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Dissolved inorganic carbon, total alkalinity, pH, Oxygen, and other variables collected from surface discrete observations using flow-through pump and other instruments in the East Coast of the U.S. and Canada during the 2nd East Coast Ocean Acidification (ECOA2, or ECOA-2) cruise from 2018-06-26 to 2018-07-28 (NCEI Accession 0196423)

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This dataset contains the surface discrete measurements that were collected via the onboard flow-through system while the boat was moving and CTD casts were not taken during the East Coast Ocean Acidification (ECOA2) Cruise on board NOAA Ship Henry B. Bigelow. The cruise started from Newport, took place in the Gulf of Maine and then along the East US coast to Miami. The effort was in support of the coastal monitoring and research objectives of the NOAA Ocean Acidification Program (OAP). The cruise was designed to obtain a snapshot of key carbon, physical, and biogeochemical parameters as they relate to ocean acidification (OA) in the coastal realm. The cruise included a series of 14 transects approximately orthogonal to the Gulf of Maine and Atlantic coasts and a comprehensive set of underway measurements along the entire transect.
  • Cite as: Salisbury, Joseph E.; Shellito, Shawn M. (2019). Dissolved inorganic carbon, total alkalinity, pH, Oxygen, and other variables collected from surface discrete observations using flow-through pump and other instruments in the East Coast of the U.S. and Canada during the 2nd East Coast Ocean Acidification (ECOA2, or ECOA-2) cruise from 2018-06-26 to 2018-07-28 (NCEI Accession 0196423). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/bh9e-we02. Accessed [date].
gov.noaa.nodc:0196423
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  • Originator data format
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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 2018-06-26 to 2018-07-28
Spatial Bounding Box Coordinates
West: -80.5878
East: -61.9613
South: 27.224
North: 44.5726
Spatial Coverage Map
General Documentation
Associated Resources
  • Salisbury, J. and Shellito S. 2017. ECOA Report.
  • Salisbury, Joseph E.; Shellito, Shawn M. (2019). Dissolved inorganic carbon, total alkalinity, pH, nutrients and other variables collected from discrete profile observations using CTD, Niskin bottle, and other instruments in the East Coast of the U.S. and Canada during the 2nd East Coast Ocean Acidification (ECOA2, or ECOA-2) cruise from 2018-06-25 to 2018-07-29 (NCEI Accession 0196419). NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/f4vg-g356.
  • Salisbury, Joseph E.; Shellito, Shawn M. (2019). Dissolved oxygen, fluorescence, PAR, temperature, salinity, and other variables collected from continuous CTD profiles using CTD and other instruments in the East Coast of the U.S. and Canada during the 2nd East Coast Ocean Acidification (ECOA2, or ECOA-2) cruise from 2018-06-25 to 2018-07-29 (NCEI Accession 0194299). NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/ygfn-av43.
  • Hunt, Christopher W.; Salisbury, Joseph E.; Aßmann, Steffen; Fietzek, Peer; Frank, Carsten; Hare, Jonathan A.; Melrose, Donald C.; Mook, Willem G.; Morrison, J. Ruairidh; Vandemark, Douglas; Wanninkhof, Rik (2020). Underway total alkalinity, temperature and salinity collected from surface seawater during NOAA Ship Henry B. Bigelow ECOA-2 cruise (EXPOCODE 33HH20180625) in the East Coast of the U.S. from 2018-06-25 to 2018-07-29 (NCEI Accession 0215462). NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/82k2-3912.
  • Salisbury, Joseph E.; Shellito, Shawn M.; Cai, Wei-Jun (2023). Dissolved inorganic carbon, total alkalinity, pH, nutrients and other variables collected from discrete profile observations using CTD, Niskin bottle, and other instruments in the East Coast of the U.S. and Canada during the NOAA Ship Ronald H. Brown 3nd East Coast Ocean Acidification (ECOA3, or ECOA-3) cruise (EXPOCODE 33RO20220806) from 2022-08-06 to 2022-09-23 (NCEI Accession 0283329). NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/bkv0-g714.
