean Ship-based Hydrographic Investigations Program (GO-SHIP) project NODC PROJECT NAMES THESAURUS Indian Ocean place NODC SEA AREA NAMES THESAURUS oceanography theme WMO_CategoryCode 2012-09-15 publication DOC/NOAA/OAR/AOML > Atlantic Oceanographic and Meteorological Laboratory, OAR, NOAA, U.S. Department of Commerce 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 GO-SHIP_I08S GO-SHIP_I09N project Cruise ID 33RR20160208 33RR20160321 project EXPOCODE Ocean Carbon and Acidification Data System (OCADS) Project project Ocean Acidification Search Keywords I08S/I09N project Reference Section ID The Global Ocean Ship-based Hydrographic Investigations Program (GO-SHIP) project Research Projects EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > ALKALINITY EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > AMMONIA EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > INORGANIC CARBON EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > NUTRIENTS EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > OXYGEN EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > PH EARTH SCIENCE > OCEANS > OCEAN TEMPERATURE > WATER TEMPERATURE EARTH SCIENCE > OCEANS > SALINITY/DENSITY > SALINITY 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 Surface underway theme OCADS Study Type GO-SHIP Section I08S/I09N theme Provider Keywords ALKALI CTDTMP DIC NH4 NITRAT NITRIT OXYGEN PHSPHT SALNTY SILCAT pH theme Provider Variable Abbreviations Potentiometric titrator for dissolved inorganic carbon (DIC) and total alkalinity (TA) measurement instrument Ocean Acidification Instrument Keywords Ships platform Global Change Master Directory (GCMD) Platform 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 ROGER REVELLE (call sign: KAOU, ICES code: 33RR, 1996-) platform ICES/SeaDataNet Ship Codes OCEAN > INDIAN 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 Indian Ocean place Provider Geographic Names accessLevel: public otherRestrictions Cite as: Swift, James H.; Barbero, Leticia; Wanninkhof, Rik; Dickson, Andrew G. (2017). Measurements of total dissolved inorganic carbon (DIC), total alkalinity (TA) and pH (on total scale) and other variables collected from surface underway observations using Dissolved Inorganic Carbon Extractor (DICE), Metrohm 876 Dosimat Plus, Agilent 8453 spectrometer and other instruments from R/V Roger Revelle in the Indian Ocean during the transit time on GO-SHIP sections I08S and I09N (EXPOCODEs 33RR20160208 and 33RR20160321) from 2016-02-08 to 2016-03-24 (NCEI Accession 0162262). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.7289/v5th8jxg. 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. 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 2022-04 publication https://www.ncei.noaa.gov/products/ocean-carbon-acidification-data-system HTTPS https://www.ncei.noaa.gov/products/ocean-carbon-acidification-data-system OCADS website information NOAA National Centers for Environmental Information author NOAA National Centers for Environmental Information (NCEI) publisher documentDigital [accessed 2024-02-08] crossReference program eng; USA utf8 environment oceans 76.3 115.8 -65.3 -28.1 2016-02-08 2016-03-24 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 0.356 https://www.ncei.noaa.gov/data/oceans/ncei/ocads/metadata/0162262.html HTTPS Web browser Project Metadata Navigate directly to the URL for a descriptive web page with download links. information https://doi.org/10.7289/v5th8jxg 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/162262 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/162262 HTTPS Web browser HTTPS Navigate directly to the URL for data access and direct download. download ftp://ftp-oceans.ncei.noaa.gov/nodc/archive/arc0106/0162262/ 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 0162262 v1.1 was published. 