| Processing Steps |
- Parameter or Variable: Dissolved Inorganic Carbon; Abbreviation: DIC; Unit: umol kg-1; Observation type: Profile (discrete samples); In-situ / Manipulation / Response variable: in-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle; Analyzing instrument: AIRICA; Detailed sampling and analyzing information: The Automated Infra Red Inorganic Carbon Analyzer (AIRICA) by Marianda paired with a LiCOR LI-7000 Automated CO2 Analyzer was used to conduct an IR-detection of carbon dioxide with a carrier gas. Data flags: 1 = not calibrated, 2 = good, 3 = questionable, 4 = bad, 5 = not reported, 6 = interpolated over > 2 dbar interval, 7 = despiked, 8 = not assigned for CTD data, 9 = not sampled; Standardization description: The samples were standardized using Certified Reference Materials (CRMs) provided by Dr. A. Dickson of Scripps Institution of Oceanography.; Standardization frequency: Daily; CRM manufacturer: UCSD; CRM batch number: 185, 190; Preservation method: HgCl2; Preservative volume: Saturated, 200 uL; Preservative correction: none; Uncertainty: 2 umol kg-1; Quality flag convention: Data flags: 1 = not calibrated, 2 = good, 3 = questionable, 4 = bad, 5 = not reported, 6 = interpolated over > 2 dbar interval, 7 = despiked, 8 = not assigned for CTD data, 9 = not sampled; Method reference: Mathis, J.T., J.N. Cross, W. Evans, and S.C. Doney. 2015. Ocean acidification in the surface waters of the Pacific-Arctic boundary regions. Oceanography 28(2):122-135, https://doi.org/10.5670/ oceanog.2015.36.; Researcher name: Natalie Monacci; Researcher institution: UAF.
- Parameter or Variable: Total alkalinity; Abbreviation: TA; Unit: umol kg-1; Observation type: Profile (discrete samples); In-situ / Manipulation / Response variable: in-situ observation; Measured or calculated: Measured; Sampling instrument: Niskin bottle; Analyzing instrument: VINDTA; Type of titration: Potentiometric; Cell type (open or closed): open; Curve fitting method: GRAN plot; Detailed sampling and analyzing information: The Versatile INstrument for the Determination of Total inorganic and titration of Alkalinity (VINDTA) by Marianda was used to conduct a potentiometric alkalinity titration with an open cell.; Standardization description: The samples were standardized using Certified Reference Materials (CRMs) provided by Dr. A. Dickson of Scripps Institution of Oceanography.; Standardization frequency: Daily; CRM manufacturer: UCSD; CRM batch number: 185, 190; Preservation method: HgCl2; Preservative volume: Saturated, 200 uL; Preservative correction: none; Uncertainty: 2 umol kg-1; Quality flag convention: Data flags: 1 = not calibrated, 2 = good, 3 = questionable, 4 = bad, 5 = not reported, 6 = interpolated over > 2 dbar interval, 7 = despiked, 8 = not assigned for CTD data, 9 = not sampled; Method reference: Mathis, J. T., Cross, J. N., Bates, N. R., Bradley Moran, S., Lomas, M. W., Mordy, C. W., and Stabeno, P. J. 2010. Seasonal distribution of dissolved inorganic carbon and net community production on the Bering and Chukchi Sea shelf, Biogeosciences, 7, 1769-1787, https://doi.org/10.5194/bg-7-1769-2010.; Researcher name: Natalie Monacci; Researcher institution: UAF.
- Parameter or Variable: CTD Temperature; Abbreviation: CTDTEMP_ITS90; Unit: DEG C (ITS-90); Observation type: Profile (CTD continuous); In-situ / Manipulation / Response variable: in-situ observation; Measured or calculated: Measured; Sampling instrument: CTD (conductivity, temperature and depth); Detailed sampling and analyzing information: A profiling CTD 911 was used to collect the conductivity, temperature, and depth data at each station. Data are processed using Seabird CTD software and calibration file. Post-processing at WHOI includes filtering extreme outliers, extrapolation of values from the top value collected at ~3-5m to the surface. Each cast is visually reviewed for reasonableness and density inversions (greater than 0.02 sigma-t) caused by spurious measurements. This process is facilitated by comparison of the outputs of the 2 temperature and conductivity sensors. Profile data are bin-averaged to 1 meter.; Uncertainty: 0.002; Quality flag convention: Data flags: 1 = not calibrated, 2 = good, 3 = questionable, 4 = bad, 5 = not reported, 6 = interpolated over > 2 dbar interval, 7 = despiked, 8 = not assigned for CTD data, 9 = not sampled; Researcher name: Leah McRaven; Researcher institution: WHOI.
