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Metadata Report for BODC Series Reference Number 1868429


Metadata Summary

Data Description

Data Category Water sample data
Instrument Type
NameCategories
Niskin bottle  discrete water samplers
Instrument Mounting lowered unmanned submersible
Originating Country Belgium
Originator Prof Lei Lei
Originating Organization Free University of Brussels, Laboratory of Chemical Oceanography and Water Geochemistry
Processing Status banked
Online delivery of data Download available - Ocean Data View (ODV) format
Project(s) -
 

Data Identifiers

Originator's Identifier BG9309_CTD_DCDN_14:GC21
BODC Series Reference 1868429
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 1993-05-04 20:18
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval -
 

Spatial Co-ordinates

Latitude 49.76950 N ( 49° 46.2' N )
Longitude 3.00272 W ( 3° 0.2' W )
Positional Uncertainty 0.05 to 0.1 n.miles
Minimum Sensor or Sampling Depth 2.6 m
Maximum Sensor or Sampling Depth 2.6 m
Minimum Sensor or Sampling Height 70.2 m
Maximum Sensor or Sampling Height 70.2 m
Sea Floor Depth 72.8 m
Sea Floor Depth Source PEVENT
Sensor or Sampling Distribution Unspecified -
Sensor or Sampling Depth Datum Unspecified -
Sea Floor Depth Datum Unspecified -
 

Parameters

BODC CODERankUnitsTitle
ADEPZZ011MetresDepth (spatial coordinate) relative to water surface in the water body
BOTTFLAG1Not applicableSampling process quality flag (BODC C22)
CORGCOD11Micromoles per litreConcentration of organic carbon {organic_C CAS 7440-44-0} {DOC} per unit volume of the water body [dissolved plus reactive particulate
SAMPRFNM1DimensionlessSample reference number
SDOCCOD11Micromoles per litreConcentration standard deviation of organic carbon {organic_C CAS 7440-44-0} {DOC} per unit volume of the water body [dissolved plus reactive particulate

Definition of BOTTFLAG

BOTTFLAGDefinition
0The sampling event occurred without any incident being reported to BODC.
1The filter in an in-situ sampling pump physically ruptured during sample resulting in an unquantifiable loss of sampled material.
2Analytical 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.
3The 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.
4During 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.
5Water was reported to be escaping from the bottle as the rosette was being recovered.
6The bottle seals were observed to be incorrectly seated and the bottle was only part full of water on recovery.
7Either 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).
8There is reason to doubt the accuracy of the sampling depth associated with the sample.
9The bottle air vent had not been closed prior to deployment giving rise to a risk of sample contamination through leakage.

Definition of Rank

  • Rank 1 is a one-dimensional parameter
  • Rank 2 is a two-dimensional parameter
  • Rank 0 is a one-dimensional parameter describing the second dimension of a two-dimensional parameter (e.g. bin depths for moored ADCP data)

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 have a capacity between 1.7 and 30 L, while Lever Action bottles have a capacity between 1.7 and 12 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) 1993-05-04
End Date (yyyy-mm-dd) 1993-05-04
Organization Undertaking ActivityFree University of Brussels, Laboratory of Chemical Oceanography and Water Geochemistry
Country of OrganizationBelgium
Originator's Data Activity IdentifierBG9309_CTD_GC21
Platform Categorylowered unmanned submersible

BODC Sample Metadata Report for BG9309_CTD_GC21

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
551964   10.00        2.30    3.80    2.60 Niskin bottle No problem reported    
551965   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
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
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
Q value below limit of quantification

Appendix 1: BG9309_CTD_GC21

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 IdentifierData CategoryStart date/timeStart positionCruise
1263492Water sample data1993-05-04 20:18:0049.7695 N, 3.00272 WRV Belgica BG9309
1662708Water sample data1993-05-04 20:18:0049.7695 N, 3.00272 WRV Belgica BG9309