| Processing Steps |
- Parameter or Variable: Dissolved Inorganic Carbon; Abbreviation: tcarbn; Unit: micro-mol/kg; Observation type: Profile and surface underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle and 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 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 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 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 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 (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. 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 2.3 micro-mol/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 to 45 range. Other problems were relatively minor. The Midas failed shortly after the cruise began so compressed Nitrogen was used for sample analysis. Communication errors between the instruments and their controlling laptop computers occurred several times. Coulometer AOML 5 was replaced with Coulometer AOML 3 on DICE 3 the second to last day during the GOM line of stations. Underway samples were collected from the flow thru system in the Wet Lab during transits between station lines. Discrete DIC samples were collected every two hours with duplicates every fourth sample.; Replicate information: Duplicates were collected on every station as well as on the underway discrete sampling; 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), Batches 112 and 120, supplied by Dr. A. Dickson of SIO, 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 (SIO); CRM batch number: 112 and 120; 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.; 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 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.
- Parameter or Variable: Total alkalinity; Abbreviation: alkali; Unit: micro-mol/kg; Observation type: Profile and surface underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle and flow through pump; Analyzing instrument: Semi-automatic titration system (AS-ALK2, Apollo Scitech), consisting of two KloehnTM syringe pumps (module #50300) of 1 ml and 25 ml respectively, a pH meter (AR15, Accumet Research), and a ROSS combination pH glass electrode (Orion 8102BN, Thermo Scientific).; Type of titration: Gran titration; Cell type (open or closed): Open; Curve fitting method: End point; Detailed sampling and analyzing information: All of the samples were measured in 48 hours except 86 samples were poisoned with 40 micro liter saturated HgCl2 for later, post-cruise analysis at the UGA lab. TA samples were taken by 250ml narrow-ground neck, borosilicate glass bottles from Niskin bottles after removing air bubbles from the sampling tubing. Each glass bottle was rinsed three times and then filled from the bottom (overflow of half of bottle volume seawater was allowed). One ml headspace was left for those post-cruise-analysis samples and no headspace was left for those measured on board.; Replicate information: 10 duplicates were sampled during the cruise.; Standardization description: For each measurement, 25 ml of TA sample was titrated with an HCl solution (0.1 M HCl and 0.5 M NaCl). This TA titration system has a precision of better than 0.1 % (Cai et al. 2010). pH electrode was calibrated with pH buffer (NBS) 4.01, 7.00, and 10.01 and recalibration was done every 12 to 24 hours. All the TA values were directly measured with reference to Certified Reference Material (CRM, batch#114). System (titrator and electrode) stability was also checked along with the sample run using the CRM seawater every 12 hours or when necessary. The precision of this method is better than 0.1% and accuracy is 0.1%.; Standardization frequency: All values were directly measured with reference to Certified Reference Material (Dickson, SIO); CRM manufacturer: Dr. A. Dickson (SIO); Preservation method: 86 samples were poisoned with 40 micro liter saturated HgCl2 for later, post-cruise analysis at the UGA lab. The other samples were not poisoned.; Preservative volume: 40 microliters; 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 2. The analyst, 77, 661-671.; Researcher name: Wei-Jun Cai; Researcher institution: University of Georgia.
- Parameter or Variable: pH; Abbreviation: PH_TOT; pH scale: Total; Observation type: Profile and surface underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle and flow through pump; Analyzing instrument: Agilent 8453 spectrometer setup with a custom-made temperature-controlled cell holder; Temperature of pH measurement: 25 (minus plus 0.05) degrees Celsius; Detailed sampling and analyzing information: Samples were collected for pH analysis immediately following O2 in the Niskin/Rosette sampling sequence. Seawater samples were collected from the Niskin bottles directly in 10-cm cylindrical optical cells (~30 mL volume) using a section of silicone tubing (about 15 cm long). One end of the silicone tubing was attached to the optical cell and the other end was attached to the nipple of the Niskin bottle. The Niskin bottle nipple was pushed in to initiate flow and the silicone tubing was squeezed to eliminate air bubbles. The optical cell was agitated to eliminate bubbles and, after 15 seconds of sample flow, the cell was capped at one end. The silicone tubing was then detached from the optical cell and, with the water still flowing, the cap was rinsed and used to seal the optical cell. Samples collected this way were not exposed to the atmosphere, and each cell was flushed with approximately three cell volumes of seawater. The samples were collected, taken into the lab, and rinsed with tap water to get rid of salt outside of the cells. The cells were dried and the optical windows were cleaned with Kimwipes. Samples were thermostatted at 25 (minus plus 0.05) degrees Celsius in a custom made 36-position cell warmer. A custom macro program running on Agilent ChemStation was used to guide the measurements and data processing. The macro automated the procedures of sample input, blank and sample scans, quality control, and data archiving. The quality control steps included checking the baseline shift after dye injection and monitoring the standard deviation of multiple scans. 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. pHT (total scale) was calculated according to Liu et al. (2011); Replicate information: Duplicate pH samples were collected from underway samples (N = 105) and from discrete samples taken from the Niskin bottles (N = ~60) with a precision equal to minus plus 0.0004.; Standardization description: The pH is calibration-free.; At what temperature was pH reported: 25 degrees Celsius; Uncertainty: Precision was equal to minus plus 0.0004.; 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: Robert Byrne; Researcher institution: University of South Florida.
