Processing Steps |
- Parameter or Variable: Dissolved Inorganic Carbon; Abbreviation: DIC; Unit: umol kg-1; Observation type: Surface underway measurement; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: Pump seawater from underway system; Analyzing instrument: Two Picarro Cavity Ring-Down Spectroscopy instruments; Detailed sampling and analyzing information: The method is based on dual isotope dilution and cavity ring-down spectroscopy (DID-CRDS). In this method, seawater is continuously sampled and mixed with a flow of NaH13CO3 solution that is also enriched in deuterated water (the spike). The isotopic composition of CO2 (delta 13C spiked_sample) derived from the DIC in the mixture, and the D/H ratio of the mixed water (delta D spiked_sample), are measured by CRDS analyzers. The D/H of the water in the mixture allows accurate estimates of the mixing ratio of the sample and the spike. [DIC] of the sample is then calculated from the mixing ratio, [DI13C] of the spike, and delta 13C spiked_sample.; Uncertainty: less than 0.03%; Quality flag convention: 2: good data 3.Questionable data; Method reference: An Ultrahigh Precision, High-Frequency Dissolved Inorganic Carbon Analyzer Based on Dual Isotope Dilution and Cavity Ring-Down Spectroscopy Kuan Huang, Nicolas Cassar, Bror Jonsson, Wei-jun Cai, and Michael L. Bender Environmental Science and Technology 2015 49 (14), 8602-8610 https://doi.org/10.1021/acs.est.5b01036; Researcher name: Bror Jonsson; Researcher institution: University of New Hampshire.
- Parameter or Variable: pH; Abbreviation: PH_RAW, PH_TOT; pH scale: NBS, Total; Observation type: Surface underway; In-situ / Manipulation / Response variable: in-situ; Measured or calculated: measured; Analyzing instrument: Honeywell Durafet III Non-Glass pH electrode with Vario Pin Connector; Temperature of pH measurement: In engine room, ~2 m after the seachest, before the seawater pumps, SBE-38; Detailed sampling and analyzing information: Raw output of pH (in NBS scale) was presented without a calibration. Spectrophotometric pH analyses on discrete samples were used for the calibration of raw data. Corrected pH = Measured pH + delta pH, where delta pH = Spec pH (total, at Durafet temperature) - Durafet pH (NBS scale, at water temperature in the flow through cell) = -0.005268 X Temperature + 0.01551. Slope and intercept came from the linear regression of delta pH and the water temperature in the flow through cell. Then the pH at sea surface temperature condition was calculated via CO2SYS using SST and SSS from SBE 38 and SBE 45 and the total alkalinity estimated from the linear relationship with SSS (TA_EST = 49.027 X SSS + 598.73, R2 = 0.98, this relationship was developed from the discrete surface bottle samples collected from the ECOA cruise).; Researcher name: Yuan-Yuan Xu; Researcher institution: University of Delaware.
- Parameter or Variable: sea surface salinity; Abbreviation: SSS; Observation type: Surface underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: measured; Sampling instrument: SBE-45.
- Parameter or Variable: sea surface temperature; Abbreviation: SST; Unit: degree c; Observation type: Surface underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: measured; Sampling instrument: SBE-45.
- Parameter or Variable: pH measurement temperature; Abbreviation: MEASUREMENT_Temp; Unit: degree c; Observation type: Surface underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: measured; Sampling instrument: Honeywell Durafet III Non-Glass pH electrode with Vario Pin Connector.
- Parameter or Variable: O2/Ar superaturation; Abbreviation: delta_O2Ar; Unit: no; Observation type: Surface underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: Measured; Sampling instrument: pump seawater from underway system; Analyzing instrument: Equilibrium inlet mass spectrometer (EIMS); Detailed sampling and analyzing information: water flowed constantly at 100 ml/min through a gas-permeable membrane contraction cartridge (MicroModuel, Liqui-Cel Membrane). Equilibrated gasses diffused into a fused-silica capillary (2 m in length and 0.05 mm in diameter) that connects to a quadruple mass spectrometer (Pfeiffer vacuum) for ion current intensity and ratio measurements. Calibration was conducted automatically every 3 hours for 20-min using ambient air, which has a stable O2/Ar. The analysis procedure for O2Ar: 1. Remove abnormal data due to instrument stop, unacceptable pressure, and unstable flow rate; 2. Remove 8-min data (e-folding time) after switching between air and water inlets; 3. In every 2-min, O2 Ar ratio were measured about 120 times. Only data within 95% confidence interval were averaged; 4. delta_O2Ar = [(O2/Ar)warter - (O2/Ar)air]/(O2/Ar)air; Uncertainty: precision of EIMS: plus/minus 0.2%; Quality flag convention: 2: good data 3.Questionable data; Method reference: Cassar, N., B. A. Barnett, M. L. Bender, J. Kaiser, R. C. Hamme, and B. Tilbrook. 2009. Continuous high-frequency dissolved O2/Ar measurements by equilibrator inlet mass spectrometry. Anal. Chem. 81: 1855-1864.; Researcher name: Yonghui Gao; Researcher institution: University of Delaware.
