Metadata Report for BODC Series Reference Number 1004662


Metadata Summary

Data Description

Data Category CTD or STD cast
Instrument Type
NameCategories
Neil Brown MK3 CTD  CTD; water temperature sensor; salinity sensor; dissolved gas sensors
Instrument Mounting research vessel
Originating Country United Kingdom
Originator Dr Peter Saunders
Originating Organization Institute of Oceanographic Sciences Deacon Laboratory (now National Oceanography Centre, Southampton)
Processing Status banked
Online delivery of data Download available - Ocean Data View (ODV) format
Project(s) WOCE
UK WOCE
 

Data Identifiers

Originator's Identifier CTD12335
BODC Series Reference 1004662
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 1993-01-29 13:03
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval 2.0 decibars
 

Spatial Co-ordinates

Latitude 31.96050 S ( 31° 57.6' S )
Longitude 12.36750 E ( 12° 22.1' E )
Positional Uncertainty 0.0 to 0.01 n.miles
Minimum Sensor or Sampling Depth 0.99 m
Maximum Sensor or Sampling Depth 3988.67 m
Minimum Sensor or Sampling Height -
Maximum Sensor or Sampling Height -
Sea Floor Depth -
Sea Floor Depth Source -
Sensor or Sampling Distribution Variable common depth - All sensors are grouped effectively at the same depth, but this depth varies significantly during the series
Sensor or Sampling Depth Datum Instantaneous - Depth measured below water line or instantaneous water body surface
Sea Floor Depth Datum -
 

Parameters

BODC CODERankUnitsTitle
DOXYPR011Micromoles per litreConcentration of oxygen {O2 CAS 7782-44-7} per unit volume of the water body [dissolved plus reactive particulate phase] by in-situ Beckmann probe
OXYSBB011PercentSaturation of oxygen {O2 CAS 7782-44-7} in the water body [dissolved plus reactive particulate phase] by in-situ Beckmann probe and computation from concentration using Benson and Krause algorithm
POTMCV011Degrees CelsiusPotential temperature of the water body by computation using UNESCO 1983 algorithm
PRESPR011DecibarsPressure (spatial co-ordinate) exerted by the water body by profiling pressure sensor and corrected to read zero at sea level
PSALST011DimensionlessPractical salinity of the water body by CTD and computation using UNESCO 1983 algorithm
SIGTPR011Kilograms per cubic metreSigma-theta of the water body by CTD and computation from salinity and potential temperature using UNESCO algorithm
TEMPST011Degrees CelsiusTemperature of the water body by CTD or STD

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

Neil Brown MK3 CTD

The Neil Brown MK3 conductivity-temperature-depth (CTD) profiler consists of an integral unit containing pressure, temperature and conductivity sensors with an optional dissolved oxygen sensor in a pressure-hardened casing. The most widely used variant in the 1980s and 1990s was the MK3B. An upgrade to this, the MK3C, was developed to meet the requirements of the WOCE project.

The MK3C includes a low hysteresis, titanium strain gauge pressure transducer. The transducer temperature is measured separately, allowing correction for the effects of temperature on pressure measurements. The MK3C conductivity cell features a free flow, internal field design that eliminates ducted pumping and is not affected by external metallic objects such as guard cages and external sensors.

Additional optional sensors include pH and a pressure-temperature fluorometer. The instrument is no longer in production, but is supported (repair and calibration) by General Oceanics.

Specifications

These specification apply to the MK3C version.

Pressure Temperature Conductivity
Range

6500 m

3200 m (optional)

-3 to 32°C 1 to 6.5 S cm-1
Accuracy

0.0015% FS

0.03% FS < 1 msec

0.0005°C

0.003°C < 30 msec

0.0001 S cm-1

0.0003 S cm-1 < 30 msec

Further details can be found in the specification sheet.