2017-05-02T12:11:07Z NCEI Accession 0162262 v1.1 publication https://www.ncei.noaa.gov/archive/accession/0162262/1.1 HTTPS NCEI Accession 0162262 v1.1 published 2017-05-02T12:11:07Z download dataset Parameter or Variable: Dissolved Inorganic Carbon; Abbreviation: DIC; Unit: UMOL/KG; Observation type: surface underway; 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 the underway line 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: 14 sets of duplicate samples, with an average difference of 1.24 μmol/kg and an average STDEV of 0.88.; 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 SIO, UCSD; CRM batch number: Batch 152; 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., Körtzinger, 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: ALKALI; Unit: UMOL/KG; Observation type: surface underway; Measured or calculated: measured; Sampling instrument: Flow through system; Analyzing instrument: Metrohm 876 Dosimat Plus is used for all standardized hydrochloric acid additions. An Agilent 34970A Data Acquisition/Switch Unit with a 34901A multiplexer is used to read the voltage measurements from the electrode and monitor the temperatures from the sample, acid, and room. The calculations for this procedure are performed automatically using LabVIEW 2012.; Type of titration: Full Titration; Cell type (open or closed): Open; Curve fitting method: Least-Square Analysis; Detailed sampling and analyzing information: Samples are dispensed using a Sample Delivery System (SDS) consisting of a volumetric pipette, various relay valves, and two air pumps controlled by LabVIEW 2012. Before filling the jacketed cell with a new sample for analysis, the volumetric pipette is cleared of any residual from the previous sample with the aforementioned air pumps. The pipette is then rinsed with new sample and filled, allowing for overflow and time for the sample temperature to equilibrate. The sample bottle temperature is measured using a DirecTemp thermistor probe inserted into the sample bottle and the volumetric pipette temperature is measured using a DirecTemp surface probe placed directly on the pipette. These temperature measurements are used to convert the sample volume to mass for analysis. Samples are analyzed using an open cell titration procedure using two 250 mL jacketed cells. One sample is undergoing titration while the second is being prepared and equilibrating to 20C for analysis. After an initial aliquot of approximately 2.3-2.4 mL of standardized hydrochloric acid (~0.1M HCl in ~0.6M NaCl solution), the sample is stirred for 5 minutes while air is bubbled into it at a rate of 200 scc/m to remove any liberated carbon dioxide gas. A Metrohm 876 Dosimat Plus is used for all standardized hydrochloric acid additions. After equilibration, ~19 aliquots of 0.04 ml are added. Between the pH range of 3.5 to 3.0, the progress of the titration is monitored using a pH glass electrode/reference electrode cell, and the total alkalinity is computed from the titrant volume and e.m.f. measurements using a non-linear least-squares approach ([Dickson2007]). An Agilent 34970A Data Acquisition/Switch Unit with a 34901A multiplexer is used to read the voltage measurements from the electrode and monitor the temperatures from the sample, acid, and room. The calculations for this procedure are performed automatically using LabVIEW 2012.; Replicate information: Two Niskin bottles at each station were sampled twice for duplicate measurements except for stations where 15 or less Niskin bottles were sampled; Standardization description: At least one reference material was analyzed at every station resulting in 108 (I08S) and 110 (I09N) reference material analyses.; Standardization frequency: All values were directly measured with reference to Certified Reference Material (Dickson, UCSD).; CRM manufacturer: Dr. A. Dickson of SIO, UCSD; CRM batch number: CRM batch: 152 and 153; 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: 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.; Researcher name: Andrew Dickson; Researcher institution: SIO, UCSD Parameter or Variable: pH; Abbreviation: pH; pH scale: Total; Observation type: surface underway; 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: 25 (+/- 0.05) degrees Celsius; Detailed sampling and analyzing information: Samples were collected in 250 mL Pyrex glass bottles and sealed using grey butyl rubber stoppers held in place by aluminum-crimped caps. Each bottle was rinsed two times and allowed to overflow by one additional bottle volume. Prior to sealing, each sample