- Parameter or Variable: pCO2 (fCO2) discrete; Abbreviation: fCO2; Unit: micro-atmospheres; Observation type: Profile and surface underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle and flow through pump; Analyzing instrument: LI-COR (model 840); Storage method: The sample bottles were sealed with glass stoppers lightly covered with Apiezon-L grease and were stored at room temperature for a maximum of twelve hours prior to analysis. When twelve bottles were moved into the primary water bath for analyses, the next twelve bottles were moved into the secondary water bath. No sample bottle spent less than one hour in the secondary water bath prior to being moved to the analytical water bath.; Seawater volume: 500 ml; Headspace volume: 5 ml; Temperature of measurement: 20 degrees Celsius; Detailed sampling and analyzing information: Samples were drawn from 10-L Niskin bottles into 500 ml glass bottles using Tygon tubing with a Silicone adapter that fit over the drain cock to avoid contamination of DOM samples. Bottles were rinsed twice, the second time while inverted. They were filled from the bottom, overflowing half a volume while taking care not to entrain any bubbles. About 5 ml of water was withdrawn to allow for expansion of the water as it warms and to provide space for the stopper and tubing of the analytical system. Saturated mercuric chloride solution (0.2 ml) 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 twelve hours prior to analysis.The analyses for pCO2 were done with the discrete samples at 20 degrees Celsius. A primary water bath was kept within 0.03 degrees Celsius of the analytical temperature; a secondary bath was kept within 0.15 degrees Celsius the analytical temperature. The majority of the samples were analyzed in batches of twelve bottles, which with standards took approximately 2.5 hours. When twelve bottles were moved into the primary water bath for analyses, the next twelve bottles were moved into the secondary water bath. No sample bottle spent less than one hour in the secondary water bath prior to being moved to the analytical water bath.; Sample replicate information: More than fifty sets of duplicate bottles were drawn at numerous depths. The average relative error of these duplicate pairs was 0.18%, while the median relative error was 0.11%.; Gas detector manufacturer: LiCOR infrared analyzer. The system was built by Colm Sweeney and Tim Newberger; Gas detector model: Prototype; Gas detector uncertainty: The average relative error of these duplicate pairs was 0.18%, while the median relative error was 0.11%.; Standardization technique: To ensure analytical accuracy, a set of six gas standards (ranging from 248 to 1534 ppm) was run through the analyzer before and after every sample batch. The standards were obtained from Scott-Marin and referenced against primary standards purchased from C.D. Keeling in 1991, which are on the WMO-78 scale.; Standardization frequency: Before and after each batch of 12 samples.; Standard gas manufacturer: Scott Marin; Standard gas concentration: 248.73, 384.14, 567.40, 792.51, 1036.95, and 1533.7 ppm; Water vapor correction method: The details of the data reduction are described in Pierrot, et.al. (2009).; Temperature correction method: The details of the data reduction are described in Pierrot, et.al. (2009).; At what temperature was pCO2 reported: 20 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: Wanninkhof, R.; and Thoning, K. (1993). Measurement of fugacity of CO2 in surface water using continuous and discrete sampling methods. Mar. Chem., v. 44, no. 2-4, pp. 189-205. Pierrot, D.; Neill, C.; Sullivan, K.; Castle, R.; Wanninkhof, R.; Lüger, H.; Johannessen, T.; Olsen, A.; Feely, R.A.; and Cosca, C.E. (2009). Recommendations for autonomous underway pCO2 measuring systems and data-reduction routines. Deep-Sea Res., II, v. 56, pp. 512-522.; Researcher name: Rik Wanninkhof; Researcher institution: Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration.
- Parameter or Variable: CTD pressure; Abbreviation: CTDPRS; Unit: dbars; Observation type: profile; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: CTD; Analyzing instrument: Sea-Bird SBE-911plus CTD system; Detailed sampling and analyzing information: A detailed and more complete description is available in the cruise report at: http://www.aoml.noaa.gov/ocd/gcc/GOMECC2/Cruise_Report.pdf. CTD/rosette casts were performed with a package consisting of a 24-place, 10-liter rosette frame (AOML white frame), a 24-place water sampler/pylon (SBE32) and 24, 10-liter Bullister/Niskin-style bottles. This package was deployed on all stations/casts. Underwater electronic components consisted of a Sea-Bird Electronics (SBE) 9 plus CTD with dual pumps and the following sensors: dual temperature (SBE3), dual conductivity (SBE4), dual dissolved oxygen (SBE43), and a Simrad 807 altimeter. The CTDs supplied a standard Sea-Bird format data stream at a data rate of 24 frames/second. The SBE9plus CTD was connected to the SBE32 24-place pylon providing for single-conductor sea cable operation. Power to the SBE9plus CTD, SBE32 pylon, auxiliary sensors, and altimeter was provided through the sea cable from the SBE11plus deck unit in the computer lab. Shipboard CTD data processing was performed automatically at the end of each deployment using SEABIRD SBE Data Processing version 7.21h and AOML Matlab processing software.; Uncertainty: Pressure sensor calibration coefficients derived from the pre-cruise calibrations were applied to raw pressure data during each cast. Residual pressure offsets (the difference between the first and last submerged pressures) were examined to check for calibration shifts. On deck pressure before the start of each cast was recorded. The on deck pressure before and after the cast were stable at 1.67 +/- 0.081 db, and 1.68 +/- 0.087 db respectively. Near surface pressure values (which are taken as the near-surface pressure at the markscan and the last fired bottle pressure) showed relatively small variability (4.41+/- 0.40 db before and 4.54+/- 0.33 db after).; Method reference: http://www.aoml.noaa.gov/ocd/gcc/GOMECC2/Cruise_Report.pdf.; Researcher name: Molly Baringer; Researcher institution: Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration.