- Parameter or Variable: CTD Salinity; Abbreviation: CTDSAL_PSS78; Unit: PSU (PSS-78); Observation type: Profile (CTD continuous); Measured or calculated: Calculated; Sampling instrument: CTD (conductivity, temperature and depth); Detailed sampling and analyzing information: A profiling CTD 911 was used to collect the conductivity, temperature, and depth data at each station. Data are processed using Seabird CTD software and calibration file. Post-processing at WHOI includes filtering extreme outliers, extrapolation of values from the top value collected at ~3-5m to the surface. Each cast is visually reviewed for reasonableness and density inversions (greater than 0.02 sigma-t) caused by spurious measurements. This process is facilitated by comparison of the outputs of the 2 temperature and conductivity sensors. Profile data are bin-averaged to 1 meter.; Uncertainty: 0.002; Quality flag convention: Data flags: 1 = not calibrated, 2 = good, 3 = questionable, 4 = bad, 5 = not reported, 6 = interpolated over > 2 dbar interval, 7 = despiked, 8 = not assigned for CTD data, 9 = not sampled; Researcher name: Leah McRaven; Researcher institution: WHOI.
- Parameter or Variable: Salinity; Abbreviation: Salinity_PSS78; Observation type: Profile (discrete samples); Sampling instrument: Niskin bottle; Analyzing instrument: Guildline Salinometer model 8400 B; Detailed sampling and analyzing information: Water was collected in 200 ml glass bottles. The bottles were rinsed three times, and then filled to the neck. After the samples reached the lab temperature of approximately 20 ̊ C, they were analyzed for salinity using a Guildline Salinometer model 8400 B. The salinometer’s bath temperature was set to 21 ̊ C and was standardized before and after each run using IAPSO Standard Seawater (batch 171). Accuracies of salinity measurements were ±0.002 psu when a good standardization was achieved. Bottle salinities were assigned a quality control flag based upon the difference between CTD salinity (calibrated) at the same pressure and/or at the same potential temperature.; Uncertainty: 0.002; Quality flag convention: Data flags: 1 = not calibrated, 2 = good, 3 = questionable, 4 = bad, 5 = not reported, 6 = interpolated over > 2 dbar interval, 7 = despiked, 8 = not assigned for CTD data, 9 = not sampled; Researcher name: Leah McRaven; Researcher institution: WHOI.
- Parameter or Variable: CTD Oxygen; Abbreviation: CTDOXY; Unit: umol kg-1; Observation type: Profile (CTD continuous); Sampling instrument: CTD (conductivity, temperature and depth); Detailed sampling and analyzing information: In situ data was collected from a profiling CTD 911 paied with a SBE 43 to collect dissolved oxygen data. Data were originally processed to filter out extreme outliers and reviewed for reasonableness, along with other profile data.; Uncertainty: 1 umol kg-1; Quality flag convention: Data flags: 1 = not calibrated, 2 = good, 3 = questionable, 4 = bad, 5 = not reported, 6 = interpolated over > 2 dbar interval, 7 = despiked, 8 = not assigned for CTD data, 9 = not sampled; Researcher name: Leah McRaven; Researcher institution: WHOI.
- Parameter or Variable: Dissolved oxygen (DO); Abbreviation: Oxygen; Unit: umol kg-1; Observation type: Profile (discrete samples); Measured or calculated: Measured; Sampling instrument: Niskin bottle; Detailed sampling and analyzing information: To calibrate O2 sensor data, we collected bottle samples for dissolved O2 concentration from the surface underway (n=35) and select CTD casts (n=62). These samples were analyzed onboard using automated amperometric titration.; Uncertainty: 1 umol kg-1; Quality flag convention: Data flags: 1 = not calibrated, 2 = good, 3 = questionable, 4 = bad, 5 = not reported, 6 = interpolated over > 2 dbar interval, 7 = despiked, 8 = not assigned for CTD data, 9 = not sampled; Researcher name: Laurie Juranek; Researcher institution: OSU.