was given a 1% headspace and poisoned with 0.02% of the sample volume of saturated mercuric chloride (HgCl2). Samples were collected only from Niskin bottles that were also being sampled for both total alkalinity and dissolved inorganic carbon in order to completely characterize the carbon system. Additionally, two duplicate samples were collected from almost all stations for quality control purposes. pH was measured spectrophotometrically on the total hydrogen scale using an Agilent 8453 spectrophotometer and in accordance with the methods outlined by Carter et al., 2013 [Carter2013]. A Kloehn V6 syringe pump was used to autonomously fill, mix, and dispense sample through the custom 10cm flow-through jacketed cell. A Thermo NESLAB RTE-7 recirculating water bath was used to maintain the cell temperature at 25.0 degC during analyses, and a YSI 4600 precision thermometer and probe were used to monitor and record the temperature of each sample immediately after the spectrophotometric measurements were taken. The indicator meta-cresol purple (mCP) was used to measure the absorbance of light measured at two different wavelengths (434 nm, 578 nm) corresponding to the maximum absorbance peaks for the acidic and basic forms of the indicator dye. A baseline absorbance was also measured and subtracted from these wavelengths. The baseline absorbance was determined by averaging the absorbances from 725-735nm. The ratio of the absorbances was then used to calculate pH on the total scale using the equations outlined in Liu et al., 2011 [Liu2011]. The salinity data used was obtained from the conductivity sensor on the CTD.; Replicate information: Two duplicate and two replicate measurements were performed on every station when at least fifteen Niskins were sampled. If less than fifteen Niskins were sampled, only one duplicate and one replicate measurement were performed.; Standardization description: The precision of the data was assessed from measurements of duplicate analyses, replicate analyses (two successive measurements on one bottle), and certified reference material (CRM) Batch 152 and Batch 153 (provided by Dr. Andrew Dickson, UCSD).; At what temperature was pH reported: 25 degrees Celsius; 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: Andrew Dickson; Researcher institution: SIO, UCSD Parameter or Variable: Sea Surface Temperature; Abbreviation: CTDTMP; Unit: degrees celcius; Observation type: Surface Underway; Analyzing instrument: CTD; Detailed sampling and analyzing information: In Bow Thruster room, about 1m after the intake which is directly through the ship's hull, before the SW pump; Uncertainty: plus or minus 0.001 degrees celsius; Researcher name: Jim Swift; Researcher institution: SIO, UCSD Parameter or Variable: Sea Surface Salinity; Abbreviation: SALNTY; Observation type: Surface Underway; Analyzing instrument: CTD; Uncertainty: plus or minus 0.01 PSS-78; Researcher name: James Swift; Researcher institution: SIO/UCSD Parameter or Variable: Dissolved Oxygen; Abbreviation: OXYGEN; Unit: UMOL/KG; Observation type: surfase underway; Sampling instrument: Flow through system; Analyzing instrument: Dissolved oxygen analyses were performed with an SIO/ODF-designed automated oxygen titrator using photometric end-point detection based on the absorption of 365nm wavelength ultra-violet light. The titration of the samples and the data logging were controlled by PC LabView software.; Detailed sampling and analyzing information: Samples were collected for dissolved oxygen analyses soon after the rosette was brought on board. Using a silicone drawing tube, nominal 125ml volume-calibrated iodine flasks were rinsed 3 times with minimal agitation, then filled and allowed to overflow for at least 3 flask volumes. The sample drawing temperatures were measured with an electronic resistance temperature detector (RTD) embedded in the drawing tube. These temperatures were used to calculate μmol/kg concentrations, and as a diagnostic check of bottle integrity. Reagents (MnCl2 then NaI/NaOH) were added to fix the oxygen before stoppering. The flasks were shaken twice (10-12 inversions) to assure thorough dispersion of the precipitate, once immediately