Metadata Report for BODC Series Reference Number 1868454
Metadata Summary
Problem Reports
Data Access Policy
Narrative Documents
Project Information
Data Activity or Cruise Information
Fixed Station Information
BODC Quality Flags
SeaDataNet Quality Flags
Metadata Summary
Data Description |
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Data Identifiers |
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Time Co-ordinates(UT) |
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Spatial Co-ordinates | |||||||||||||||||||||||||
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Parameters |
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Definition of BOTTFLAG | |||||||||||||||||||||||||
BOTTFLAG | Definition |
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0 | The sampling event occurred without any incident being reported to BODC. |
1 | The filter in an in-situ sampling pump physically ruptured during sample resulting in an unquantifiable loss of sampled material. |
2 | Analytical evidence (e.g. surface water salinity measured on a sample collected at depth) indicates that the water sample has been contaminated by water from depths other than the depths of sampling. |
3 | The feedback indicator on the deck unit reported that the bottle closure command had failed. General Oceanics deck units used on NERC vessels in the 80s and 90s were renowned for reporting misfires when the bottle had been closed. This flag is also suitable for when a trigger command is mistakenly sent to a bottle that has previously been fired. |
4 | During the sampling deployment the bottle was fired in an order other than incrementing rosette position. Indicative of the potential for errors in the assignment of bottle firing depth, especially with General Oceanics rosettes. |
5 | Water was reported to be escaping from the bottle as the rosette was being recovered. |
6 | The bottle seals were observed to be incorrectly seated and the bottle was only part full of water on recovery. |
7 | Either the bottle was found to contain no sample on recovery or there was no bottle fitted to the rosette position fired (but SBE35 record may exist). |
8 | There is reason to doubt the accuracy of the sampling depth associated with the sample. |
9 | The bottle air vent had not been closed prior to deployment giving rise to a risk of sample contamination through leakage. |
Definition of Rank |
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Problem Reports
No Problem Report Found in the Database
Data Access Policy
Public domain data
These data have no specific confidentiality restrictions for users. However, users must acknowledge data sources as it is not ethical to publish data without proper attribution. Any publication or other output resulting from usage of the data should include an acknowledgment.
The recommended acknowledgment is
"This study uses data from the data source/organisation/programme, provided by the British Oceanographic Data Centre and funded by the funding body."
Narrative Documents
Niskin Bottle
The Niskin bottle is a device used by oceanographers to collect subsurface seawater samples. It is a plastic bottle with caps and rubber seals at each end and is deployed with the caps held open, allowing free-flushing of the bottle as it moves through the water column.
Standard Niskin
The standard version of the bottle includes a plastic-coated metal spring or elastic cord running through the interior of the bottle that joins the two caps, and the caps are held open against the spring by plastic lanyards. When the bottle reaches the desired depth the lanyards are released by a pressure-actuated switch, command signal or messenger weight and the caps are forced shut and sealed, trapping the seawater sample.
Lever Action Niskin
The Lever Action Niskin Bottle differs from the standard version, in that the caps are held open during deployment by externally mounted stainless steel springs rather than an internal spring or cord. Lever Action Niskins are recommended for applications where a completely clear sample chamber is critical or for use in deep cold water.
Clean Sampling
A modified version of the standard Niskin bottle has been developed for clean sampling. This is teflon-coated and uses a latex cord to close the caps rather than a metal spring. The clean version of the Levered Action Niskin bottle is also teflon-coated and uses epoxy covered springs in place of the stainless steel springs. These bottles are specifically designed to minimise metal contamination when sampling trace metals.
Deployment
Bottles may be deployed singly clamped to a wire or in groups of up to 48 on a rosette. Standard bottles and Lever Action bottles have a capacity between 1.7 and 30 L. Reversing thermometers may be attached to a spring-loaded disk that rotates through 180° on bottle closure.
Dissolved and Colloidal Organic Carbon for cruises Belgica BG9309 and BG9322
Document History
Converted from CDROM documentation.
Content of data series
CORGNOD3 | Dissolved organic carbon |
High temperature Ni catalytic oxidation (GF/C filtered) | |
Micromoles/litre | |
CORGCOC1 | Colloidal organic carbon |
Difference in Pt HTCO determined DOC between 0.4 µm and 104 Dalton filtered samples | |
Micromoles/litre | |
CORGCOD1 | Dissolved organic carbon |
High temperature Pt catalytic oxidation (GF/F filtered) | |
Micromoles/litre | |
CORGCOD2 | Dissolved organic carbon |
High temperature Pt catalytic oxidation (0.4 µm pore filtered) | |
Micromoles/litre | |
CORGCOTX | Total organic carbon |
High temperature Pt catalytic oxidation (unfiltered) | |
Micromoles/litre | |
SDOCCOD1 | Dissolved organic carbon standard deviation |
High temperature Pt catalytic oxidation (GF/F filtered) | |
Micromoles/litre | |
SEOCCOD1 | Dissolved organic carbon standard error |
High temperature Pt catalytic oxidation (GF/F filtered) | |
Micromoles/litre | |
SEOCCOTX | Total organic carbon standard error |
High temperature Pt catalytic oxidation (unfiltered) | |
Micromoles/litre |
Data Originator
Dr Chou Lei, ULB, Brussels, Belgium.
