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Metadata Report for BODC Series Reference Number 344577


Metadata Summary

Data Description

Data Category CTD or STD cast
Instrument Type
NameCategories
Bissett-Bermann 9040 CTD system  CTD; water temperature sensor; salinity sensor
Instrument Mounting research vessel
Originating Country United Kingdom
Originator -
Originating Organization Scottish Marine Biological Association (now Scottish Association for Marine Science)
Processing Status banked
Online delivery of data Download available - Ocean Data View (ODV) format
Project(s) -
 

Data Identifiers

Originator's Identifier CH9/87/113
BODC Series Reference 344577
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 1987-01-21 23:16
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval -
 

Spatial Co-ordinates

Latitude 55.65000 N ( 55° 39.0' N )
Longitude 5.43000 W ( 5° 25.8' W )
Positional Uncertainty Unspecified
Minimum Sensor or Sampling Depth 1.68 m
Maximum Sensor or Sampling Depth 131.26 m
Minimum Sensor or Sampling Height 5.74 m
Maximum Sensor or Sampling Height 135.32 m
Sea Floor Depth 137.0 m
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 Instantaneous - Depth measured below water line or instantaneous water body surface
 

Parameters

BODC CODERankUnitsTitle
PRESPR011DecibarsPressure (spatial coordinate) exerted by the water body by profiling pressure sensor and correction to read zero at sea level
PSALPR011DimensionlessPractical salinity of the water body by conductivity cell and computation using UNESCO 1983 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

The pressure channel for some casts from the cruise include negative values.

The affected values have been flagged, but their presence casts doubt on the pressure calibration.


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

Bissett-Bermann 9040 Conductivity Temperature and Depth

The basic configuration of the B-B 9040 CTD incorporates pressure, temperature and conductivity sensors which could be logged digitally. This system also made it possible to derive other parameters, such as salinity, depth and sound velocity.

The instrument was versatile and it was possible to attach a dissolved oxygen sensor or to change the CTD housing, allowing it to obtain data from deeper layers in the water column. The accuracy for salinity is ±0.02 ppt , and ±0.02°C for temperature.

This instrument was also known as the Plessey 9040.

RRS Challenger Cruise 9/87 CTD Data Documentation

Introduction

Documentation for the CTD data collected on RRS Challenger Cruise 9/87 (January 1987) by the Scottish Marine Biological Association, Oban, Argyll, Scotland, UK, under the direction of D. J. Ellett.

Caution

Inspection of the pressure records from this cruise reveals several negative values (by up to 9db) at the start of some records, (while the temperature and salinity values appear reasonable), thus casting some doubt on the accuracy of the pressure calibration. These data values have been flagged.

Instrumentation

The instrument used was a Bissett Berman 9040 CTD system and the data were logged on a Hewlett Packard 9820 and stored in an integer format. Instrument lowering and raising speeds were between 0.5m/s and 1m/s. An acoustic pinger was placed above the CTD to give an accurate depth measurement, this could then be used to check the CTD pressure calibration. An NIO bottle with reversing thermometers was placed above the pinger, within 2m of the CTD system. A bottle sample was taken at the bottom of the cast providing the temperature and salinity are uniform at that point. If large temperature or salinity gradients were present then the bottle sample was triggered at a suitable site on the upcast. A surface salinity sample was also taken at the start of the dip.

Calibration

The CTD was not calibrated in the laboratory. The manufacturer's calibration was used and water samples taken to check the calibration and apply corrections where necessary.

Temperature

The manufacturer's calibration was used to convert the raw data to to physical units using the equation below:

Temperature (°C) = (10**6/Pt -2238.68/55.84)

where Pt is the temperature period in microseconds

These values were then plotted against the water bottle (i.e. reversing thermometer) temperatures and a regression line fitted to the data such that:

Temperature(WB) = m x Temperature(CTD) + c

Then the regression coefficients (m and c) were applied to correct the CTD temperature data - these are given in the table below.