  • 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: 2019-08-16
  • revision: 2023-05-19
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
Purpose To measure key carbon, physical and biogeochemical parameters in coastal waters of the Gulf of Maine and eastern coast of the US in relation to Ocean Acidification.
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: Salisbury, Joseph E.; Shellito, Shawn M. (2019). Dissolved inorganic carbon, total alkalinity, pH, Oxygen, and other variables collected from surface discrete observations using flow-through pump and other instruments in the East Coast of the U.S. and Canada during the 2nd East Coast Ocean Acidification (ECOA2, or ECOA-2) cruise from 2018-06-26 to 2018-07-28 (NCEI Accession 0196423). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/bh9e-we02. Accessed [date].
Cited Authors
Principal Investigators
Contributors
Resource Providers
Publishers
Acknowledgments
  • Funding Information: NOAA Ocean Acidification Program (East Coast Ocean Acidification Cruise (ECOA) [$560K Total Extramural] - Extramural (Salisbury), OAP1812-1527)
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 Variable Abbreviations
  • ALKALI
  • DIC_AOML
  • PH_TOT
  • TSG SST
  • TSG Sal
  • oxygen
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
Place keywords NODC SEA AREA NAMES THESAURUS Global Change Master Directory (GCMD) Location Keywords
Project keywords NODC PROJECT NAMES THESAURUS Cruise ID
  • HB-18-04 ECOA2
EXPOCODE
  • 33HH20180625
Ocean Acidification Search Keywords
  • Ocean Acidification Program (OAP)
  • Ocean Carbon and Acidification Data System (OCADS) Project
Keywords NCEI ACCESSION NUMBER
Use Constraints
  • Cite as: Salisbury, Joseph E.; Shellito, Shawn M. (2019). Dissolved inorganic carbon, total alkalinity, pH, Oxygen, and other variables collected from surface discrete observations using flow-through pump and other instruments in the East Coast of the U.S. and Canada during the 2nd East Coast Ocean Acidification (ECOA2, or ECOA-2) cruise from 2018-06-26 to 2018-07-28 (NCEI Accession 0196423). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/bh9e-we02. 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
  • 2019-08-16T20:04:19Z - NCEI Accession 0196423 v1.1 was published.
  • 2023-05-19T20:22:28Z - NCEI Accession 0196423 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.
Output Datasets
Lineage information for: dataset
Processing Steps
  • Parameter or Variable: Dissolved Inorganic Carbon; Abbreviation: DIC_AOML; Unit: micromol/kg; Observation type: Surface discrete measurement; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Calculation method and parameters: Calculation of the amount of CO2 injected was according to the CO2 handbook (DOE 1994). The concentration of CO2 ([CO2]) in the samples was determined according to: [CO2] = Cal. Factor * (Counts - Blank * Run Time)* K umol per count / pipette volume * density of sample, where Cal. Factor is the calibration factor, Counts is the instrument reading at the end of the analysis, Blank is the counts/minute determined from blank runs performed at least once for each cell solution, Run Time is the length of coulometric titration (in minutes), and K is the conversion factor from counts to micromoles.; Sampling instrument: Flow through pump; 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 Handbook of Methods for CO2 Analysis (DOE 1994) from the flow-through system 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 for a maximum of 12 hours prior to analysis. The DIC analytical equipment was set up in a seagoing laboratory van. The analysis was done by coulometry with two analytical systems (AOML3 and AOML4) used simultaneously on the cruise. 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- 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 pipette volume was determined by taking aliquots at known temperature of distilled water from the volumes. The weights with the appropriate densities were used to determine the volume of the pipettes. Calculation of the amount of CO2 injected was according to the CO2 handbook (DOE 1994). The instrument has a salinity sensor, but all DIC values were recalculated to a molar weight (umol/kg) using density obtained from the CTD's salinity. The DIC values were corrected for dilution by 0.2 ml of saturated HgCl2 used for sample preservation. 