RRS Discovery 199 CTD Data Documentation

Introduction

CTD profile data are presented from the WOCE A11 cruise Discovery 199 as reported by Saunders et al. (1993).

Instrumentation and Methodology

Instrumentation Summary

The CTD profiles were taken with a Neil Brown Systems MkIIIb CTD (Deep01) mounted beneath a bottle rosette. The CTD was fitted with a pressure sensor, conductivity cell, platinum resistance thermometer, a SensorMedic dissolved oxygen sensor, a Sea Tech Inc. 100cm path transmissometer s/n 35, a Simrad altimeter model 807-200m and an IOSDL 10 kHz pinger. No fluorometer was attached to the CTD.

Data Acquisition

Lowering rates for the CTD package were generally in the range 0.5-1.0ms-1 but could be up to 1.5ms-1. CTD data were logged at 16 frames per second. The CTD deck unit passes raw data to a dedicated Level A microcomputer where 1 second averages are assembled. During this process the Level A calculates the rate of change of temperature and a median sorting routine detects and removes pressure spikes. These data are sent to the Level B for archival. The data are then passed to a Level C workstation for conversion to Pstar format and calibration.

A total of 91 stations were occupied (12247 - 12337).

Data Processing

The 1 second data passed to the Level C were converted to Pstar format and initially calibrated with coefficients from laboratory calibrations followed by a number of calibration corrections. The up cast data were extracted for merging with the bottle firing codes, on time, thus the CTD variables were reconciled with the bottle samples. Final calibrations were applied using the sample bottle data. Finally, down cast data were extracted, sorted on pressure and averaged to 2db values, with any gaps filled by linear interpolation.

The data were worked up to WOCE standards by the data originators before being supplied to BODC.

BODC Data Processing

No further calibrations were applied to the data received by BODC. BODC were mainly concerned with the screening and banking of the data.

The CTD data were received as 2db averaged pressure sorted down cast data. Parameters were pressure (dbar), temperature (°C), salinity (psu), and oxygen (µmol/kg). No transmissometer data were received.

The data were converted into the BODC internal format (PXF) to allow the use of in-house software tools, notably the graphics editor. The oxygen data were converted from µmol/kg to µmol/l.

Spikes in the data were manually flagged 'suspect' by modification of the associated quality control flag. In this way none of the original data values were edited or deleted during quality control. Spikiness was seen in some oxygen profiles at depth and these were flagged suspect. The temperature and salinity profiles for 258-263 exhibited many large instabilities and these have been flagged suspect. For profile 320 the T+S is fairly constant between 80-530db.

Once screened, the CTD data were loaded into a database under the Oracle relational database management system. The start time stored in the database is the CTD deployment time, and the end time is the time the CTD was removed from the water. Actually these times are more precisely the start and end of data logging. Latitude and longitude are the mean positions between the start and end times calculated from the master navigation in the binary merged file.

References

Saunders, P.M. et al. (1993). RRS Discovery Cruise 199. Institute of Oceanographic Sciences Deacon Laboratory, Cruise Report No. 234, 69pp.


Project Information

World Ocean Circulation Experiment (WOCE)

The World Ocean Circulation Experiment (WOCE) was a major international experiment which made measurements and undertook modelling studies of the deep oceans in order to provide a much improved understanding of the role of ocean circulation in changing and ameliorating the Earth's climate.

WOCE had two major goals:


UK WOCE

The UK made a substantial contribution to the international World Ocean Circulation Experiment (WOCE) project by focusing on two important regions:

  1. Southern Ocean - links all the worlds oceans, controlling global climate.
  2. North Atlantic - directly affects the climate of Europe.

A major part of the UK effort was in the Southern Ocean and work included:

In the North Atlantic the UK undertook:

Satellite ocean surface topography, temperature and wind data were merged with in situ observations and models to create a complete description of ocean circulation, eddy motion and the way the ocean is driven by the atmosphere.