- Parameter or Variable: Silicate; Abbreviation: Silicate; Unit: umol kg-1; Observation type: Profile (discrete samples); Sampling instrument: Niskin bottle; Analyzing instrument: Seal Analytical continuous-flow AutoAnalyzer 3 (AA3); Detailed sampling and analyzing information: Nutrient analyses (phosphate, silicate, nitrate+nitrite, and nitrite) were performed on a Seal Analytical continuous-flow AutoAnalyzer 3 (AA3). The methods used are described by Gordon et al [Gordon1992]_ Hager et al. [Hager1972]_, and Atlas et al. [Atlas1971]_. Details of modification of analytical methods used in this cruise are also compatible with the methods described in the nutrient section of the updated GO-SHIP repeat hydrography manual (Becker et al., 2019, [Becker 2019]_. 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. Sampling Nutrient samples were drawn into 30 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 16 hours after sample collection, allowing sufficient time for all samples to reach room temperature. The centrifuge tubes fit directly onto the sampler. Data Collection and Processing Data collection and processing was done with the software provided with the instrument from Seal Analytical (AACE). After each run, the charts were reviewed for any problems during the run, any blank was subtracted, and final concentrations (micro moles/liter) were calculated, based on a linear curve fit. Once the run was reviewed and concentrations calculated a text file was created. That text file was reviewed for possible problems and then converted to another text file with only sample identifiers and nutrient concentrations that was merged with other bottle data.; Quality flag convention: Data flags: 1 = not calibrated, 2 = good, 3 = questionable, 4 = bad, 5 = not reported, 6 = interpolated over > 2 dbar interval, 7 = despiked, 8 = not assigned for CTD data, 9 = not sampled; Method reference: Becker, S., Aoyama M., Woodward M., Baaker, K., Covery, S., Mahaffey, C., Tanhua, T., "GO-SHIP Repeat Hydrography Nutrient Manual, 2019: The Precise and accurate determination of dissololved inorganic nutrients in seawater;Continuos Flow Analysis methods. Ocean Best Practices, August 2019: https://doi.org/10.25607/OBP-555; Researcher name: Susan Becker; Researcher institution: UCSD.
- Parameter or Variable: Phosphate (PO4 3-); Abbreviation: Phosphate; Unit: umol kg-1; Observation type: Profile (discrete samples); Measured or calculated: Measured; Sampling instrument: Niskin bottle; Analyzing instrument: Seal Analytical continuous-flow AutoAnalyzer 3 (AA3); Detailed sampling and analyzing information: Nutrient analyses (phosphate, silicate, nitrate+nitrite, and nitrite) were performed on a Seal Analytical continuous-flow AutoAnalyzer 3 (AA3). The methods used are described by Gordon et al [Gordon1992]_ Hager et al. [Hager1972]_, and Atlas et al. [Atlas1971]_. Details of modification of analytical methods used in this cruise are also compatible with the methods described in the nutrient section of the updated GO-SHIP repeat hydrography manual (Becker et al., 2019, [Becker 2019]_. Phosphate Analysis Ortho-Phosphate was analyzed using a modification of the Bernhardt and Wilhelms (1967) [Bernhardt1967]_ method. Acidified ammonium molybdate was added to a seawater sample to produce phosphomolybdic acid, which was then reduced to phosphomolybdous acid (a blue compound) following the addition of dihydrazine sulfate. The sample was passed through a 10mm flowcell and absorbance measured at 820nm. Sampling Nutrient samples were drawn into 30 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 16 hours after sample collection, allowing sufficient time for all samples to reach room temperature. The centrifuge tubes fit directly onto the sampler. Data Collection and Processing Data collection and processing was done with the software provided with the instrument from Seal Analytical (AACE). After each run, the charts were reviewed for any problems during the run, any blank was subtracted, and final concentrations (micro moles/liter) were calculated, based on a linear curve fit. Once the run was reviewed and concentrations calculated a text file was created. That text file was reviewed for possible problems and then converted to another text file with only sample identifiers and nutrient concentrations that was merged with other bottle data.; Quality flag convention: Data flags: 1 = not calibrated, 2 = good, 3 = questionable, 4 = bad, 5 = not reported, 6 = interpolated over > 2 dbar interval, 7 = despiked, 8 = not assigned for CTD data, 9 = not sampled; Method reference: Becker, S., Aoyama M., Woodward M., Baaker, K., Covery, S., Mahaffey, C., Tanhua, T., "GO-SHIP Repeat Hydrography Nutrient Manual, 2019: The Precise and accurate determination of dissololved inorganic nutrients in seawater;Continuos Flow Analysis methods. Ocean Best Practices, August 2019: https://doi.org/10.25607/OBP-555; Researcher name: Susan Becker; Researcher institution: UCSD.