after drawing, and then again after about 30-40 minutes. The samples were analyzed within 2-14 hours of collection, and the data incorporated into the cruise database. Thiosulfate was dispensed by a Dosimat 765 buret driver fitted with a 1.0 ml burette. ODF used a whole-bottle modified-Winkler titration following the technique of Carpenter [Carpenter1965] with modifications by [Culberson1991] but with higher concentrations of potassium iodate standard approximately 0.012N, and thiosulfate solution approximately 55 gm/l. Pre-made liquid potassium iodate standards were run every day (approximately every 4-5 stations), unless changes were made to the system or reagents. Reagent/distilled water blanks were determined every day or more often if a change in reagents required it to account for presence of oxidizing or reducing agents.; Uncertainty: Liquid potassium iodate standards were prepared in 6 liter batches and bottled in sterile glass bottles at ODF's chemistry laboratory prior to the expedition. The normality of the liquid standard was determined by calculation from weight. The standard was supplied by Alfa Aesar and has a reported purity of 99.4-100.4%. All other reagents were "reagent grade" and were tested for levels of oxidizing and reducing impurities prior to use.; 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: Culberson, C. H., Knapp, G., Stalcup, M., Williams, R. T., and Zemlyak, F. A comparison of methods for the deter mination of dissolved oxygen in seawater. Report WHPO 91-2, WOCE Hydrographic Programme Office (Aug 1991).; Researcher name: James Swift; Researcher institution: SIO/UCSD Parameter or Variable: Silicate; Abbreviation: SILCAT; Unit: UMOL/KG; Observation type: surfase underway; Sampling instrument: Flow through system; Analyzing instrument: Nutrient analyses (phosphate, silicate, nitrate+nitrite, and nitrite) were performed on a Seal Analytical continuous-flow AutoAnalyzer 3 (AA3).; Detailed sampling and analyzing information: Nutrient samples were drawn into 40 ml polypropylene screw-capped centrifuge tubes. The tubes and caps were cleaned with 10% HCl and rinsed 2-3 times with sample before filling. Samples were analyzed within 1-3 hours after sample collection, allowing sufficient time for all samples to reach room temperature. The centrifuge tubes fit directly onto the sampler. The methods used are described by Gordon et al. 1992; Hager et al. 1972, and Atlas et al.1971. Details of modification of analytical methods used in this cruise are also compatible with the methods described in the nutrient section of the GO-SHIP repeat hydrography manual (Hydes et al., 2010). Silicate was analyzed using the basic method of Armstrong et al. (1967). Acidified ammonium molybdate was added to a seawater sample to produce silicomolybdic acid which was then reduced to silicomolybdous acid (a blue compound) following the addition of stannous chloride. The sample was passed through a 10mm flowcell and measured at 660nm.; Uncertainty: Primary standards for silicate (Na2SiF6), nitrate (KNO3), nitrite (NaNO2), and phosphate (KH2PO4) were obtained from Johnson Matthey Chemical Co. and/or Fisher Scientific. The supplier reports purities of >98%, 99.999%, 97%, and 99.999 respectively. All glass volumetric flasks and pipettes were gravimetrically calibrated prior to the cruise. The primary standards were dried and weighed out to 0.1mg prior to the cruise. The exact weight was noted for future reference. When primary standards were made, the flask volume at 20C, the weight of the powder, and the temperature of the solution were used to buoyancy-correct the weight, calculate the exact concentration of the solution, and determine how much of the primary was needed for the desired concentrations of secondary standard. Primary and secondary standards were made up every 7-10days. The new standards were compared to the old before use. All the reagent solutions, primary and secondary standards were made with fresh distilled deionized water (DIW). Standardizations were performed at the beginning of each group of analyses with working standards prepared prior to each run from a secondary. Working standards were made up in low nutrient