Sampling strategy and methodology
Water samples were collected using either 10 l acid-cleaned polypropylene bottles deployed manually or Niskin/GoFlo bottles deployed on a CTD rosette.
Water bottle samples were filtered using pre-ashed (450 °C) GF/F filters. 10 ml samples were transferred into 15 ml glass ampoules which were poisoned with 100 µl of 1 g/l HgCl2 and sealed.
Back at the laboratory the samples were assayed using a Shimadzu TOC-5000 analyser.
Comments on data quality
Belgica BG9309
The ULB data set contains a number of high values of up to nearly 6000 µM. Of particular concern are the data from the upper 300m from station 11 which jump from 138 µM at 400m to 2403 µM at 300m and some of the data from the Zodiac transects. The IBM data from station 11 (but a different cast) give values of 1-200 µM in the upper 200m and their values for most samples from the rias are significantly lower than the ULB data.
The ULB values from the upper 300m of station 11 have been flagged suspect, together with samples from the rias in excess of 400 µM. The possibility of contamination of some samples has been suggested by the data originator as the cause of the problem. Values in the range 200-400 µM have been left unflagged but users should bear in mind that they may also be contaminated to some extent.
References
Cauwet, G. 1994. HTCO method for dissolved organic carbon analysis in seawater: influence of catalyst on blank estimation, Marine Chemistry, 47, 55 64.
Miller, A.E.J, Mantoura, R.F.C., Preston, M.R. and Suzuki, Y, 1993. Preliminary study of DOC in the Tamar Estuary, UK, using UV-persulphate and HTCO techniques. Mar. Chem., 41, 223-228.
Project Information
No Project Information held for the Series
Data Activity or Cruise Information
Data Activity
Start Date (yyyy-mm-dd) | 1993-05-05 |
End Date (yyyy-mm-dd) | 1993-05-05 |
Organization Undertaking Activity | Free University of Brussels, Laboratory of Chemical Oceanography and Water Geochemistry |
Country of Organization | Belgium |
Originator's Data Activity Identifier | BG9309_CTD_GC24 |
Platform Category | lowered unmanned submersible |
BODC Sample Metadata Report for BG9309_CTD_GC24
Sample reference number | Nominal collection volume(l) | Bottle rosette position | Bottle firing sequence number | Minimum pressure sampled (dbar) | Maximum pressure sampled (dbar) | Depth of sampling point (m) | Bottle type | Sample quality flag | Bottle reference | Comments |
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551970 | 10.00 | 1.20 | 2.70 | 1.50 | Niskin bottle | No problem reported | ||||
551971 | 10.00 | 9.30 | 10.80 | 9.60 | General Oceanics GO-FLO water sampler | No problem reported |
Please note:the supplied parameters may not have been sampled from all the bottle firings described in the table above. Cross-match the Sample Reference Number above against the SAMPRFNM value in the data file to identify the relevant metadata.
Related Data Activity activities are detailed in Appendix 1
Cruise
Cruise Name | BG9309 |
Departure Date | 1993-04-19 |
Arrival Date | 1993-05-06 |
Principal Scientist(s) | Roland Wollast (Free University of Brussels, Laboratory of Chemical Oceanography and Water Geochemistry) |
Ship | RV Belgica |
Complete Cruise Metadata Report is available here
Fixed Station Information
No Fixed Station Information held for the Series
BODC Quality Control Flags
The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:
Flag | Description |
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Blank | Unqualified |
< | Below detection limit |
> | In excess of quoted value |
A | Taxonomic flag for affinis (aff.) |
B | Beginning of CTD Down/Up Cast |
C | Taxonomic flag for confer (cf.) |
D | Thermometric depth |
E | End of CTD Down/Up Cast |
G | Non-taxonomic biological characteristic uncertainty |
H | Extrapolated value |
I | Taxonomic flag for single species (sp.) |
K | Improbable value - unknown quality control source |
L | Improbable value - originator's quality control |
M | Improbable value - BODC quality control |
N | Null value |
O | Improbable value - user quality control |
P | Trace/calm |
Q | Indeterminate |
R | Replacement value |
S | Estimated value |
T | Interpolated value |
U | Uncalibrated |
W | Control value |
X | Excessive difference |
SeaDataNet Quality Control Flags
The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:
Flag | Description |
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0 | no quality control |
1 | good value |
2 | probably good value |
3 | probably bad value |
4 | bad value |
5 | changed value |
6 | value below detection |
7 | value in excess |
8 | interpolated value |
9 | missing value |
A | value phenomenon uncertain |
B | nominal value |
Q | value below limit of quantification |
Appendix 1: BG9309_CTD_GC24
Related series for this Data Activity are presented in the table below. Further information can be found by following the appropriate links.
If you are interested in these series, please be aware we offer a multiple file download service. Should your credentials be insufficient for automatic download, the service also offers a referral to our Enquiries Officer who may be able to negotiate access.
Series Identifier | Data Category | Start date/time | Start position | Cruise |
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1263535 | Water sample data | 1993-05-05 09:16:00 | 50.27993 N, 0.00279 E | RV Belgica BG9309 |
1662745 | Water sample data | 1993-05-05 09:16:00 | 50.27993 N, 0.00279 E | RV Belgica BG9309 |