- Parameter or Variable: CTD temperature; Abbreviation: CTDTMP; Unit: degree C; Observation type: profile; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: CTD; Analyzing instrument: Sea-Bird SBE-911plus CTD system; Detailed sampling and analyzing information: A detailed and more complete description is available in the cruise report at: http://www.aoml.noaa.gov/ocd/gcc/GOMECC2/Cruise_Report.pdf. CTD/rosette casts were performed with a package consisting of a 24-place, 10-liter rosette frame (AOML white frame), a 24-place water sampler/pylon (SBE32) and 24, 10-liter Bullister/Niskin-style bottles. This package was deployed on all stations/casts. Underwater electronic components consisted of a Sea-Bird Electronics (SBE) 9 plus CTD with dual pumps and the following sensors: dual temperature (SBE3), dual conductivity (SBE4), dual dissolved oxygen (SBE43), and a Simrad 807 altimeter. The CTDs supplied a standard Sea-Bird format data stream at a data rate of 24 frames/second. The SBE9plus CTD was connected to the SBE32 24-place pylon providing for single-conductor sea cable operation. Power to the SBE9plus CTD, SBE32 pylon, auxiliary sensors, and altimeter was provided through the sea cable from the SBE11plus deck unit in the computer lab. Shipboard CTD data processing was performed automatically at the end of each deployment using SEABIRD SBE Data Processing version 7.21h and AOML Matlab processing software.; Uncertainty: Temperature sensor calibration coefficients derived from the pre-cruise calibrations were applied to raw primary and secondary temperature data during each cast. Calibration accuracy was examined by comparing T1-T2 over a range of station numbers and pressures (bottle trip locations) for each cast. For the entire cruise, only one set of temperature sensors were used, both tracked each other extremely nicely. The median temperature difference between the two sensors was 0.0006 degrees Celsius with a pseudo standard deviation of 0.006 degrees Celsius.; Method reference: http://www.aoml.noaa.gov/ocd/gcc/GOMECC2/Cruise_Report.pdf.; Researcher name: Molly Baringer; Researcher institution: Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration.
- Parameter or Variable: CTD salinity; Abbreviation: CTDSAL; Observation type: profile; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Calculated from conductivity measurements.; Sampling instrument: CTD; Analyzing instrument: Sea-Bird SBE-911plus CTD system; Detailed sampling and analyzing information: A detailed and more complete description is available in the cruise report at: http://www.aoml.noaa.gov/ocd/gcc/GOMECC2/Cruise_Report.pdf. CTD/rosette casts were performed with a package consisting of a 24-place, 10-liter rosette frame (AOML white frame), a 24-place water sampler/pylon (SBE32) and 24, 10-liter Bullister/Niskin-style bottles. This package was deployed on all stations/casts. Underwater electronic components consisted of a Sea-Bird Electronics (SBE) 9 plus CTD with dual pumps and the following sensors: dual temperature (SBE3), dual conductivity (SBE4), dual dissolved oxygen (SBE43), and a Simrad 807 altimeter. The CTDs supplied a standard Sea-Bird format data stream at a data rate of 24 frames/second. The SBE9plus CTD was connected to the SBE32 24-place pylon providing for single-conductor sea cable operation. Power to the SBE9plus CTD, SBE32 pylon, auxiliary sensors, and altimeter was provided through the sea cable from the SBE11plus deck unit in the computer lab. Shipboard CTD data processing was performed automatically at the end of each deployment using SEABIRD SBE Data Processing version 7.21h and AOML Matlab processing software.; Uncertainty: Conductivity sensor calibration coefficients derived from the pre-cruise calibrations were applied to raw primary and secondary conductivities. Comparisons between the primary and secondary sensors and between each of the sensors to check sample conductivities (conductivity calculated from bottle salinities) were used to derive conductivity corrections. For the entire cruise, only one set of conductivity sensors were used, both tracked each other extremely nicely. The two sensors show a median difference of 0.00092 S/m and a pseudo standard deviation of 0.00064 S/m.; Quality flag convention: WOCE quality control flags are used: 2 = good value, 3 = questionable value, 4 = bad value.; Method reference: http://www.aoml.noaa.gov/ocd/gcc/GOMECC2/Cruise_Report.pdf.; Researcher name: Molly Baringer; Researcher institution: Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration.