seawater (LNSW). LNSW used for this cruise was deep water collected at a test station at the beginning of the cruise track. The actual concentration of nutrients in this water was empirically determined during the standardization calculations.; 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: Hydes, D.J., Aoyama, M., Aminot, A., Bakker, K., Becker, S., Coverly, S., Daniel, A., Dickson, A.G., Grosso, O., Kerouel, R., Ooijen, J. van, Sato, K., Tanhua, T., Woodward, E.M.S., Zhang, J.Z., 2010. Determination of Dissolved Nutrients (N, P, Si) in Seawater with High Precision and Inter-Comparability Using Gas-Segmented Continuous Flow Analysers, In: GO-SHIP Repeat Hydrography Manual: A Collection of Expert Reports and Guidelines. IOCCP Report No. 14, ICPO Publication Series No 134. Armstrong, F.A.J., Stearns, C.A., and Strickland, J.D.H. The measurement of upwelling and subsequent biological processes by means of the Technicon Autoanalyzer and associated equipment. Deep-Sea Research, 14, pp.381-389 (1967).; Researcher name: James Swift; Researcher institution: SIO/UCSD Parameter or Variable: Nitrate; Abbreviation: NITRAT; Unit: UMOL/KG; Observation type: surfase underway; Sampling instrument: Flow through system; Analyzing instrument: Nutrient analyses (phosphate, silicate, nitrate+nitrite, and nitrite) were performed on a Seal Analytical continuous-flow AutoAnalyzer 3 (AA3).; Detailed sampling and analyzing information: Nutrient samples were drawn into 40 ml polypropylene screw-capped centrifuge tubes. The tubes and caps were cleaned with 10% HCl and rinsed 2-3 times with sample before filling. Samples were analyzed within 1-3 hours after sample collection, allowing sufficient time for all samples to reach room temperature. The centrifuge tubes fit directly onto the sampler. The methods used are described by Gordon et al. 1992; Hager et al. 1972, and Atlas et al.1971. Details of modification of analytical methods used in this cruise are also compatible with the methods described in the nutrient section of the GO-SHIP repeat hydrography manual (Hydes et al., 2010). A modification of the Armstrong et al. (1967) [Armstrong1967] procedure was used for the analysis of nitrate and nitrite. For nitrate analysis, a seawater sample was passed through a cadmium column where the nitrate was reduced to nitrite. This nitrite was then diazotized with sulfanilamide and coupled with N-(1-naphthyl)-ethylenediamine to form a red dye. The sample was then passed through a 10mm flowcell and absorbance measured at 540nm. The procedure was the same for the nitrite analysis but without the cadmium column.; Uncertainty: Primary standards for silicate (Na2SiF6), nitrate (KNO3), nitrite (NaNO2), and phosphate (KH2PO4) were obtained from Johnson Matthey Chemical Co. and/or Fisher Scientific. The supplier reports purities of >98%, 99.999%, 97%, and 99.999 respectively. All glass volumetric flasks and pipettes were gravimetrically calibrated prior to the cruise. The primary standards were dried and weighed out to 0.1mg prior to the cruise. The exact weight was noted for future reference. When primary standards were made, the flask volume at 20C, the weight of the powder, and the temperature of the solution were used to buoyancy-correct the weight, calculate the exact concentration of the solution, and determine how much of the primary was needed for the desired concentrations of secondary standard. Primary and secondary standards were made up every 7-10days. The new standards were compared to the old before use. All the reagent solutions, primary and secondary standards were made with fresh distilled deionized water (DIW). Standardizations were performed at the beginning of each group of analyses with working standards prepared prior to each run from a secondary. Working standards were made up in low nutrient seawater (LNSW). LNSW used for this cruise was deep water collected at a test station at the beginning of the cruise track. The actual concentration of nutrients in this water was empirically determined during the standardization calculations.; 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: