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Metadata Report for BODC Series Reference Number 1879520

Metadata Summary

Data Description

Data Category Water sample data
Instrument Type
Niskin bottle  discrete water samplers
SIS Dissolved Oxygen Analyser  titrators
Instrument Mounting lowered unmanned submersible
Originating Country United Kingdom
Originator Dr Penny Holliday
Originating Organization National Oceanography Centre, Southampton
Processing Status banked
Online delivery of data Download available - Ocean Data View (ODV) format
Project(s) NOCS National Capability

Data Identifiers

Originator's Identifier DY031_CTD_DOXY_213:DY031_084
BODC Series Reference 1879520

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 2015-06-15 17:51
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval -

Spatial Co-ordinates

Latitude 56.68332 N ( 56° 41.0' N )
Longitude 6.28337 W ( 6° 17.0' W )
Positional Uncertainty 0.05 to 0.1 n.miles
Minimum Sensor or Sampling Depth 4.7 m
Maximum Sensor or Sampling Depth 29.6 m
Minimum Sensor or Sampling Height 6.4 m
Maximum Sensor or Sampling Height 31.3 m
Sea Floor Depth 36.0 m
Sea Floor Depth Source SCILOG
Sensor or Sampling Distribution Unspecified -
Sensor or Sampling Depth Datum Unspecified -
Sea Floor Depth Datum Unspecified -


BODC CODERankUnitsTitle
ADEPZZ011MetresDepth (spatial coordinate) relative to water surface in the water body
BOTTFLAG1Not applicableSampling process quality flag (BODC C22)
DOKGWITX1Micromoles per kilogramConcentration of oxygen {O2 CAS 7782-44-7} per unit mass of the water body [dissolved plus reactive particulate phase] by Winkler titration
DOXYWITX1Micromoles per litreConcentration of oxygen {O2 CAS 7782-44-7} per unit volume of the water body [dissolved plus reactive particulate phase] by Winkler titration
FIRSEQID1DimensionlessBottle firing sequence number
OXYTMP011Degrees CelsiusTemperature of oxygen fixation
ROSPOSID1DimensionlessBottle rosette position identifier
SAMPRFNM1DimensionlessSample reference number

Definition of BOTTFLAG

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 supplied by Natural Environment Research Council (NERC)

You must always use the following attribution statement to acknowledge the source of the information: "Contains data supplied by Natural Environment Research Council."

Narrative Documents

SIS Instruments Dissolved Oxygen Analyser

The SIS Instruments Dissolved Oxygen Analyser (DOA) is a PC controlled instrument which is used for the determination of dissolved oxygen in aqueous solutions by the Winkler (1888) titration method. The system consists of a transportable box containing a Metrohm 765 Dosimat motor burette, alternating light photometer and an interface box which provides, via an RS 232 serial link, communication between computer and the instruments. The box also contains a stand with a stirrer used to hold the sample flask. The titration endpoint is determined by eye. Alongside the DOA, SIS instruments provide Windows database and processing software, which is required for data storage and post-processing of the acquired data.


Dimensions 43 x 54 x 41 cm
Weight 20 kg
Voltage 120 and 240 V AC
Frequency 50 to 60 Hz
Burette Metrohm 765 Dosimat
Photometer Alternating light photometer operating with two wavelengths, 15 Bit ADC
Accuracy Absolute 0.3 %
Repeated 0.1%

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.


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.

Discrete Oxygen Samples from CTD bottles for RRS Discovery Cruise DY031

Originator's Protocol for Data Acquisition and Analysis

Water samples were drawn from the CTD rosette bottles deployed during the cruise with samples taken from 80 of the total of 85 CTD casts undertaken.

Dissolved oxygen (DO) concentrations were measured in discrete seawater samples collected during DY031. Sampling and analysis were performed 24 hours a day using Winkler photometric auto-titration following 'Go-Ships' protocols (Langdon, 2010) based on the standard methodologies of Carpenter,1965 adapted for large scale hydrographic studies (e.g. Culberson, 1991 and Dickson, 1995). For more information see the cruise report.


Carpenter, J.H. 1965. The Chesapeake Bay Institute technique for the Winkler dissolved oxygen method. Limnol.and Oceanogr. 10:141-143.

Culberson, C.H. 1991. Dissolved Oxgyen. WHPO Publication 91-1.