Conductivity

The manufacturer's calibration was used to convert the raw data to to physical units using the equation below:

Conductivity (mmho/cm) = (106/Pc - 4995)/58.12 + 10

where Pc is the conductivity period in microseconds

The water bottle salinities and corrected CTD temperatures were used to calculate the water bottle conductivity values. These values were then plotted against the CTD conductivities and a regression line fitted to the data such that:

Conductivity(WB) = m x Conductivity(CTD) + c

Then the regression coefficients were applied to correct the CTD conductivity data - these are given in the table below.

Pressure

The depths from the acoustic pinger were noted where the bottle samples were taken and then used to check the calibration of the pressure sensor - unless calibration values were available from the reversing thermometers. The equation below was used to convert the pressure period to physical units.

Pressure = (106/Pd - 9712)/0.26267

where Pd is the pressure period in microseconds

A regression fit was carried out using the calibration values and the slope and intercept determined. The pressure values could then be corrected using:

Pressure (CORR) = m x Pressure(CTD) + c

The fit of the CTD data to the water bottle calibration data is given in the table below:

Variable Slope (m) Intercept (c)
Temperature (°C) 1.0029623 -0.002745
Conductivity (mmho/cm) 1.0031466 -0.088331
Pressure (dbar) 0.9980069 1.850888

Data Processing

Obvious wild points were edited out of the calibration file and the calibration programs run to obtain values for the slopes and intercepts for temperature, pressure and conductivity. These were then applied to the uncalibrated data. Conductivities were converted to conductivity ratios and then converted to salinities using UNESCO recommended routines and sigma-t was calculated. The data values were then sieved to ensure a minimum separation between pressure values of 1 dbar. The data were then visually inspected and major spikes flagged.

References

Fofonoff, N.P. and Millard Jr., R.C. (1983).
Algorithms for the computation of fundamental properties of sea water. UNESCO Technical Paper on Marine Science 44.


Project Information


No Project Information held for the Series

Data Activity or Cruise Information

Cruise

Cruise Name CH9
Departure Date 1987-01-08
Arrival Date 1987-01-22
Principal Scientist(s)Anton Edwards (Scottish Marine Biological Association)
Ship RRS Challenger

Complete Cruise Metadata Report is available here


Fixed Station Information

Fixed Station Information

Station NameDML Clyde Stations
CategoryOffshore area
Latitude55° 32.50' N
Longitude5° 12.50' W
Water depth below MSL

DML Clyde Stations

The Clyde Stations are a group of survey stations circling the Isle of Arran in the Firth of Clyde (Scotland). The group comprises 14 fixed CTD stations, which were established as part of routine monitoring work on the Scottish continental shelf by Dunstaffnage Marine Laboratory (DML). The Clyde Stations were occupied during the 1980s and 1990s.

Map of standard DML Clyde CTD Stations

BODC image

Map produced using the GEBCO Digital Atlas.

The white triangles indicate the nominal positions of each standard DML Clyde Station.

Nominal station details

DML Clyde Stations: Firth of Clyde

Station Nominal latitude Nominal longitude Approx.
depth (m)
Comment
CL1 55° 17.0' N 05° 17.0' W 44 Great Plateau
CL2 55° 21.0' N 05° 22.0' W 45  
CL3 55° 26.0' N 05° 26.0' W 30  
CL4 55° 31.0' N 05° 26.0' W 72  
CL5 55° 35.0' N 05° 25.0' W 115 Off Carradale
CL6 55° 39.0' N 05° 26.0' W 150  
CL7 55° 43.0' N 05° 19.5' W 120  
CL8 55° 48.0' N 05° 15.0' W 150 West of Inchmarnock
CL9 55° 44.0' N 05° 11.0' W 150  
CL10 55° 40.0' N 05° 04.0' W 162  
CL11 55° 36.0' N 04° 59.0' W 130  
CL12 55° 31.0' N 04° 59.5' W 110 Off Holy Island
CL13 55° 26.0' N 05° 02.0' W 124  
CL14 55° 21.0' N 05° 04.0' W 52  

Related Fixed Station activities are detailed in Appendix 1

Fixed Station Information

Station NameDML Clyde Station CL6
CategoryOffshore location
Latitude55° 39.00' N
Longitude5° 26.00' W
Water depth below MSL150.0 m

DML Clyde Station CL6

DML Clyde Station CL6 is one of 14 fixed CTD stations circling the Isle of Arran in the Firth of Clyde, Scotland. The station was established by scientists at Dunstaffnage Marine Laboratory (DML).