- Parameter or Variable: Theta; Abbreviation: Theta; Unit: degree C; Observation type: profile; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Calculated; Sampling instrument: CTD.
- Parameter or Variable: Sigma theta; Abbreviation: SigmaTheta; Observation type: profile; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Calculated; Sampling instrument: CTD.
- Parameter or Variable: Bottle salinity; Abbreviation: SALNTY; Observation type: Profile; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle; Analyzing instrument: Guildline Autosal, model 8400B salinometer (S/N 60843); Detailed sampling and analyzing information: The salinity samples were collected in 200 ml Kimax high-alumina borosilicate bottles that had been rinsed at least three times with sample water prior to filling. The bottles were sealed with custom-made plastic insert thimbles and Nalgene screw caps. This assembly provides very low container dissolution and sample evaporation. Prior to sample collection, inserts were inspected for proper fit and loose inserts replaced to insure an airtight seal. Laboratory temperature was also monitored electronically throughout the cruise. PSS-78 salinity UNES81, was calculated for each sample from the measured conductivity ratios. The offset between the initial standard seawater value and its reference value was applied to each sample. The difference (if any) between the initial and final vials of standard seawater was then applied to each sample as a linear function of elapsed run time. Salinity analyses were performed after samples had equilibrated to laboratory temperature, usually at least 24 hours after collection. The salinometer was standardized for each group of samples analyzed (usually 2 casts and up to 50 samples) using two bottles of standard seawater: one at the beginning and end of each set of measurements. The salinometer output was logged to a computer file. The software prompted the analyst to flush the instrument cell and change samples when appropriate. For each sample, the salinometer cell was initially flushed at least 3 times before a set of conductivity ratio readings were taken.; Replicate information: A duplicate sample was drawn from each cast to determine total analytical precision.; Uncertainty: Through the course of the 24-day cruise, the autosal standards changed by 0.0001 in conductivity ratio (about 0.008 in salinity).; 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: Molly Baringer; Researcher institution: Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration.
- Parameter or Variable: CTD oxygen; Abbreviation: CTDOXY; Unit: micro-mol/kg; Observation type: profile; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: CTD; Analyzing instrument: Sea-Bird SBE-911plus CTD system; Detailed sampling and analyzing information: A detailed and more complete description is available in the cruise report at: http://www.aoml.noaa.gov/ocd/gcc/GOMECC2/Cruise_Report.pdf. CTD/rosette casts were performed with a package consisting of a 24-place, 10-liter rosette frame (AOML white frame), a 24-place water sampler/pylon (SBE32) and 24, 10-liter Bullister/Niskin-style bottles. This package was deployed on all stations/casts. Underwater electronic components consisted of a Sea-Bird Electronics (SBE) 9 plus CTD with dual pumps and the following sensors: dual temperature (SBE3), dual conductivity (SBE4), dual dissolved oxygen (SBE43), and a Simrad 807 altimeter. The CTDs supplied a standard Sea-Bird format data stream at a data rate of 24 frames/second. The SBE9plus CTD was connected to the SBE32 24-place pylon providing for single-conductor sea cable operation. Power to the SBE9plus CTD, SBE32 pylon, auxiliary sensors, and altimeter was provided through the sea cable from the SBE11plus deck unit in the computer lab. Shipboard CTD data processing was performed automatically at the end of each deployment using SEABIRD SBE Data Processing version 7.21h and AOML Matlab processing software.; Uncertainty: Two SBE43 dissolved O2 (DO) sensors were used on this cruise. Both sensors tracked each other very well, with no noted problems. The DO sensors were calibrated to dissolved O2 check samples by matching the up cast bottle trips to down cast CTD data along isopycnal surfaces, calculating CTD dissolved O2, and then minimizing the residuals using a non-linear least-squares fitting procedure. The fitting determined calibration coefficients for the sensor model conversion equation and proceeded in a series of steps. Each sensor was fit in a separate sequence. The first step was to determine the time constants for the exponential terms in the model. These time constants are sensor-specific but applicable to an entire cruise. Once the time constants had been determined, casts were fit individually to O2 check sample data. The resulting calibration coefficients were then smoothed and held constant during a refit to determine sensor slope and offset. Calibration accuracy was examined by comparing O1-O2 over a range of station numbers and pressures (bottle trip locations) for each cast. For the entire cruise, only one set of oxygen sensors were used, both tracked each other extremely nicely. The two sensors show a median difference of -2.96 micro-mol/kg and a pseudo standard deviation of 1.21 micro-mol/kg.; Method reference: http://www.aoml.noaa.gov/ocd/gcc/GOMECC2/Cruise_Report.pdf.; Researcher name: Molly Baringer; Researcher institution: Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration.
- Parameter or Variable: bottle dissolved oxygen; Abbreviation: oxygen; Unit: micro-mol/kg; Observation type: Profile and surface underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle and flow through pump; Analyzing instrument: Automated oxygen titrator using amperometric end-point detection (Langdon 2010).; Detailed sampling and analyzing information: Samples were drawn from all casts and all Niskin bottles 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. The draw temperature was taken using a digital thermometer with a flexible thermistor probe that was inserted into the flask while the sample was being drawn during the overflow period. These temperatures were used to calculate concentrations, and a diagnostic check of Niskin bottle integrity. 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.; Replicate information: Over 100 duplicate samples were drawn. The preliminary difference between replicates averaged 0.2 micro-mol kg-1 for stations 1-93.; 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.