The surveys were forerunners to the international Global Ocean Observing System (GOOS). GOOS was later established to monitor annual to decadal changes in ocean circulation and heat storage which are vital in the prediction of climate change.


Data Activity or Cruise Information

Cruise

Cruise Name D199
Departure Date 1992-12-22
Arrival Date 1993-02-01
Principal Scientist(s)Peter M Saunders (Institute of Oceanographic Sciences Deacon Laboratory)
Ship RRS Discovery

Complete Cruise Metadata Report is available here


Fixed Station Information

Fixed Station Information

Station NameWOCE Hydrographic Programme Section A11
CategoryOffshore route/traverse

WOCE Hydrographic Programme Section A11

This section is part of the One-Time Survey of World Ocean Circulation Experiment (WOCE) designated A11. A hydrographic section from Chile to South Africa was covered and a full suite of physical, chemical, biological, meteorological and tracer measurements were made.

This section was covered by Discovery cruise D199 and took place from 22 December 1992 to 1 February 1993. The map below shows the geographical coverage of section A11.

BODC image

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
Q value below limit of quantification

Appendix 1: WOCE Hydrographic Programme Section A11

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
1003695CTD or STD cast1992-12-27 23:00:0044.98167 S, 60.00483 WRRS Discovery D199
1003702CTD or STD cast1992-12-28 01:43:0044.9945 S, 59.939 WRRS Discovery D199
1003714CTD or STD cast1992-12-28 04:24:0044.984 S, 59.78417 WRRS Discovery D199
1003726CTD or STD cast1992-12-28 09:36:0044.97967 S, 59.1195 WRRS Discovery D199
1003738CTD or STD cast1992-12-28 14:29:0044.9905 S, 58.54733 WRRS Discovery D199
1003751CTD or STD cast1992-12-28 17:39:0044.988 S, 58.4165 WRRS Discovery D199
1003763CTD or STD cast1992-12-28 21:12:0044.99817 S, 58.36167 WRRS Discovery D199
1003775CTD or STD cast1992-12-29 02:16:0044.99383 S, 57.82083 WRRS Discovery D199
1003787CTD or STD cast1992-12-29 09:15:0045.01083 S, 57.41083 WRRS Discovery D199
1003799CTD or STD cast1992-12-29 15:09:0045.01817 S, 56.998 WRRS Discovery D199
1003806CTD or STD cast1992-12-29 22:09:0045.02283 S, 56.49917 WRRS Discovery D199
1003818CTD or STD cast1992-12-30 08:17:0045.02417 S, 55.75083 WRRS Discovery D199
1003831CTD or STD cast1992-12-30 16:59:0044.98417 S, 54.78633 WRRS Discovery D199
1003843CTD or STD cast1992-12-31 03:23:0045.02 S, 53.8355 WRRS Discovery D199
1003855CTD or STD cast1992-12-31 15:29:0044.9395 S, 52.81567 WRRS Discovery D199
1003867CTD or STD cast1993-01-01 01:08:0045.03467 S, 51.74267 WRRS Discovery D199
1003879CTD or STD cast1993-01-02 19:19:0045.041 S, 50.7495 WRRS Discovery D199
1003880CTD or STD cast1993-01-03 03:24:0045.02283 S, 49.75367 WRRS Discovery D199
1003892CTD or STD cast1993-01-03 11:08:0045.00583 S, 48.76717 WRRS Discovery D199
