AMT6 Dissolved Inorganic Carbon (DIC) concentrations from CTD bottle samples
Originator's Protocol for Data Acquisition and Analysis
This data originates from analyses on samples collected from 27 stations during the cruise. Samples were taken from up to 12 bottles fired during the morning casts.
DIC was measured by coulometric titration (Robinson and Williams, 1991; Doe, 1994). Analysis of seawater DIC reference materials throughout the cruise provided quality assessment of the precision and accuracy of the DIC measurements. A surface water samples was collected using a bucket at the same time as CTD44 for analysis.
References Cited
Doe, 1994. Handbook of methods for the analysis of the various parameters of the carbon dioxide system in seawater; version 2. A.G. Dickson and C. Goyet (eds.) ORNL/CDIAC-74
Robinson C. and Williams P.J.Leb., 1991. Development and assessment of an analystical system for the accurate and continual measurement of total dissolved inorganic carbon. Marine Chemistry, 34, 157-175.
Instrumentation Description
Not applicable for this data set.
BODC Data Processing Procedures
Data were submitted with the AMT6 dissolved oxygen concentration and saturation dataset in an Excel spreadsheet archived under BODC's accession number PML030011. Sample metadata (CTD cast, date, latitude, longitude and depth) were checked against information held in the database. There were no discrepancies.
The concentration data were provided in millimoles per cubic metre. These units for the concentration data were equivalent to the BODC parameter code units (micro-moles per litre), so no unit conversions were applied.
The data were reformatted and loaded in BODC's samples database under Oracle Relational Database Management System. Data were marked up with BODC parameter codes and loaded into the database. Individual samples were matched by depth for each cast.
A parameter mapping table is provided below;
Originator's Parameter | Units | Description | BODC Parameter Code | Units | Comments |
---|---|---|---|---|---|
DIC | mmol m -3 | Concentration of carbon (total inorganic) {TCO2} per unit volume of the water body [dissolved plus reactive particulate phase] by coulometry | TCO2CBTX | µmol l -1 | n/a |
Data Quality Report
The data originator highlighted two samples where the DIC data were suspect - these have been flagged 'L' in the database. The data originator also suspected H 2 S interference during A6-12 (CTD12). These data have not been flagged.
Problem Report
Not relevant to this data set.