- Parameter or Variable: Orthosilicic acid; Abbreviation: silcat; Unit: micro-mol/kg; Observation type: Profile and surface underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle and flow through pump; Analyzing instrument: Continuous flow analyzer (CFA) using the standard and analysis protocols for the WOCE hydrographic program as set forth in the manual by L.I. Gordon, et al. (1993).; Detailed sampling and analyzing information: Nutrient samples were collected from Niskin bottles, after at least three seawater rinses. Sample analysis typically began within a few hours of sample collection after the samples had warmed to room temperature. Those samples not analyzed within 3 hours were refrigerated for later analysis. Samples were analyzed for phosphate (PO4- 3), nitrate (NO3-), nitrite (NO2-) and orthosilicic acid (H4SiO4). Silicic acid was analyzed using a modification of Armstrong et al. (1967). The sample is reacted with ammonium molybdate in an acidic solution to form molybdosilicic acid. The molybdosilicic acid was then reduced with ascorbic acid to form molybdenum blue. The absorbance of the molybdenum blue was measured at 660 nm.; Uncertainty: A mixed stock standard consisting of silicic acid, phosphate and nitrate was prepared by dissolving high purity standard materials (KNO3, KH2PO4 and Na2SiF6) in deionized water using a two step dilution for phosphate and nitrate. This standard was stored at room temperature. A nitrite stock standard was prepared dissolving NaNO2 in distilled water, and this standard was stored in a refrigerator on the ship. Working standards were prepared fresh daily by diluting the stock solutions in low nutrient seawater. The mixed standards were verified against commercial standards, and in-lab standards.; 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: Armstrong, F.A.J., Stearns, C.R. and Strickland, J.D.H. (1967). The measurement of upwelling and subsequent biological processes by means of the Technicon AutoAnalyzer and associated equipment. Deep-Sea Res. 14:381-389. Gordon, L.I., Jennings Jr., J.C., Ross, A.A. and Krest, J.M. (1993). A suggested protocol for the continuous automated analysis of seawater nutrients (phosphate, nitrate, nitrite and silicic acid) in the WOCE Hydrographic program and the Joint Global Ocean Fluxes Study. WOCE Operations Manual, vol. 3: The Observational Programme, Section 3.2: WOCE Hydrographic Programme, Part 3.1.3: WHP Operations and Methods. WHP Office Report WHPO 91-1; WOCE Report No. 68/91. November 1994, Revision 1, Woods Hole, MA., USA, 52 loose-leaf pages.; Researcher name: Jia-Zhong Zhang; Researcher institution: Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration.
- Parameter or Variable: Nitrite; Abbreviation: nitrit; Unit: micro-mol/kg; Observation type: Profile and surface underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle and flow through pump; Analyzing instrument: Continuous flow analyzer (CFA) using the standard and analysis protocols for the WOCE hydrographic program as set forth in the manual by L.I. Gordon, et al. (1993).; Detailed sampling and analyzing information: Nutrient samples were collected from Niskin bottles, after at least three seawater rinses. Sample analysis typically began within a few hours of sample collection after the samples had warmed to room temperature. Those samples not analyzed within 3 hours were refrigerated for later analysis. Samples were analyzed for phosphate (PO4- 3), nitrate (NO3-), nitrite (NO2-) and orthosilicic acid (H4SiO4). Nitrite was determined by diazotizing the sample with sulfanilamide and coupling with N-1 naphthyl ethylenediamine dihydrochloride to form an azo dye. The color produced is measured at 540 nm.; Uncertainty: A mixed stock standard consisting of silicic acid, phosphate and nitrate was prepared by dissolving high purity standard materials (KNO3, KH2PO4 and Na2SiF6) in deionized water using a two step dilution for phosphate and nitrate. This standard was stored at room temperature. A nitrite stock standard was prepared dissolving NaNO2 in distilled water, and this standard was stored in a refrigerator on the ship. Working standards were prepared fresh daily by diluting the stock solutions in low nutrient seawater. The mixed standards were verified against commercial standards, and in-lab standards.; 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: Armstrong, F.A.J., Stearns, C.R. and Strickland, J.D.H. (1967). The measurement of upwelling and subsequent biological processes by means of the Technicon AutoAnalyzer and associated equipment. Deep-Sea Res. 14:381-389. Gordon, L.I., Jennings Jr., J.C., Ross, A.A. and Krest, J.M. (1993). A suggested protocol for the continuous automated analysis of seawater nutrients (phosphate, nitrate, nitrite and silicic acid) in the WOCE Hydrographic program and the Joint Global Ocean Fluxes Study. WOCE Operations Manual, vol. 3: The Observational Programme, Section 3.2: WOCE Hydrographic Programme, Part 3.1.3: WHP Operations and Methods. WHP Office Report WHPO 91-1; WOCE Report No. 68/91. November 1994, Revision 1, Woods Hole, MA., USA, 52 loose-leaf pages.; Researcher name: Jia-Zhong Zhang; Researcher institution: Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration.