1003911CTD or STD cast1993-01-03 18:57:0044.9985 S, 47.76267 WRRS Discovery D199
1003923CTD or STD cast1993-01-04 02:48:0045.00883 S, 46.75183 WRRS Discovery D199
1003935CTD or STD cast1993-01-04 10:27:0045.00383 S, 45.75367 WRRS Discovery D199
1003947CTD or STD cast1993-01-04 17:50:0044.98967 S, 44.7375 WRRS Discovery D199
1003959CTD or STD cast1993-01-05 01:10:0044.9985 S, 43.75217 WRRS Discovery D199
1003960CTD or STD cast1993-01-05 08:55:0044.99833 S, 42.75367 WRRS Discovery D199
1003972CTD or STD cast1993-01-05 18:08:0044.9905 S, 41.754 WRRS Discovery D199
1003984CTD or STD cast1993-01-06 05:41:0044.99833 S, 40.75283 WRRS Discovery D199
1003996CTD or STD cast1993-01-06 14:27:0044.983 S, 39.76567 WRRS Discovery D199
1004011CTD or STD cast1993-01-06 22:29:0044.98167 S, 38.731 WRRS Discovery D199
1004023CTD or STD cast1993-01-07 06:12:0045.01017 S, 37.71617 WRRS Discovery D199
1004035CTD or STD cast1993-01-07 14:19:0044.986 S, 36.7485 WRRS Discovery D199
1004047CTD or STD cast1993-01-08 00:27:0044.99167 S, 35.75117 WRRS Discovery D199
1004059CTD or STD cast1993-01-08 08:24:0044.997 S, 34.76183 WRRS Discovery D199
1004060CTD or STD cast1993-01-08 15:57:0044.99067 S, 33.77317 WRRS Discovery D199
1004072CTD or STD cast1993-01-09 01:15:0045.01367 S, 32.77283 WRRS Discovery D199
1004084CTD or STD cast1993-01-09 08:50:0045.001 S, 31.72033 WRRS Discovery D199
1004096CTD or STD cast1993-01-09 16:49:0044.99 S, 30.75683 WRRS Discovery D199
1004103CTD or STD cast1993-01-10 01:40:0045.0 S, 29.77317 WRRS Discovery D199
1004115CTD or STD cast1993-01-10 12:09:0044.9965 S, 28.73967 WRRS Discovery D199
1004127CTD or STD cast1993-01-10 20:48:0045.00733 S, 27.76967 WRRS Discovery D199
1004139CTD or STD cast1993-01-11 04:20:0045.006 S, 26.73467 WRRS Discovery D199
1004140CTD or STD cast1993-01-11 11:33:0044.99417 S, 25.735 WRRS Discovery D199
1004152CTD or STD cast1993-01-11 19:04:0045.01967 S, 24.74883 WRRS Discovery D199
1004164CTD or STD cast1993-01-12 02:01:0044.98617 S, 23.72633 WRRS Discovery D199
1004176CTD or STD cast1993-01-12 08:48:0044.99567 S, 22.75883 WRRS Discovery D199
1004188CTD or STD cast1993-01-12 16:08:0045.013 S, 21.73567 WRRS Discovery D199
1004207CTD or STD cast1993-01-13 00:28:0044.994 S, 20.71817 WRRS Discovery D199
1004219CTD or STD cast1993-01-15 04:25:0044.98983 S, 19.74633 WRRS Discovery D199
1004220CTD or STD cast1993-01-15 13:38:0045.01267 S, 18.57367 WRRS Discovery D199
1004232CTD or STD cast1993-01-15 21:06:0044.99983 S, 17.39833 WRRS Discovery D199
1004244CTD or STD cast1993-01-16 04:19:0044.99083 S, 16.2225 WRRS Discovery D199
1004256CTD or STD cast1993-01-16 11:45:0045.00567 S, 15.00783 WRRS Discovery D199
1004268CTD or STD cast1993-01-16 18:24:0044.5435 S, 14.00417 WRRS Discovery D199
1004281CTD or STD cast1993-01-17 01:33:0044.11233 S, 13.0095 WRRS Discovery D199