Hydes, D.J., Aoyama, M., Aminot, A., Bakker, K., Becker, S., Coverly, S., Daniel, A., Dickson, A.G., Grosso, O., Kerouel, R., Ooijen, J. van, Sato, K., Tanhua, T., Woodward, E.M.S., Zhang, J.Z., 2010. Determination of Dissolved Nutrients (N, P, Si) in Seawater with High Precision and Inter-Comparability Using Gas-Segmented Continuous Flow Analysers, In: GO-SHIP Repeat Hydrography Manual: A Collection of Expert Reports and Guidelines. IOCCP Report No. 14, ICPO Publication Series No 134. Armstrong, F.A.J., Stearns, C.A., and Strickland, J.D.H. The measurement of upwelling and subsequent biological processes by means of the Technicon Autoanalyzer and associated equipment. Deep-Sea Research, 14, pp.381-389 (1967).; Researcher name: James Swift; Researcher institution: SIO/UCSD Parameter or Variable: Nitrite; Abbreviation: NITRIT; Unit: UMOL/KG; Observation type: surfase underway; Sampling instrument: Flow through system; Analyzing instrument: Nutrient analyses (phosphate, silicate, nitrate+nitrite, and nitrite) were performed on a Seal Analytical continuous-flow AutoAnalyzer 3 (AA3).; Detailed sampling and analyzing information: Nutrient samples were drawn into 40 ml polypropylene screw-capped centrifuge tubes. The tubes and caps were cleaned with 10% HCl and rinsed 2-3 times with sample before filling. Samples were analyzed within 1-3 hours after sample collection, allowing sufficient time for all samples to reach room temperature. The centrifuge tubes fit directly onto the sampler. The methods used are described by Gordon et al. 1992; Hager et al. 1972, and Atlas et al.1971. Details of modification of analytical methods used in this cruise are also compatible with the methods described in the nutrient section of the GO-SHIP repeat hydrography manual (Hydes et al., 2010). A modification of the Armstrong et al. (1967) [Armstrong1967] procedure was used for the analysis of nitrate and nitrite. For nitrate analysis, a seawater sample was passed through a cadmium column where the nitrate was reduced to nitrite. This nitrite was then diazotized with sulfanilamide and coupled with N-(1-naphthyl)-ethylenediamine to form a red dye. The sample was then passed through a 10mm flowcell and absorbance measured at 540nm. The procedure was the same for the nitrite analysis but without the cadmium column.; Uncertainty: Primary standards for silicate (Na2SiF6), nitrate (KNO3), nitrite (NaNO2), and phosphate (KH2PO4) were obtained from Johnson Matthey Chemical Co. and/or Fisher Scientific. The supplier reports purities of >98%, 99.999%, 97%, and 99.999 respectively. All glass volumetric flasks and pipettes were gravimetrically calibrated prior to the cruise. The primary standards were dried and weighed out to 0.1mg prior to the cruise. The exact weight was noted for future reference. When primary standards were made, the flask volume at 20C, the weight of the powder, and the temperature of the solution were used to buoyancy-correct the weight, calculate the exact concentration of the solution, and determine how much of the primary was needed for the desired concentrations of secondary standard. Primary and secondary standards were made up every 7-10days. The new standards were compared to the old before use. All the reagent solutions, primary and secondary standards were made with fresh distilled deionized water (DIW). Standardizations were performed at the beginning of each group of analyses with working standards prepared prior to each run from a secondary. Working standards were made up in low nutrient seawater (LNSW). LNSW used for this cruise was deep water collected at a test station at the beginning of the cruise track. The actual concentration of nutrients in this water was empirically determined during the standardization calculations.; 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: Hydes, D.J., Aoyama, M., Aminot, A., Bakker, K., Becker, S., Coverly, S., Daniel, A., Dickson, A.G., Grosso, O., Kerouel, R., Ooijen, J. van, Sato, K., Tanhua, T., Woodward, E.M.S., Zhang, J.Z., 2010. Determination of Dissolved Nutrients (N, P, Si) in Seawater with High Precision and Inter-Comparability Using Gas-Segmented Continuous Flow Analysers, In: GO-SHIP Repeat Hydrography Manual: A Collection of Expert Reports and