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. The average correction was 2.13 umol/kg. While both systems worked very well during the cruise, they occasionally had high blanks. Normally the blank is less than 30, but we were forced to run them with blanks in the 12-38 range. Several relatively minor problems occurred with AOML 3 during the cruise; (1) A power problem on 06/20/2015 with the coulometer was resolved by plugging several items into different outlets instead of all into the same power strip, (2) Pipette filling problem (liquid level sensor error) which started on 06/28/2015 was resolved on 07/08/2015 by replacing sample tubing and valve/inlet 13, (3) the coulometer was malfunctioning on 07/10/2015 and not responding to the computer/labview program and was switched out with an older version coulometer (AOML5), which was used for the remainder of the cruise, and (4) a field point communication error occurred on 07/16/2015 and was resolved by tightening the serial port connection to DICE 3. AOML 4 worked well during the cruise with no problems. Underway samples were collected from the flow thru system in the Wet Lab during transits between station lines. Discrete DIC samples were collected every hour with duplicates every fifth sample.; Replicate information: Duplicates were collected on most CTD stations and every 5th sample for the underway discrete sampling. A total of 184 duplicates were collected from the discrete CTD samples which had an average difference of 1.09umol/kg and STDEV of 0.77. A total of 44 duplicates were collected for the discrete underway samples which had an average difference of 1.31 umol/kg and STDEV of 0.92. A duplicate data file is included.; 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), Batch 121, supplied by Dr. A. Dickson of SIO, was 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 9-12 hours of continuous use.; CRM manufacturer: Dr. A. Dickson (SIO); 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 1.0007.; Uncertainty: none; 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: DOE (U.S. Department of Energy). (1994). Handbook of Methods for the Analysis of the Various Parameters of the Carbon Dioxide System in Seawater. Version 2.0. ORNL/CDIAC-74. Ed. A. G. Dickson and C. Goyet. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, Oak Ridge, Tenn. 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 67:123-44. 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's 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 21:117-33.; Researcher name: Rik Wanninkhof1, Leticia Barbero1, 2; Researcher institution: Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration 1, University of Miami, CIMAS2.
  • Parameter or Variable: Total alkalinity; Abbreviation: ALKALI; Unit: umol/kg; Observation type: Surface discrete measurement; In-situ / Manipulation / Response variable: in-situ; Measured or calculated: Measured; Sampling instrument: Flow-through pump; Analyzing instrument: Semi-automated total alkalinity titration system (AS-ALK2, Apollo Scitech). This system consists of two high precision Kloehn digital pumps which are equipped with 1 ml and 25 ml syringes, an Orion Star A211 pH meter (Thermo Scientific), and an Orion 8102BN ROSS combination pH electrode (Thermo Scientific), and a thermostated water bath.; Type of titration: Gran titration; Cell type (open or closed): Open; Curve fitting method: Linear least squares regression; Detailed sampling and analyzing information: Samples were measured within 24 hours of collection except for samples collected from station 19, which were poisoned with saturated HgCl2. TA samples were collected directly from the onboard flow-through system into 250 ml ground-glass borosilicate bottles without HgCl2 poisoning. TA was determined on 25 mL seawater samples by potentiometric titration, using 0.1 M hydrochloric acid and an open-cell titration system. All TA samples were analyzed in pre-thermostated glass cells. For each sample analysis, subsamples were sequentially analyzed at least twice until we obtained two replicates with a precision within 0.1%.; Replicate information: 50 duplicates were sampled during the cruise.; Standardization description: The pH electrode was calibrated with three pH buffers (NBS) 4.01, 7.00, and 10.01. Recalibration was done every 12 to 24 hours. The concentration of HCl solution was standardized by the Certified