- Parameter or Variable: Nitrate (NO3-); Abbreviation: Nitrate; Unit: umol kg-1; Observation type: Profile (discrete samples); Measured or calculated: Measured; Sampling instrument: Niskin bottle; Analyzing instrument: Seal Analytical continuous-flow AutoAnalyzer 3 (AA3); Detailed sampling and analyzing information: Nutrient analyses (phosphate, silicate, nitrate+nitrite, and nitrite) were performed on a Seal Analytical continuous-flow AutoAnalyzer 3 (AA3). The methods used are described by Gordon et al [Gordon1992]_ Hager et al. [Hager1972]_, and Atlas et al. [Atlas1971]_. Details of modification of analytical methods used in this cruise are also compatible with the methods described in the nutrient section of the updated GO-SHIP repeat hydrography manual (Becker et al., 2019, [Becker 2019]_. Nitrate/Nitrite Analysis 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 520nm. The procedure was the same for the nitrite analysis but without the cadmium column. Sampling Nutrient samples were drawn into 30 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 16 hours after sample collection, allowing sufficient time for all samples to reach room temperature. The centrifuge tubes fit directly onto the sampler. Data Collection and Processing Data collection and processing was done with the software provided with the instrument from Seal Analytical (AACE). After each run, the charts were reviewed for any problems during the run, any blank was subtracted, and final concentrations (micro moles/liter) were calculated, based on a linear curve fit. Once the run was reviewed and concentrations calculated a text file was created. That text file was reviewed for possible problems and then converted to another text file with only sample identifiers and nutrient concentrations that was merged with other bottle data.; Quality flag convention: Data flags: 1 = not calibrated, 2 = good, 3 = questionable, 4 = bad, 5 = not reported, 6 = interpolated over > 2 dbar interval, 7 = despiked, 8 = not assigned for CTD data, 9 = not sampled; Method reference: Becker, S., Aoyama M., Woodward M., Baaker, K., Covery, S., Mahaffey, C., Tanhua, T., "GO-SHIP Repeat Hydrography Nutrient Manual, 2019: The Precise and accurate determination of dissololved inorganic nutrients in seawater;Continuos Flow Analysis methods. Ocean Best Practices, August 2019: https://doi.org/10.25607/OBP-555; Researcher name: Susan Becker; Researcher institution: UCSD.
- Parameter or Variable: Nitrite (NO2-); Abbreviation: Nitrite; Unit: umol kg-1; Observation type: Profile (discrete samples); Measured or calculated: Measured; Sampling instrument: Niskin bottle; Analyzing instrument: Seal Analytical continuous-flow AutoAnalyzer 3 (AA3); Detailed sampling and analyzing information: Nutrient analyses (phosphate, silicate, nitrate+nitrite, and nitrite) were performed on a Seal Analytical continuous-flow AutoAnalyzer 3 (AA3). The methods used are described by Gordon et al [Gordon1992]_ Hager et al. [Hager1972]_, and Atlas et al. [Atlas1971]_. Details of modification of analytical methods used in this cruise are also compatible with the methods described in the nutrient section of the updated GO-SHIP repeat hydrography manual (Becker et al., 2019, [Becker 2019]_. Nitrate/Nitrite Analysis 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 520nm. The procedure was the same for the nitrite analysis but without the cadmium column. Sampling Nutrient samples were drawn into 30 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 16 hours after sample collection, allowing sufficient time for all samples to reach room temperature. The centrifuge tubes fit directly onto the sampler. Data Collection and Processing Data collection and processing was done with the software provided with the instrument from Seal Analytical (AACE). After each run, the charts were reviewed for any problems during the run, any blank was subtracted, and final concentrations (micro moles/liter) were calculated, based on a linear curve fit. Once the run was reviewed and concentrations calculated a text file was created. That text file was reviewed for possible problems and then converted to another text file with only sample identifiers and nutrient concentrations that was merged with other bottle data.; Method reference: Becker, S., Aoyama M., Woodward M., Baaker, K., Covery, S., Mahaffey, C., Tanhua, T., "GO-SHIP Repeat Hydrography Nutrient Manual, 2019: The Precise and accurate determination of dissololved inorganic nutrients in seawater;Continuos Flow Analysis methods. Ocean Best Practices, August 2019: https://doi.org/10.25607/OBP-555 .
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