- Parameter or Variable: nitrate; Abbreviation: nitrat; Unit: micro-mol/kg; Observation type: Profile and surface underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle and flow through pump; Analyzing instrument: Continuous flow analyzer (CFA) using the standard and analysis protocols for the WOCE hydrographic program as set forth in the manual by L.I. Gordon, et al. (1993).; Detailed sampling and analyzing information: Nutrient samples were collected from Niskin bottles, after at least three seawater rinses. Sample analysis typically began within a few hours of sample collection after the samples had warmed to room temperature. Those samples not analyzed within 3 hours were refrigerated for later analysis. Samples were analyzed for phosphate (PO4- 3), nitrate (NO3-), nitrite (NO2-) and orthosilicic acid (H4SiO4). Samples for nitrate analysis were passed through a cadmium column, which reduced nitrate to nitrite, and the resulting nitrite concentration (i.e. the sum of nitrate + nitrite which is signified as N+N) was then determined as described above. Nitrate concentrations were determined from the difference of N+N and nitrite.; Uncertainty: A mixed stock standard consisting of silicic acid, phosphate and nitrate was prepared by dissolving high purity standard materials (KNO3, KH2PO4 and Na2SiF6) in deionized water using a two step dilution for phosphate and nitrate. This standard was stored at room temperature. A nitrite stock standard was prepared dissolving NaNO2 in distilled water, and this standard was stored in a refrigerator on the ship. Working standards were prepared fresh daily by diluting the stock solutions in low nutrient seawater. The mixed standards were verified against commercial standards, and in-lab standards.; 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: Armstrong, F.A.J., Stearns, C.R. and Strickland, J.D.H. (1967). The measurement of upwelling and subsequent biological processes by means of the Technicon AutoAnalyzer and associated equipment. Deep-Sea Res. 14:381-389. Gordon, L.I., Jennings Jr., J.C., Ross, A.A. and Krest, J.M. (1993). A suggested protocol for the continuous automated analysis of seawater nutrients (phosphate, nitrate, nitrite and silicic acid) in the WOCE Hydrographic program and the Joint Global Ocean Fluxes Study. WOCE Operations Manual, vol. 3: The Observational Programme, Section 3.2: WOCE Hydrographic Programme, Part 3.1.3: WHP Operations and Methods. WHP Office Report WHPO 91-1; WOCE Report No. 68/91. November 1994, Revision 1, Woods Hole, MA., USA, 52 loose-leaf pages.; Researcher name: Jia-Zhong Zhang; Researcher institution: Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration.
- Parameter or Variable: Sum of nitrate + nitrite; Abbreviation: NO2+NO3; Unit: micro-mol/kg; Observation type: Profile and surface underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle and flow through pump; Analyzing instrument: Continuous flow analyzer (CFA) using the standard and analysis protocols for the WOCE hydrographic program as set forth in the manual by L.I. Gordon, et al. (1993).; Detailed sampling and analyzing information: Nutrient samples were collected from Niskin bottles, after at least three seawater rinses. Sample analysis typically began within a few hours of sample collection after the samples had warmed to room temperature. Those samples not analyzed within 3 hours were refrigerated for later analysis. Samples were analyzed for phosphate (PO4- 3), nitrate (NO3-), nitrite (NO2-) and orthosilicic acid (H4SiO4). Samples were passed through a cadmium column, which reduced nitrate to nitrite, and the resulting nitrite concentration (i.e. the sum of nitrate + nitrite which is signified as N+N) was then determined as described above.; Uncertainty: A mixed stock standard consisting of silicic acid, phosphate and nitrate was prepared by dissolving high purity standard materials (KNO3, KH2PO4 and Na2SiF6) in deionized water using a two step dilution for phosphate and nitrate. This standard was stored at room temperature. A nitrite stock standard was prepared dissolving NaNO2 in distilled water, and this standard was stored in a refrigerator on the ship. Working standards were prepared fresh daily by diluting the stock solutions in low nutrient seawater. The mixed standards were verified against commercial standards, and in-lab standards.; 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: Armstrong, F.A.J., Stearns, C.R. and Strickland, J.D.H. (1967). The measurement of upwelling and subsequent biological processes by means of the Technicon AutoAnalyzer and associated equipment. Deep-Sea Res. 14:381-389. Gordon, L.I., Jennings Jr., J.C., Ross, A.A. and Krest, J.M. (1993). A suggested protocol for the continuous automated analysis of seawater nutrients (phosphate, nitrate, nitrite and silicic acid) in the WOCE Hydrographic program and the Joint Global Ocean Fluxes Study. WOCE Operations Manual, vol. 3: The Observational Programme, Section 3.2: WOCE Hydrographic Programme, Part 3.1.3: WHP Operations and Methods. WHP Office Report WHPO 91-1; WOCE Report No. 68/91. November 1994, Revision 1, Woods Hole, MA., USA, 52 loose-leaf pages.; Researcher name: Jia-Zhong Zhang; Researcher institution: Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration.