Guidelines. IOCCP Report No. 14, ICPO Publication Series No 134. Armstrong, F.A.J., Stearns, C.A., and Strickland, J.D.H. The measurement of upwelling and subsequent biological processes by means of the Technicon Autoanalyzer and associated equipment. Deep-Sea Research, 14, pp.381-389 (1967).; Researcher name: James Swift; Researcher institution: SIO/UCSD Parameter or Variable: Phosphate; Abbreviation: PHSPHT; Unit: UMOL/KG; Observation type: surfase underway; Sampling instrument: Flow through system; Analyzing instrument: Nutrient analyses (phosphate, silicate, nitrate+nitrite, and nitrite) were performed on a Seal Analytical continuous-flow AutoAnalyzer 3 (AA3).; Detailed sampling and analyzing information: Nutrient samples were drawn into 40 ml polypropylene screw-capped centrifuge tubes. The tubes and caps were cleaned with 10% HCl and rinsed 2-3 times with sample before filling. Samples were analyzed within 1-3 hours after sample collection, allowing sufficient time for all samples to reach room temperature. The centrifuge tubes fit directly onto the sampler. The methods used are described by Gordon et al. 1992; Hager et al. 1972, and Atlas et al.1971. Details of modification of analytical methods used in this cruise are also compatible with the methods described in the nutrient section of the GO-SHIP repeat hydrography manual (Hydes et al., 2010). A modification of the Armstrong et al. (1967) [Armstrong1967] procedure was used for the analysis of nitrate and nitrite. For nitrate analysis, a seawater sample was passed through a cadmium column where the nitrate was reduced to nitrite. This nitrite was then diazotized with sulfanilamide and coupled with N-(1-naphthyl)-ethylenediamine to form a red dye. The sample was then passed through a 10mm flowcell and absorbance measured at 540nm. The procedure was the same for the nitrite analysis but without the cadmium column.; Uncertainty: Primary standards for silicate (Na2SiF6), nitrate (KNO3), nitrite (NaNO2), and phosphate (KH2PO4) were obtained from Johnson Matthey Chemical Co. and/or Fisher Scientific. The supplier reports purities of >98%, 99.999%, 97%, and 99.999 respectively. All glass volumetric flasks and pipettes were gravimetrically calibrated prior to the cruise. The primary standards were dried and weighed out to 0.1mg prior to the cruise. The exact weight was noted for future reference. When primary standards were made, the flask volume at 20C, the weight of the powder, and the temperature of the solution were used to buoyancy-correct the weight, calculate the exact concentration of the solution, and determine how much of the primary was needed for the desired concentrations of secondary standard. Primary and secondary standards were made up every 7-10days. The new standards were compared to the old before use. All the reagent solutions, primary and secondary standards were made with fresh distilled deionized water (DIW). Standardizations were performed at the beginning of each group of analyses with working standards prepared prior to each run from a secondary. Working standards were made up in low nutrient seawater (LNSW). LNSW used for this cruise was deep water collected at a test station at the beginning of the cruise track. The actual concentration of nutrients in this water was empirically determined during the standardization calculations.; 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: Hydes, D.J., Aoyama, M., Aminot, A., Bakker, K., Becker, S., Coverly, S., Daniel, A., Dickson, A.G., Grosso, O., Kerouel, R., Ooijen, J. van, Sato, K., Tanhua, T., Woodward, E.M.S., Zhang, J.Z., 2010. Determination of Dissolved Nutrients (N, P, Si) in Seawater with High Precision and Inter-Comparability Using Gas-Segmented Continuous Flow Analysers, In: GO-SHIP Repeat Hydrography Manual: A Collection of Expert Reports and Guidelines. IOCCP Report No. 14, ICPO Publication Series No 134. Armstrong, F.A.J., Stearns, C.A., and Strickland, J.D.H. The measurement of upwelling and subsequent biological processes by means of the Technicon Autoanalyzer and associated equipment. Deep-Sea Research, 14, pp.381-389 (1967).; Researcher name: James Swift; Researcher institution: SIO/UCSD Parameter or