Search the data

Metadata Report for BODC Series Reference Number 2113455


Metadata Summary

Data Description

Data Category Water sample data
Instrument Type
NameCategories
Niskin bottle  discrete water samplers
Instrument Mounting lowered unmanned submersible
Originating Country United Kingdom
Originator Dr Peter Brown
Originating Organization University of East Anglia School of Environmental Sciences
Processing Status banked
Online delivery of data Download available - Ocean Data View (ODV) format
Project(s) ANDREX
 

Data Identifiers

Originator's Identifier JC030_CTD_STAB_3270:CTD02
BODC Series Reference 2113455
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 2008-12-31 20:49
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval -
 

Spatial Co-ordinates

Latitude 53.49997 S ( 53° 30.0' S )
Longitude 30.00001 E ( 30° 0.0' E )
Positional Uncertainty 0.05 to 0.1 n.miles
Minimum Sensor or Sampling Depth 6.2 m
Maximum Sensor or Sampling Depth 5169.3 m
Minimum Sensor or Sampling Height 350.7 m
Maximum Sensor or Sampling Height 5513.8 m
Sea Floor Depth 5520.0 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)
D18OMXWT1Parts per thousandEnrichment of oxygen-18 in water molecules {18O in H2O CAS 14797-71-8} {delta(18)O} in the water body by mass spectrometry
FIRSEQID1DimensionlessBottle firing sequence number
ROSPOSID1DimensionlessBottle rosette position identifier
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

Open 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.

If the Information Provider does not provide a specific attribution statement, or if you are using Information from several Information Providers and multiple attributions are not practical in your product or application, you may consider using the following:

"Contains public sector information licensed under the Open Government Licence v1.0."


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.

Stable oxygen isotope (O18) measurements from CTD bottle samples collected during ANDREX cruise JC030

Originator's Protocol for Data Acquisition and Analysis

Water samples for the determination of stable oxygen isotope (O18) were drawn from 20 litre Niskin bottles from a 24-rosette sampling system mounted on a Sea-Bird 9/11 plus CTD. Out of the 27 CTD stations carried out during the cruise, every other station was sampled for O18(14 stations in total) as part of the ANDREX-fresh project funded via a NERC Small Grant ('Freshwater Export from the Weddell Gyre: Magnitude, Variability and Impacts'). Due to the limited amount of samples which could be analysed, most samples were drawn from near surface bottles.

Samples were drawn into 50 ml glass bottles which had been rinsed once with water from the bottle sample. A silicon bung was inserted and a metal crimp overlaid, which was sealed with a pair of crimping tongs. The bung and crimp were the same as those used for sealing bottles of OSIL standard seawater. It was realised that too many samples were taken near the start of the section, and so the 50 ml glass bottles would run out before the end. Therefore, the standard seawater bottles that had been left over from the salinity analyses were used. All samples were transported to the UK and delivered to the NERC Isotope Geosciences Laboratory, Keyworth, for laboratory analysis.

The analysis procedure used the equilibration method for oxygen, following Epstein and Mayeda (1953), and a VG Isoprep 18 and Sira 10 mass spectrometer. Random duplicates were run to assess data integrity and an average precision better than ±0.02 ppt was obtained.

References Cited

Epstein, S. and Mayeda, T., 1953. Variation of O18 content of waters from natural sources, Geochemica et Cosmochemica Acta, 4, 213.

BODC Data Processing Procedures

All data were received in one ASCII formatted file. Data received were loaded into the BODC database using established BODC data banking procedures. One discrepancy was found between the data originator's metadata and the Sea-Bird .btl files and log sheets. The rosette position numbers 22 and 23 provided for CTD cast 27 were the wrong way round in comparison to the pressure values therefore these were swapped without referral with the data originator. In addition, the following changes were made; all WOCE quality control flags provided by the originator were converted into BODC standard flags, 2 (good) = no flag, 3 (questionable) = 'L', and all absent data values were removed. The data were screened in-house prior to loading. Data were then loaded without any further changes. The following table shows how the variables were mapped to appropriate BODC parameter codes:

Originator's Parameter Unit Description BODC Parameter Code BODC Unit Comments
EXPOCODE - Cruise identifier - - -
SECT_ID - Cruise code - - -
STNNBR - CTD station number - - -
BTLNBR - Rosette position - - -
DATE - Date - - -
TIME - Time - - -
LATITUDE Degrees Latitude - - -
LONGITUDE Degrees Longitude - - -
PRESSURE dbar Pressure - - -
DELO18 Parts per thousand Stable oxygen isotope (O18) D18OMXWT Parts per thousand -
DELO18_FLAG - Stable oxygen isotope (O18) flags - - -

Data Quality Report

None (BODC assessment).

Problem Report

None (BODC assessment).


Project Information

Antarctic Deep Water Rates of Export (ANDREX) project document

ANDREX is a UK field programme aimed at investigating the role of the Weddell Gyre in the Meridional Overturning Circulation (MOC) and its influence on deep ocean properties.

The MOC is a critical regulator of Earth's climate and is crucial for deep water ventilation across the globe. Surface currents transport waters towards the poles, where they become dense and sink, flowing equatorward as deep, cool currents. The MOC ensures that the deep oceans remain ventilated and conducive to life, and is also important for anthropogenic carbon sequestration. The southern closure of the MOC in the Weddell Sea is strongly influenced by the Weddell Gyre, which facilitates the exchange of waters between the Antarctic Circumpolar Current (ACC) and the waters of the continental shelf. Cooling and sea ice formation in the Weddell Sea lead to overturning of the water column and the ventilation of Antarctic Bottom Water (AABW), which flows out of the Weddell Sea and into the deep oceans to the north. Thus, the Weddell Gyre plays an important role in the properties of deep ocean waters on a global scale.

The goals of ANDREX are to investigate the exchange of water masses between the ACC and the Weddell Sea, including AABW formation and ventilation rates, carbon and nutrient cycling, the influence of fresh water input from sea ice, precipitation and glacial melt, and the role of the Weddell Gyre in anthropogenic carbon sequestration. The project includes hydrographic, ventilation tracer, biogeochemical and bathymetric measurements along the outer rim of the Weddell Gyre.

ANDREX is funded by the UK Natural Environment Research Council (NERC) Antarctic Funding Initiative (AFI) and involves scientists from the National Oceanography Centre, Southampton (NOC), the British Antarctic Survey (BAS), the University of East Anglia (UEA), the University of Manchester, the Alfred Wegener Institut (AWI) and the Woods Hole Oceanographic Institution (WHOI).

For more information please see the official project website at ANDREX


Data Activity or Cruise Information

Data Activity

Start Date (yyyy-mm-dd) 2008-12-31
End Date (yyyy-mm-dd) 2008-12-31
Organization Undertaking ActivityNational Oceanography Centre, Southampton
Country of OrganizationUnited Kingdom
Originator's Data Activity IdentifierJC030_CTD_CTD02
Platform Categorylowered unmanned submersible