- Parameter or Variable: phosphate; Abbreviation: phspht; Unit: micro-mol/kg; Observation type: Profile and surface underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle and flow through pump; Analyzing instrument: Continuous flow analyzer (CFA) using the standard and analysis protocols for the WOCE hydrographic program as set forth in the manual by L.I. Gordon, et al. (1993).; Detailed sampling and analyzing information: Nutrient samples were collected from Niskin bottles, after at least three seawater rinses. Sample analysis typically began within a few hours of sample collection after the samples had warmed to room temperature. Those samples not analyzed within 3 hours were refrigerated for later analysis. Samples were analyzed for phosphate (PO4- 3), nitrate (NO3-), nitrite (NO2-) and orthosilicic acid (H4SiO4). Phosphate was determined by reacting the sample with molybdic acid to form phosphomolybdic acid. This complex was subsequently reduced with hydrazine, and the absorbance of the resulting phosphomolybdous acid was measured at 710 nm.; Uncertainty: A mixed stock standard consisting of silicic acid, phosphate and nitrate was prepared by dissolving high purity standard materials (KNO3, KH2PO4 and Na2SiF6) in deionized water using a two step dilution for phosphate and nitrate. This standard was stored at room temperature. A nitrite stock standard was prepared dissolving NaNO2 in distilled water, and this standard was stored in a refrigerator on the ship. Working standards were prepared fresh daily by diluting the stock solutions in low nutrient seawater. The mixed standards were verified against commercial standards, and in-lab standards.; 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: Armstrong, F.A.J., Stearns, C.R. and Strickland, J.D.H. (1967). The measurement of upwelling and subsequent biological processes by means of the Technicon AutoAnalyzer and associated equipment. Deep-Sea Res. 14:381-389. Gordon, L.I., Jennings Jr., J.C., Ross, A.A. and Krest, J.M. (1993). A suggested protocol for the continuous automated analysis of seawater nutrients (phosphate, nitrate, nitrite and silicic acid) in the WOCE Hydrographic program and the Joint Global Ocean Fluxes Study. WOCE Operations Manual, vol. 3: The Observational Programme, Section 3.2: WOCE Hydrographic Programme, Part 3.1.3: WHP Operations and Methods. WHP Office Report WHPO 91-1; WOCE Report No. 68/91. November 1994, Revision 1, Woods Hole, MA., USA, 52 loose-leaf pages.; Researcher name: Jia-Zhong Zhang; Researcher institution: Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration.
- Parameter or Variable: total nitrate (N2 + N3); Abbreviation: TN_RSMAS; Unit: micro-mol/kg; Observation type: Profile; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle; 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: Dennis Hansell; Researcher institution: Rosenstiel School of Marine and Atmospheric Science/University of Miami.
- Parameter or Variable: carbonate ion concentration; Abbreviation: CO3; Unit: micro-mol/kg; Observation type: Profile and surface underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle and flow through pump; Analyzing instrument: Agilent 8453 spectrometer setup with a custom-made temperature-controlled cell holder.; Detailed sampling and analyzing information: The carbonate ion samples were sampled into quartz cells in the same manner as the pH samples. After the pH samples were taken, the quartz cells were attached to the silicone tubing to collect samples for carbonate ion concentration measurements. Samples were analyzed on an Agilent 8453 spectrophotometer. A UV blank was taken for each sample and 20 micro liter of 0.022 M PbClO4 were added (Acros Organics, Lot A0301399 - 99% purity). Absorbances, A, were measured at two wavelengths (234 nm and 250 nm), along with the absorbance at a non-absorbing wavelength (350 nm).; Replicate information: Duplicates were drawn at each station and for underway discrete measurements.; Uncertainty: All spectrophotometric pH and CO32- measurements were tentatively flagged if the baseline shifted more than 0.002 absorbance units for pH and 0.004 absorbance units for carbonate ion measurements. A series of at least three spectra were averaged for each determination and samples were rerun if the overall standard deviations were higher than 0.0004 for pH measurements and 0.002 for carbonate ion measurements. This process was repeated until the standard deviation of multiple readings was within 0.0004 for pH and 0.002 for carbonate. Absorbance values were saved so that the quality criteria can be evaluated in the future. Data for directly measured carbonate are reported in terms of both concentrations and the R-Ratios taken at 250 nm and 234 nm. Data for both CO32-, and pH are reported at the analysis temperature of 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: Byrne, R.H.; and Yao, W. (2008). Procedures for measurement of carbonate ion concentrations in seawater by direct spectrophotometric observations of Pb(II) complexation. Marine Chemistry, 112(1-2), 128-135. Clayton, T.D.; and Byrne, R.H. (1993). Spectrophotometric seawater pH measurements: total hydrogen ion concentration scale calibration of m-cresol purple and at-sea results. Deep Sea Research Part I: Oceanographic Research Papers, 40(10), 2115-2129. https://doi.org/10.1016/0967-0637(93)90048-8 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: Robert Byrne; Researcher institution: University of South Florida.