Reference Material (CRM, batch#121 and batch#141). In addition, CRM was also used as sample to check the stability of the TA titration system every 12 hours or when necessary.; Standardization frequency: The concentration of hydrochloric acid was standardized once per day using the Certified Reference Material (CRM).; CRM manufacturer: Dr. A. G. Dickson, Scripps Institution of Oceanography; CRM batch number: Batch#121 and batch#141; Preservation method: N/A; Preservative volume: N/A; Preservative correction: N/A; TA blank correction: N/A; 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: Gran, G. (1952). "Determination of the equivalence point in potentiometric titrations. Part II." Analyst 77(920): 661-671. Cai, W. J., X. P. Hu, W. J. Huang, L. Q. Jiang, Y. C. Wang, T. H. Peng and X. Zhang (2010). "Alkalinity distribution in the western North Atlantic Ocean margins." Journal of Geophysical Research 115: C08014. Huang, W. J., Y. C. Wang and W. J. Cai (2012). "Assessment of sample storage techniques for total alkalinity and dissolved inorganic carbon in seawater." Limnology and Oceanography: Methods 10: 711-717. Dickson, A. G., C. L. Sabine and J. R. Christian (2007). "Guide to Best Practices for Ocean CO2 Measurements."; Researcher name: Wei-Jun Cai; Researcher institution: University of Delaware.
  • Parameter or Variable: pH; Abbreviation: PH_TOT; pH scale: Total; Observation type: Surface discrete measurement; In-situ / Manipulation / Response variable: in-situ; Measured or calculated: Measured; Sampling instrument: Flow through pump; Analyzing instrument: The pH was measured using the spectrophotometric method on the total hydrogen ion concentration pH scale. The analyzing system consists of an Agilent 8453 UV-visible spectroscopy system, a high precision Kloehn digital pump, a 10-cm light path quartz cell, a thermostated water bath, and a custom-made temperature-control system for spectrophotometer cell.; Temperature of pH measurement: 20 C and 25 C. The temperature of measurement for each sample is given under the variable abbreviation "PH_TOT_TEMP".; Detailed sampling and analyzing information: Seawater was sampled directly from the onboard flow-through system into a narrow neck 125 mL borosilicate glass bottle. After filling the bottle, we let several hundred mL of seawater overflow and then capped the bottle. While awaiting analysis, the samples were stored in the dark. Seawater was analyzed within 2 hours of collection. During analysis, the absorbance of a seawater blank was first measured at three wavelengths (578, 434, and 730 nm). Then the absorbance of the mixture of concentrated purified dye m-cresol purple (30 micro-liter, ~2 mmol/L, MCP) and seawater was measured at the same wavelengths. In addition, a double dye addition experiment was carried out at sea to evaluate the influence on pH due to the addition of dye into seawater.; Replicate information: 73 duplicates were sampled during the cruise.; Standardization description: The pH data was guaranteed by purified m-cresol purple which was supplied by Dr. Robert H. Byrne at University of South Florida.; At what temperature was pH reported: 20 C and 25 C. Reported at the temperature of measurement.; Uncertainty: 0.001 pH units; 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. W., M. C. Patsavas and R. H. Byrne (2011). "Purification and Characterization of meta-Cresol Purple for Spectrophotometric Seawater pH Measurements." Environmental Science and Technology 45(11): 4862-4868. Clayton, T. D. and R. H. Byrne (1993). "Spectrophotometric seawater pH measurements - total hydrogen-ion concentration scale calibration of m-cresol purple and at-sea results." Deep-Sea Research Part I 40(10): 2115-2129. Dickson, A. G., C. L. Sabine and J. R. Christian (2007). "Guide to Best Practices for Ocean CO2 Measurements."; Researcher name: Wei-Jun Cai; Researcher institution: University of Delaware.
  • Parameter or Variable: Underway Sea Surface Temp; Abbreviation: TSG SST; Unit: deg c; Observation type: underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Calculation method and parameters: TSG-thermosalinograph; Sampling instrument: SBE 38; Uncertainty: accuracy 0.002 with a percision of 0.0002; 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.; Researcher name: Joe Salisbury; Researcher institution: Ocean Processes Analysis Laboratory, University of New Hampshire.