Dickson, A.D. 1995. Determination of dissolved oxygen in sea water by Winkler titration. WOCE Operations Manual, Part 3.1.3 Operations and Methods, WHP Office Report WHPO 91-1.

Langdon. C. 2010. Determination of dissolved oxygen in seawater by Winkler titration using the amperometric technique. The GO-SHIP Repeat hydrography manual: A collection of expert reports and guidelines. IOCCP report No.14.

BODC Data Processing Procedures

The sample data were supplied to BODC in MStar format. Data received were loaded into the BODC database using established BODC data banking procedure. Originator's parameters were mapped with BODC codes as follows;

Originator's Parameter Unit Description BODC Parameter code BODC Unit Comments
botoxy µmol/kg Concentration of oxygen {O2 CAS 7782-44-7} per unit mass of the water body [dissolved plus reactive particulate phase] by Winkler titration DOKGWITX µmol/kg n/a
botoxy_per_l µM Concentration of oxygen {O2 CAS 7782-44-7} per unit volume of the water body [dissolved plus reactive particulate phase] by Winkler titration DOXYWITX µM n/a
botoxytemp °C Temperature of oxygen fixation OXYTMP01 °C n/a

Project Information

NOCS National Capability

The National Oceanography Centre Southampton National Capability focuses on long term science concerned with basin/decadal variability of the Ocean.

Data Activity or Cruise Information

Data Activity

Start Date (yyyy-mm-dd) 2015-06-15
End Date (yyyy-mm-dd) 2015-06-15
Organization Undertaking ActivityNational Oceanography Centre, Southampton
Country of OrganizationUnited Kingdom
Originator's Data Activity IdentifierDY031_CTD_DY031_084
Platform Categorylowered unmanned submersible

No Document Information Held for the Series


Cruise Name DY031
Departure Date 2015-05-29
Arrival Date 2015-06-17
Principal Scientist(s)N Penny Holliday (National Oceanography Centre, Southampton)
Ship RRS Discovery

Complete Cruise Metadata Report is available here

Fixed Station Information

Fixed Station Information

Station NameEllett Line/Extended Ellett Line Station 2G
CategoryOffshore location
Latitude56° 40.98' N
Longitude6° 16.98' W
Water depth below MSL40.0 m

Ellett Line/Extended Ellett Line: Station 2G

Station 2G is one of the fixed CTD stations, which together form The Extended Ellett Line. The line lies between Iceland and the Sound of Mull (Scotland) crossing the Iceland Basin and Rockall Trough via the outcrop of Rockall. As part of this initiative, CTD dips, together with associated discrete sampling of the water column, have typically been carried out annually at this station since September 1996.

Prior to September 1996, Station 2G was part of a shorter repeated survey section, consisting of 35 fixed stations, known as The Ellett Line (originally termed the Anton Dohrn Seamount Section). This line incorporated those stations across the Rockall Trough and Scottish shelf between Rockall and the Sound of Mull and was visited at regular intervals (usually at least once a year) between 1975 and January 1996. During this period Station 2G was also referred to as Station C2.

Related Fixed Station activities are detailed in Appendix 1

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: Ellett Line/Extended Ellett Line Station 2G