Variable: Ammonia; Abbreviation: NH4; Unit: UMOL/KG; Observation type: surfase underway; Sampling instrument: Flow through system; Analyzing instrument: Nutrient analyses (phosphate, silicate, nitrate+nitrite, and nitrite) were performed on a Seal Analytical continuous-flow AutoAnalyzer 3 (AA3).; Detailed sampling and analyzing information: Nutrient samples were drawn into 40 ml polypropylene screw-capped centrifuge tubes. The tubes and caps were cleaned with 10% HCl and rinsed 2-3 times with sample before filling. Samples were analyzed within 1-3 hours after sample collection, allowing sufficient time for all samples to reach room temperature. The centrifuge tubes fit directly onto the sampler. The methods used are described by Gordon et al. 1992; Hager et al. 1972, and Atlas et al.1971. Details of modification of analytical methods used in this cruise are also compatible with the methods described in the nutrient section of the GO-SHIP repeat hydrography manual (Hydes et al., 2010). A modification of the Armstrong et al. (1967) [Armstrong1967] procedure was used for the analysis of nitrate and nitrite. For nitrate analysis, a seawater sample was passed through a cadmium column where the nitrate was reduced to nitrite. This nitrite was then diazotized with sulfanilamide and coupled with N-(1-naphthyl)-ethylenediamine to form a red dye. The sample was then passed through a 10mm flowcell and absorbance measured at 540nm. The procedure was the same for the nitrite analysis but without the cadmium column.; Uncertainty: Primary standards for silicate (Na2SiF6), nitrate (KNO3), nitrite (NaNO2), and phosphate (KH2PO4) were obtained from Johnson Matthey Chemical Co. and/or Fisher Scientific. The supplier reports purities of >98%, 99.999%, 97%, and 99.999 respectively. All glass volumetric flasks and pipettes were gravimetrically calibrated prior to the cruise. The primary standards were dried and weighed out to 0.1mg prior to the cruise. The exact weight was noted for future reference. When primary standards were made, the flask volume at 20C, the weight of the powder, and the temperature of the solution were used to buoyancy-correct the weight, calculate the exact concentration of the solution, and determine how much of the primary was needed for the desired concentrations of secondary standard. Primary and secondary standards were made up every 7-10days. The new standards were compared to the old before use. All the reagent solutions, primary and secondary standards were made with fresh distilled deionized water (DIW). Standardizations were performed at the beginning of each group of analyses with working standards prepared prior to each run from a secondary. Working standards were made up in low nutrient seawater (LNSW). LNSW used for this cruise was deep water collected at a test station at the beginning of the cruise track. The actual concentration of nutrients in this water was empirically determined during the standardization calculations.; 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: Hydes, D.J., Aoyama, M., Aminot, A., Bakker, K., Becker, S., Coverly, S., Daniel, A., Dickson, A.G., Grosso, O., Kerouel, R., Ooijen, J. van, Sato, K., Tanhua, T., Woodward, E.M.S., Zhang, J.Z., 2010. Determination of Dissolved Nutrients (N, P, Si) in Seawater with High Precision and Inter-Comparability Using Gas-Segmented Continuous Flow Analysers, In: GO-SHIP Repeat Hydrography Manual: A Collection of Expert Reports and Guidelines. IOCCP Report No. 14, ICPO Publication Series No 134. Armstrong, F.A.J., Stearns, C.A., and Strickland, J.D.H. The measurement of upwelling and subsequent biological processes by means of the Technicon Autoanalyzer and associated equipment. Deep-Sea Research, 14, pp.381-389 (1967).; Researcher name: James Swift; Researcher institution: SIO/UCSD asNeeded Metadata are developed, maintained and distributed by NCEI. Updates are performed as needed to maintain currentness. NOAA National Centers for Environmental Information custodian titrator titrator titrator R/V Roger Revelle Flag: United States Type: Research Vessel IMO: 9075228 Company: Scripps Institution of Oceanography DOB: 1996-06 https://scripps.ucsd.edu/ships/revelle