1004293CTD or STD cast1993-01-17 08:23:0043.66683 S, 12.02117 WRRS Discovery D199
1004300CTD or STD cast1993-01-17 15:18:0043.23283 S, 11.04633 WRRS Discovery D199
1004312CTD or STD cast1993-01-17 22:33:0042.81833 S, 10.0895 WRRS Discovery D199
1004324CTD or STD cast1993-01-18 05:47:0042.371 S, 9.091 WRRS Discovery D199
1004336CTD or STD cast1993-01-18 13:02:0041.93133 S, 8.16783 WRRS Discovery D199
1004348CTD or STD cast1993-01-18 20:23:0041.52333 S, 7.20333 WRRS Discovery D199
1004361CTD or STD cast1993-01-19 03:11:0041.1535 S, 6.403 WRRS Discovery D199
1004373CTD or STD cast1993-01-19 12:18:0040.70717 S, 5.44317 WRRS Discovery D199
1004385CTD or STD cast1993-01-19 18:09:0040.42283 S, 4.829 WRRS Discovery D199
1004397CTD or STD cast1993-01-20 02:52:0040.0835 S, 4.04067 WRRS Discovery D199
1004404CTD or STD cast1993-01-20 10:30:0039.71967 S, 3.252 WRRS Discovery D199
1004416CTD or STD cast1993-01-20 17:58:0039.354 S, 2.47867 WRRS Discovery D199
1004428CTD or STD cast1993-01-21 01:07:0038.97067 S, 1.69133 WRRS Discovery D199
1004441CTD or STD cast1993-01-21 08:14:0038.606 S, 0.94233 WRRS Discovery D199
1004453CTD or STD cast1993-01-21 15:39:0038.24633 S, 0.162 WRRS Discovery D199
1004465CTD or STD cast1993-01-22 00:13:0037.88183 S, 0.59067 ERRS Discovery D199
1004477CTD or STD cast1993-01-22 07:33:0037.5225 S, 1.34883 ERRS Discovery D199
1004489CTD or STD cast1993-01-22 14:35:0037.15067 S, 2.10383 ERRS Discovery D199
1004490CTD or STD cast1993-01-22 21:46:0036.79033 S, 2.85833 ERRS Discovery D199
1004508CTD or STD cast1993-01-23 06:23:0036.27517 S, 3.92817 ERRS Discovery D199
1004521CTD or STD cast1993-01-23 15:22:0035.7495 S, 4.9985 ERRS Discovery D199
1004533CTD or STD cast1993-01-23 23:57:0035.213 S, 6.03433 ERRS Discovery D199
1004545CTD or STD cast1993-01-24 09:15:0034.7045 S, 7.07017 ERRS Discovery D199
1004557CTD or STD cast1993-01-24 17:51:0034.15317 S, 8.11817 ERRS Discovery D199
1004569CTD or STD cast1993-01-25 03:01:0033.67833 S, 9.14083 ERRS Discovery D199
1004570CTD or STD cast1993-01-25 15:47:0033.09283 S, 10.14917 ERRS Discovery D199
1004582CTD or STD cast1993-01-28 05:33:0030.22633 S, 15.61883 ERRS Discovery D199
1004594CTD or STD cast1993-01-28 08:49:0030.47083 S, 15.13517 ERRS Discovery D199
1004601CTD or STD cast1993-01-28 11:01:0030.57033 S, 14.98 ERRS Discovery D199
1004613CTD or STD cast1993-01-28 13:25:0030.671 S, 14.78867 ERRS Discovery D199
1004625CTD or STD cast1993-01-28 16:12:0030.75533 S, 14.643 ERRS Discovery D199
1004637CTD or STD cast1993-01-28 19:48:0030.89067 S, 14.36767 ERRS Discovery D199
1004649CTD or STD cast1993-01-29 00:46:0031.23533 S, 13.74983 ERRS Discovery D199
1004650CTD or STD cast1993-01-29 06:11:0031.54183 S, 13.16233 ERRS Discovery D199
1004674CTD or STD cast1993-01-29 19:55:0032.32033 S, 11.6425 ERRS Discovery D199
1004686CTD or STD cast1993-01-30 03:30:0032.70517 S, 10.89733 ERRS Discovery D199