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
90625CTD or STD cast1976-04-04 18:52:0056.685 N, 6.2866 WRRS Challenger CH5A/76
91782CTD or STD cast1976-05-29 00:50:0056.685 N, 6.285 WRRS Challenger CH8/76
91118CTD or STD cast1977-03-08 08:25:0056.6766 N, 6.2833 WRRS Challenger CH4/77
94374CTD or STD cast1977-07-25 17:06:0056.6816 N, 6.2916 WRRS Challenger CH11/77
95003CTD or STD cast1978-04-20 21:38:0056.6833 N, 6.2833 WRRS Challenger CH6/78
95771CTD or STD cast1978-06-09 20:37:0056.6833 N, 6.2833 WRRS Challenger CH9/78
186234CTD or STD cast1978-08-11 12:23:0056.6833 N, 6.2833 WRRS Challenger CH11B/78
190939CTD or STD cast1978-09-14 14:52:0056.6833 N, 6.285 WRRS Challenger CH11D/78
314281CTD or STD cast1978-11-04 16:10:0056.6933 N, 6.2933 WRRS Challenger CH14B/78
95783CTD or STD cast1979-09-13 08:05:0056.685 N, 6.28 WRRS Challenger CH13/79
187839CTD or STD cast1980-03-04 23:50:0056.6833 N, 6.2833 WRRS Challenger CH4/80
189625CTD or STD cast1980-06-01 00:03:0056.6816 N, 6.2816 WRRS Challenger CH9B/80
186848CTD or STD cast1980-10-02 09:00:0056.6833 N, 6.285 WRRS Challenger CH15/80
312502CTD or STD cast1981-01-27 15:38:0056.6833 N, 6.2833 WRRS Challenger CH2/81
188020CTD or STD cast1981-04-14 06:06:0056.6866 N, 6.2916 WRRS Challenger CH6A/81
191390CTD or STD cast1981-07-07 06:01:0056.68 N, 6.2816 WRRS Challenger CH10/81
187329CTD or STD cast1981-10-19 21:53:0056.6883 N, 6.295 WRRS Challenger CH15/81
312747CTD or STD cast1982-01-27 15:06:0056.6817 N, 6.2833 WRRS Challenger CH2/82
189047CTD or STD cast1982-04-26 04:02:0056.6783 N, 6.2833 WRRS Challenger CH7A/82
189059CTD or STD cast1982-04-26 05:33:0056.6816 N, 6.2883 WRRS Challenger CH7A/82
187378CTD or STD cast1983-02-09 18:40:0056.6833 N, 6.2833 WRRS Challenger CH3/83
193292CTD or STD cast1983-05-23 20:30:0056.685 N, 6.2833 WRRS Challenger CH7B/83
96762CTD or STD cast1983-08-15 01:52:0056.6816 N, 6.295 WRRS Challenger CH11/83
313093CTD or STD cast1984-06-26 17:55:0056.6833 N, 6.29 WRRS Challenger CH2/84
257821CTD or STD cast1984-11-25 11:05:0056.6816 N, 6.2816 WRRS Challenger CH10/84
258559CTD or STD cast1985-01-28 13:38:0056.6816 N, 6.2833 WRRS Challenger CH1/85
253764CTD or STD cast1985-05-07 22:14:0056.6833 N, 6.2833 WRRS Challenger CH4/85
261070CTD or STD cast1985-08-19 01:25:0056.6833 N, 6.2833 WRRS Challenger CH8/85
255795CTD or STD cast1985-12-15 18:00:0056.685 N, 6.2783 WRRS Frederick Russell FR13/85
345894CTD or STD cast1986-06-12 05:50:0056.6833 N, 6.2833 WMV Dawn Sky DSK1/86
346664CTD or STD cast1986-08-27 22:31:0056.6833 N, 6.2833 WRRS Frederick Russell FR7B/86
348032CTD or STD cast1986-09-26 21:03:0056.6883 N, 6.28 WRRS Frederick Russell FR8/86
348068CTD or STD cast1986-09-27 10:46:0056.6833 N, 6.2833 WRRS Frederick Russell FR8/86
264055CTD or STD cast1987-01-08 21:42:0056.6833 N, 6.2833 WRRS Challenger CH9
384186CTD or STD cast1987-03-27 13:15:0056.6833 N, 6.2833 WRRS Frederick Russell FR13/87
250686CTD or STD cast1987-05-01 03:53:0056.685 N, 6.2783 WRRS Challenger CH14
343537CTD or STD cast1987-06-29 02:14:0056.6833 N, 6.2833 WRRS Frederick Russell FR14B/87
256018CTD or STD cast1987-09-01 00:34:0056.6833 N, 6.2833 WRRS Frederick Russell FR18/87
251315CTD or STD cast1987-11-24 17:10:0056.6833 N, 6.2833 WRRS Challenger CH22
267041CTD or STD cast1988-03-07 05:46:0056.6866 N, 6.2733 WRRS Challenger CH25
262663CTD or STD cast1988-06-08 10:59:0056.6933 N, 6.2766 WRRS Challenger CH30