- Parameter or Variable: Total Organic Carbon; Abbreviation: TOC; Unit: micro-mol/kg; Observation type: Profile; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle; Detailed sampling and analyzing information: Forty ml of unfiltered seawater were collected into PC bottles, frozen upright in the onboard walk-in freezer at -16 degrees Celsius, and stored frozen for shipment. In total, 598 samples were collected. These are complementary to the samples collected by UNH for DOC/CDOM/Chla analysis. At stations where samples were collected for both RSMAS and UNH analyses, duplication occurred at the surface and bottom depths. At shallow stations (water depths ~50 m), TOC samples were not collected by RSMAS since they were collected by UNH.; 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: Dennis Hansell; Researcher institution: Rosenstiel School of Marine and Atmospheric Science/University of Miami.
- Parameter or Variable: Dissolved Organic Carbon; Abbreviation: DOC_UNH; Unit: micro-mol/kg; Observation type: Profile; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle; Detailed sampling and analyzing information: Samples were taken from the surface, near bottom (isopyctal), and where applicable at a second depth in the mixed layer. The samples were run through 47mm GFF filters and separated into 2 or 3 (depending on depth) 40ml vials for DOC and one 125ml bottle for CDOM. The DOC vials were frozen and the CDOM bottles refrigerated. DOC and CDOM samples were analyzed by a laboratory of Antonio Mannino at NASA Goddard. Additionally, samples for POC were taken several times per day from the outflow of the tank. These were filtered using precombusted GFF filters by colleague Sumit Chakraborty (USM). The filters were stored in liquid nitrogen and brought back to UNH where a subset of samples were analyzed.; 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: University of New Hampshire.
- Parameter or Variable: Colored dissolved organic matter at different wavelengths; Abbreviation: CDOM; Unit: micro-mol/kg; Observation type: Profile; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle; Detailed sampling and analyzing information: Samples were taken from the surface, near bottom (isopyctal), and where applicable at a second depth in the mixed layer. The samples were run through 47mm GFF filters and separated into 2 or 3 (depending on depth) 40ml vials for DOC and one 125ml bottle for CDOM. The DOC vials were frozen and the CDOM bottles refrigerated. DOC and CDOM samples were analyzed by a laboratory of Antonio Mannino at NASA Goddard. Additionally, samples for POC were taken several times per day from the outflow of the tank. These were filtered using precombusted GFF filters by colleague Sumit Chakraborty (USM). The filters were stored in liquid nitrogen and brought back to UNH where a subset of samples were analyzed.; 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: University of New Hampshire.
- Parameter or Variable: Phytoplankton pigments: Total Chlorophyll-a, Total Chlorophyll-b, Total Chlorophyll-c, Alpha-beta-carotene, butanoyloxyfucoxanthin, hexanoyloxyfuco-xanthin, Alloxanthin, Diadinoxanthin, Diatoxanthin, Fucoxanthin, Peridinin, Zeaxanthin, monovinyl chlorophyll a, divinyl chlorophyll a, chlorophyllide a, monovinyl chlorophyll b, divinyl chlorophyll b, Chlorophyll c12, Chlorophyll c3, Lutein, Neoxanthin, Violaxanthin, total pheophytin a, total pheophorbide a, Prasinoxanthin.; Abbreviation: Tot_Chl_a, Tot_Chl_b, Tot_Chl_c, Alpha_beta_Car, But fuco, Hex fuco, Allo, Diadino, Diato, Fuco, Perid, Zea, MV_Chl_a, DV_Chl_a, Chlide_a, MV_Chl _b, DV_Chl_b, Chl c12, Chl_c3, Lut, Neo, Viola, Phytin_a, Phide_a, Pras; Unit: mg/m3; Observation type: Profile; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle; Detailed sampling and analyzing information: During the cruise, seawater (2-4 L) for pigment analysis was collected at selected depths (based on the fluorescence profile) from 10 L Niskin bottles on a rosette and was immediately filtered onto Whatman 47mm GF/F filters using a vacuum pump less than 0.5 atm. The filters were blotted dry and frozen in 2 ml cryotubes in liquid nitrogen till analysis on land. The phytoplankton pigment analysis will follow the method described in Van Heukelem and Thomas (2001).; Method reference: Van Heukelem, L.; and Thomas, C.S. (2001). Computer-assisted high-performance liquid chromatography method development with applications to the isolation and analysis of phytoplankton pigments. Journal of Chromatography A 910:31-49; Researcher name: Steven Lohrenz; Researcher institution: University of Massachusetts-Dartmouth.
- Parameter or Variable: Calcium; Abbreviation: CaUGA; Observation type: Profile; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle; Researcher name: Wei-Jun Cai; Researcher institution: University of Georgia.
- Parameter or Variable: DNA; Abbreviation: DNA; Observation type: Profile; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle; Researcher name: Steven Lohrenz; Researcher institution: University of Massachusetts-Dartmouth.
- Parameter or Variable: Total suspended particles; Abbreviation: TSS; Observation type: Profile; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle; Researcher name: Steven Lohrenz; Researcher institution: University of Massachusetts-Dartmouth.
- Parameter or Variable: Particulate absorption; Abbreviation: ap; Observation type: Profile; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Researcher name: Steven Lohrenz; Researcher institution: University of Massachusetts-Dartmouth .
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