BODC Sample Metadata Report for JC030_CTD_CTD02

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
233523   20.00 1 1 5279.80 5280.20 5169.30 Niskin bottle No problem reported    
233524   20.00 2 2 5230.00 5230.60 5121.40 Niskin bottle No problem reported    
233525   20.00 3 3 5169.70 5171.10 5063.20 Niskin bottle No problem reported    
233526   20.00 4 4 5104.90 5106.10 5000.40 Niskin bottle No problem reported    
233527   20.00 5 5 4585.50 4586.20 4496.70 Niskin bottle No problem reported    
233528   20.00 6 6 4070.50 4071.20 3996.50 Niskin bottle No problem reported    
233529   20.00 7 7 3556.10 3557.30 3495.80 Niskin bottle Bottle leak   Bottle leaked
233530   20.00 8 8 3044.20 3045.00 2996.00 Niskin bottle No problem reported    
233531   20.00 9 9 2534.40 2535.20 2497.30 Niskin bottle No problem reported    
233532   20.00 10 10 2023.80 2024.90 1996.90 Niskin bottle No problem reported    
233533   20.00 11 11 1513.70 1514.20 1495.00 Niskin bottle No problem reported    
233534   20.00 12 12 1097.00 1099.20 1085.40 Niskin bottle No problem reported    
233535   20.00 13 13 1009.30 1010.10  998.40 Niskin bottle No problem reported    
233536   20.00 14 14  806.80  809.30  799.50 Niskin bottle Bottle leak   Bottle leaked
233537   20.00 15 15  606.10  607.20  600.60 Niskin bottle No problem reported    
233538   20.00 16 16  403.30  403.80  399.50 Niskin bottle No problem reported    
233539   20.00 17 17  304.50  305.80  302.40 Niskin bottle No problem reported    
233540   20.00 18 18  203.40  204.50  202.10 Niskin bottle No problem reported    
233541   20.00 19 19  152.00  153.50  151.20 Niskin bottle No problem reported    
233542   20.00 20 20  103.00  103.40  102.20 Niskin bottle No problem reported    
233543   20.00 21 21   76.00   76.40   75.40 Niskin bottle No problem reported    
233544   20.00 22 22   51.70   52.20   51.40 Niskin bottle No problem reported    
233545   20.00 23 23   27.10   27.80   27.10 Niskin bottle Bottle leak   Bottle leaked
233546   20.00 24 24    6.20    6.30    6.20 Niskin bottle 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 JC030
Departure Date 2008-12-26
Arrival Date 2009-01-30
Principal Scientist(s)Sheldon Bacon (National Oceanography Centre, Southampton)
Ship RRS James Cook

Complete Cruise Metadata Report is available here


Fixed Station Information

Fixed Station Information

Station NameWOCE Hydrographic Section IOS6
CategoryOffshore route/traverse

World Ocean Circulation Experiment (WOCE) Indian One Time Survey Hydrographic Section 6 South (I06S)

WOCE established a hydrographic section between south Africa and Antarctica and designated it I06S. The section is located within the geographic boundaries of -31.0000, 24.9335 (North-Western corner) and -69.04733, 30.11000 (South-Eastern corner).

There are two I06S designated cruises which are presented below with the addition of any other cruises which have occupied this line and links to the relevant cruise narratives or cruise reports.

Cruise Country Ship Start Date End Date Comments
MD74 (CIVA1) France Marion Dufresne 23/01/1993 09/03/1993 Indian One Time Survey
MD103 (CIVA2) France Marion Dufresne 01/02/1996 31/03/1996 Indian One Time Survey
Knox22RR United States of America RV Roger Revelle 12/11/2008 02/01/2009 Repeat
JC030 United Kingdom RRS James Cook 26/12/2008 31/01/2009 Part of cruise track occupies the line

Related Fixed Station activities are detailed in Appendix 2


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
B nominal value
Q value below limit of quantification

Appendix 1: JC030_CTD_CTD02

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
1253123Water sample data2008-12-31 20:49:0053.49997 S, 30.00001 ERRS James Cook JC030

Appendix 2: WOCE Hydrographic Section IOS6

Related series for this Fixed Station 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
1102158CTD or STD cast2008-12-31 18:30:0453.5 S, 30.0 ERRS James Cook JC030
1253123Water sample data2008-12-31 20:49:0053.49997 S, 30.00001 ERRS James Cook JC030
1102263CTD or STD cast2009-01-01 05:59:5354.0 S, 30.0001 ERRS James Cook JC030
1253135Water sample data2009-01-01 08:16:0054.00002 S, 30.00007 ERRS James Cook JC030
1102275CTD or STD cast2009-01-01 14:31:1054.4999 S, 30.0001 ERRS James Cook JC030
2113467Water sample data2009-01-01 17:00:5654.49993 S, 30.00009 ERRS James Cook JC030
1253147Water sample data2009-01-01 17:01:0054.49993 S, 30.00009 ERRS James Cook JC030