265231CTD or STD cast1989-01-23 16:48:0056.7 N, 6.3 WRRS Discovery D180
265741CTD or STD cast1989-05-05 13:51:0056.6833 N, 6.2833 WRV Lough Foyle LF1/89
317518CTD or STD cast1989-08-04 17:48:0056.685 N, 6.28 WRV Lough Foyle LF2/89
316632CTD or STD cast1989-11-25 04:56:0056.6833 N, 6.2833 WRRS Charles Darwin CD44
314729CTD or STD cast1990-03-12 20:57:0056.6833 N, 6.27 WRRS Challenger CH63_2
315179CTD or STD cast1990-06-29 02:24:0056.6833 N, 6.2833 WRRS Challenger CH67A
259956CTD or STD cast1990-09-03 08:08:0056.6833 N, 6.2833 WRRS Challenger CH71A
315930CTD or STD cast1990-12-10 05:39:0056.6833 N, 6.285 WRRS Challenger CH74A_1
382364CTD or STD cast1991-02-24 09:54:0056.685 N, 6.2817 WRRS Challenger CH75B
316078CTD or STD cast1991-07-01 21:32:0056.6867 N, 6.2833 WRRS Challenger CH81
384230CTD or STD cast1991-11-26 15:21:0056.685 N, 6.2883 WRRS Challenger CH86B
384997CTD or STD cast1992-03-07 22:10:0056.68 N, 6.2817 WRRS Challenger CH89B
386377CTD or STD cast1992-09-25 23:37:0056.6833 N, 6.295 WRRS Challenger CH97
385270CTD or STD cast1993-03-14 00:05:0056.6783 N, 6.2667 WRRS Challenger CH101B
386052CTD or STD cast1993-05-20 20:28:0056.68 N, 6.2733 WRRS Challenger CH103
388009CTD or STD cast1993-09-10 06:16:0056.6833 N, 6.2833 WRRS Challenger CH105
388962CTD or STD cast1994-03-14 18:51:0056.6833 N, 6.2833 WRRS Challenger CH110
389615CTD or STD cast1994-05-08 23:57:0056.6833 N, 6.2833 WRRS Challenger CH112
390689CTD or STD cast1994-08-15 20:19:0056.6833 N, 6.2833 WRRS Challenger CH114
391853CTD or STD cast1994-11-21 19:51:0056.6833 N, 6.2817 WRRS Challenger CH116
434584CTD or STD cast1995-04-14 15:07:0056.6833 N, 6.2753 WRRS Charles Darwin CD92B
390296CTD or STD cast1995-07-29 15:49:0056.6867 N, 6.288 WRRS Challenger CH120
433901CTD or STD cast1996-01-11 15:07:0056.6833 N, 6.2833 WRRS Challenger CH124
1289199Water sample data1996-01-11 15:07:0056.6833 N, 6.2833 WRRS Challenger CH124
1074900CTD or STD cast2000-01-31 19:46:0056.67983 N, 6.28633 WRRS Discovery D245
845224CTD or STD cast2003-07-25 14:34:0056.68525 N, 6.28592 WFS Poseidon PO300_2
666945CTD or STD cast2004-07-12 11:22:0056.68533 N, 6.28033 WFS Poseidon PO314
897055CTD or STD cast2005-10-26 08:08:0056.68452 N, 6.28146 WRRS Charles Darwin CD176
776953CTD or STD cast2006-10-30 05:06:4156.68333 N, 6.28167 WRRS Discovery D312
954818CTD or STD cast2009-06-25 04:32:4956.68533 N, 6.28447 WRRS Discovery D340A
1052990CTD or STD cast2010-05-21 18:26:3356.68433 N, 6.28733 WRRS Discovery D351
1897041Water sample data2010-05-21 18:32:0056.68414 N, 6.28762 WRRS Discovery D351
1195272CTD or STD cast2011-05-20 03:20:1556.68783 N, 6.2825 WRRS Discovery D365
1203218CTD or STD cast2012-08-02 09:50:0056.68138 N, 6.28405 WRRS Discovery D379
1220603CTD or STD cast2013-05-23 14:02:0056.6841 N, 6.2843 WRRS James Cook JC086
1371432CTD or STD cast2014-07-17 13:36:5156.6831 N, 6.2832 WRRS James Clark Ross JR20140531 (JR302)
1723618CTD or STD cast2015-06-15 17:46:4856.6833 N, 6.2834 WRRS Discovery DY031
1764870CTD or STD cast2016-06-20 07:24:3656.6833 N, 6.2822 WRRS Discovery DY052
1766004Currents -subsurface Eulerian2016-06-20 07:24:5956.68328 N, 6.28218 WRRS Discovery DY052
1875174Water sample data2016-06-20 07:28:0056.68328 N, 6.28217 WRRS Discovery DY052
1975777CTD or STD cast2017-05-14 10:03:4156.6831 N, 6.2827 WRRS Discovery DY078 (DY079)