  • Parameter or Variable: Underway Sea Surface Salinity; Abbreviation: TSG Sal; Unit: PSU; Observation type: underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Calculation method and parameters: TSG-thermosalinograph; Sampling instrument: SBE 45; Uncertainty: accuracy 0.0003 S/m with a precision of 0.0003 S/m; 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.; Researcher name: Joe Salisbury; Researcher institution: Ocean Processes Analysis Laboratory, University of New Hampshire.
  • Parameter or Variable: bottle dissolved oxygen; Abbreviation: oxygen; Unit: umol/kg; Observation type: Surface discrete measurement; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: measured; Sampling instrument: Flow-through pump; Analyzing instrument: Automated oxygen titrator using amperometric end-point detection (Langdon 2010).; Detailed sampling and analyzing information: Samples were drawn from the flow-through system into volumetrically calibrated 125 ml iodine titration flasks using Tygon tubing with a silicone adaptor that fit over the petcock to avoid contamination of DOC samples. Bottles were rinsed three times and filled from the bottom, overflowing three volumes while taking care not to entrain any bubbles. One ml of MnCl2 and one ml of NaOH/NaI were added immediately after drawing of the sample was concluded using a Repipetor, the flasks were then stoppered and shaken well. DIW was added to the neck of each flask to create a water seal. The flasks were stored in the lab in plastic totes at room temperature for at least 1 hour before analysis. Twenty-four samples plus duplicates were drawn from each station except the shallow coastal stations where fewer samples were drawn depending on the depth or as directed by the chief scientist. Dissolved oxygen analyses were performed with an automated oxygen titrator using amperometric end-point detection (Langdon 2010). The titration of the samples and the data logging and graphical display was performed on a PC running a LabView program written by Ulises Rivero of AOML. The titrations were performed in a climate controlled lab at 18.5-20 degrees Celsius. Thiosulfate was dispensed by a 2 ml Gilmont syringe driven with a stepper motor controlled by the titrator. Tests in the lab were performed to confirm that the precision and accuracy of the volume dispensed were comparable or superior to the Dosimat 665. The whole-bottle titration technique of Carpenter (1965) with modifications by Culberson et al. (1991) was used. Four to three replicate 10 ml iodate standards were run 13 times during the cruise. The reagent blank was determined at the beginning and end of the cruise. A titration was made to 1 ml of iodate standard. The volume of thiosulfate required for the titration is V1. An additional 1 ml of standard was added to the titrated sample and titrated again. The volume of thiosulfate used for the second titration is V2. The reagent blank was determined as the difference between V1 and V2.; 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: Carpenter, J.H. (1965). The Chesapeake Bay Institute technique for the Winkler dissolved oxygen method. Limnol. Oceanogr. 10: 141-143 Culberson, C.H. and Huang, S. (1987). Automated amperometric oxygen titration. Deep-Sea Res. 34: 875-880. Culberson, C.H.; Knapp, G.; Stalcup, M.; Williams, R.T. and Zemlyak, F. (1991). A comparison of methods for the determination of dissolved oxygen in seawater. WHP Operations and Methods. Langdon, C. (2010). Determination of dissolved oxygen in seawater by Winkler titration using the amperometric technique. The GO-SHIP Repeat Hydrography Manual: A Collection of Expert Reports and Guidelines. E. M. Hood, C. L. Sabine and B. M. Sloyan, IOCCP Report Number 14, ICPO Publication Series Number 134.; Researcher name: Chris Langdon; Researcher institution: Rosenstiel School of Marine and Atmospheric Science/University of Miami .
Acquisition Information (collection)
Instrument
  • Flow-through pump
Platform
  • NOAA Ship Henry B. Bigelow
Last Modified: 2024-03-09T06:51:28Z
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