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Metadata Report for BODC Series Reference Number 1868313


Metadata Summary

Data Description

Data Category Water sample data
Instrument Type
NameCategories
General Oceanics GO-FLO water sampler  discrete water samplers
Instrument Mounting lowered unmanned submersible
Originating Country France
Originator Mr Jean Marie Martin
Originating Organization École Normale Supérieure Institute of Marine Biogeochemistry
Processing Status banked
Online delivery of data Download available - Ocean Data View (ODV) format
Project(s) -
 

Data Identifiers

Originator's Identifier BG9309_CTD_DCDN_49:GC11D
BODC Series Reference 1868313
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 1993-04-30 17:28
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval -
 

Spatial Co-ordinates

Latitude 42.15960 N ( 42° 9.6' N )
Longitude 9.49005 W ( 9° 29.4' W )
Positional Uncertainty 0.05 to 0.1 n.miles
Minimum Sensor or Sampling Depth 136.7 m
Maximum Sensor or Sampling Depth 200.5 m
Minimum Sensor or Sampling Height 999.5 m
Maximum Sensor or Sampling Height 1063.3 m
Sea Floor Depth 1200.0 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)
CORGCOD21Micromoles per litreConcentration of organic carbon {organic_C CAS 7440-44-0} {DOC} per unit volume of the water body [dissolved plus reactive particulate <0.4/0.45um phase] by filtration and high temperature Pt catalytic oxidation
SAMPRFNM1DimensionlessSample reference number

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

GO-FLO Bottle

A water sampling bottle featuring close-open-close operation. The bottle opens automatically at approximately 10 metres and flushes until closed. Sampling with these bottles avoids contamination at the surface, internal spring contamination, loss of sample on deck and exchange of water from different depths.

There are several sizes available, from 1.7 to 100 litres and are made of PVC with a depth rating of up to 500 m. These bottles can be attached to a rosette or placed on a cable at selected positions.

Dissolved and Colloidal Organic Carbon for cruise Belgica BG9309

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 Jean-Marie Martin, Institut de Biogeochimie, France.

Sampling strategy and methodology

Water samples were collected using either 10 l acid-cleaned polypropylene bottles deployed manually or Teflon lined GoFlo bottles deployed on a CTD rosette. The samples were filtered under nitrogen pressure through acid-cleaned 0.4 micron Nuclepore filters. 1-2 litres were passed through the filter and discarded to guard against adsorption and/or release of organic carbon from the filter.

A 50ml sample was poisoned with HgCl2 for DOC analysis. Filtered water was then passed through a cross-flow ultra-filtration (CFF) system with a polysulphate membrane (104Daltons) to separate colloids from the truly dissolved fraction. Quadruplate samples were collected when the concentration factor was around 4-6. All filtration was conducted using ultra-clean techniques under laminar-flow clean benches.

DOC was determined on the filtrate and ultra-filtrate by high temperature catalytic oxidation using a Shimadzu TOC-5000 analyser. Samples were injected into a furnace at 680 °C onto a catalyst made of 1.2% Pt coated SiO2. The CO2 produced was measured by a non-dispersive infra-red (NDIR) detector. The instrument and water blanks were evaluated for each set of sample analysis as described by Cauwet (1994).

Comments on data quality

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) 1993-04-30
End Date (yyyy-mm-dd) 1993-04-30
Organization Undertaking ActivityFree University of Brussels, Laboratory of Chemical Oceanography and Water Geochemistry
Country of OrganizationBelgium
Originator's Data Activity IdentifierBG9309_CTD_GC11D
Platform Categorylowered unmanned submersible

BODC Sample Metadata Report for BG9309_CTD_GC11D

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
551838   10.00      137.50  139.00  136.70 General Oceanics GO-FLO water sampler No problem reported    
551839   10.00      201.80  203.30  200.50 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.

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