- Parameter or Variable: oxygen saturation (%) of underway seawater; Abbreviation: Optode_DO; Unit: %; Observation type: Surface underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: measured; Sampling instrument: pump seawater from underway system; Analyzing instrument: an optode dissolved oxygen sensor (Aanderaa 4135); Detailed sampling and analyzing information: The oxygen optode is based on the dynamic luminescence quenching technique, and can measure DO% and temperature at frequency of 30second.Underway water flowed constantly as that for O2/Ar ratio measurement; The DO% were calibrated with oxygen water samples, which were taken from underway water and measured with winkler titration method.; Uncertainty: absolute accuracy is better than plus/minus 1.5%; Quality flag convention: 1. unmeasurement 2. good 3. questionable data; Method reference: TD 269 operating mannual: oxygen optode 4430, 4831, 4835. Feb 2014, AADI: 2-84; Researcher name: Yonghui Gao; Researcher institution: University of Delaware.
- Parameter or Variable: Water temperature of underway samples (C); Abbreviation: Optode_Temp; Unit: degree c; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: measured; Sampling instrument: pump seawater from underway system; Analyzing instrument: an optode dissolved oxygen sensor (Aanderaa 4135); Detailed sampling and analyzing information: The oxygen optode is based on the dynamic luminescence quenching technique, and can measure DO% and temperature at frequency of 30second. Underway water flowed constantly as that for O2/Ar ratio measurement; The DO% were calibrated with oxygen water samples, which were taken from underway water and measured with winkler titration method.; Uncertainty: absolute accuracy is better than plus/minus 1.5%; Quality flag convention: 1. unmeasurement 2. good 3. questionable data; Method reference: TD 269 operating mannual: oxygen optode 4430, 4831, 4835. Feb 2014, AADI: 2-84; Researcher name: Yonghui Gao; Researcher institution: University of Delaware.
- Parameter or Variable: Correction of DO% of underway seawater; Abbreviation: Cor_Optode; Unit: %; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: measured; Sampling instrument: pump seawater from underway system; Analyzing instrument: an optode dissolved oxygen sensor (Aanderaa 4135); Detailed sampling and analyzing information: The oxygen optode is based on the dynamic luminescence quenching techonique, and can measure DO% and temperature at frequency of 30second. Underway water flowed constantly as that for O2/Ar ratio measurement; The DO% were calibrated with oxygen water samples, which were taken from underway water and measured with winkler titration method; Uncertainty: absolute accuracy is better than plus/minus 1.5%; Quality flag convention: 1. unmeasurement 2. good 3. questionable data; Method reference: TD 269 operating mannual: oxygen optode 4430, 4831, 4835. Feb 2014, AADI: 2-84; Researcher name: Yonghui Gao; Researcher institution: University of Delaware.
- Parameter or Variable: Oxygen solubility of underway water; Abbreviation: O2_solubility; Unit: %; Observation type: Surface underway; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: measured; Sampling instrument: pump seawater from underway system; Analyzing instrument: an optode dissolved oxygen sensor (Aanderaa 4135); Detailed sampling and analyzing information: The oxygen optode is based on the dynamic luminescence quenching techonique, and can measure DO% and temperature at frequency of 30second. Solubility were calculated based on salinity and temperature; Uncertainty: absolute accuracy is better than plus/minus 1.5%; Quality flag convention: 1. unmeasurement 2. good 3. questionable data; Method reference: TD 269 operating mannual: oxygen optode 4430, 4831, 4835. Feb 2014, AADI: 2-84; Researcher name: Yonghui Gao; Researcher institution: University of Delaware.
- Parameter or Variable: correction of DO% of underway seawater; Abbreviation: DO; Unit: %; In-situ / Manipulation / Response variable: In-situ observation; Measured or calculated: measured; Sampling instrument: pump seawater from underway system; Analyzing instrument: an optode dissolved oxygen sensor (Aanderaa 4135); Detailed sampling and analyzing information: Sample correction with bottle samples: The team member of Chris Longdon took oxygen underway samples and measured with winkler titration for DO concentration; we use underway oxygen solubility and [DO] to calculate DO% and correct the drift in oxygen sensor; Uncertainty: absolute accuracy is better than plus/minus 1.5%; Quality flag convention: 1. unmeasurement 2. good 3. questionable data; Method reference: TD 269 operating mannual: oxygen optode 4430, 4831, 4835. Feb 2014, AADI: 2-84; Researcher name: Yonghui Gao; Researcher institution: University of Delaware .
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