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
Q value below limit of quantification

Appendix 1: DML Clyde Stations

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
257292CTD or STD cast1984-11-18 23:06:0055.4333 N, 5.0333 WRRS Challenger CH10/84
257311CTD or STD cast1984-11-19 01:57:0055.6 N, 4.9833 WRRS Challenger CH10/84
258246CTD or STD cast1984-12-06 02:19:0055.5833 N, 5.4166 WRRS Challenger CH10/84
259458CTD or STD cast1985-02-04 19:09:0055.5766 N, 5.4133 WRRS Challenger CH1/85
253125CTD or STD cast1985-05-04 02:12:0055.5783 N, 5.4116 WRRS Challenger CH4/85
260423CTD or STD cast1985-08-15 05:38:0055.5766 N, 5.41 WRRS Challenger CH8/85
262208CTD or STD cast1985-12-06 19:43:0055.575 N, 5.4083 WRRS Frederick Russell FR13/85
345126CTD or STD cast1986-06-07 03:38:0055.2667 N, 5.3 WMV Dawn Sky DSK1/86
345138CTD or STD cast1986-06-07 04:02:0055.2833 N, 5.2667 WMV Dawn Sky DSK1/86
345292CTD or STD cast1986-06-08 05:39:0055.65 N, 5.4333 WMV Dawn Sky DSK1/86
345311CTD or STD cast1986-06-08 06:27:0055.7 N, 5.35 WMV Dawn Sky DSK1/86
347667CTD or STD cast1986-09-23 17:01:0055.7 N, 5.35 WRRS Frederick Russell FR8/86
347679CTD or STD cast1986-09-23 18:33:0055.65 N, 5.4333 WRRS Frederick Russell FR8/86
382991CTD or STD cast1987-03-20 00:45:0055.65 N, 5.4317 WRRS Frederick Russell FR13/87
383226CTD or STD cast1987-03-21 11:12:0055.6 N, 4.9783 WRRS Frederick Russell FR13/87
249790CTD or STD cast1987-04-24 19:13:0055.435 N, 5.0266 WRRS Challenger CH14
249986CTD or STD cast1987-04-25 18:19:0055.6516 N, 5.435 WRRS Challenger CH14
349895CTD or STD cast1987-06-21 19:13:0055.7 N, 5.35 WRRS Frederick Russell FR14B/87
384740CTD or STD cast1991-12-01 12:17:0055.3567 N, 5.3717 WRRS Challenger CH86B
384752CTD or STD cast1991-12-01 13:08:0055.435 N, 5.4283 WRRS Challenger CH86B
384764CTD or STD cast1991-12-01 13:54:0055.5167 N, 5.4383 WRRS Challenger CH86B
384776CTD or STD cast1991-12-01 14:39:0055.585 N, 5.4183 WRRS Challenger CH86B
384788CTD or STD cast1991-12-01 15:23:0055.6567 N, 5.43 WRRS Challenger CH86B
384807CTD or STD cast1991-12-01 16:16:0055.725 N, 5.3183 WRRS Challenger CH86B
384819CTD or STD cast1991-12-01 17:05:0055.8033 N, 5.255 WRRS Challenger CH86B
384820CTD or STD cast1991-12-01 18:06:0055.73 N, 5.1833 WRRS Challenger CH86B
384832CTD or STD cast1991-12-01 19:00:0055.675 N, 5.0683 WRRS Challenger CH86B
384844CTD or STD cast1991-12-01 19:53:0055.6 N, 4.9833 WRRS Challenger CH86B
384856CTD or STD cast1991-12-01 20:46:0055.52 N, 4.99 WRRS Challenger CH86B
384868CTD or STD cast1991-12-01 21:31:0055.4417 N, 5.0333 WRRS Challenger CH86B
384881CTD or STD cast1991-12-01 22:17:0055.3583 N, 5.0733 WRRS Challenger CH86B
384900CTD or STD cast1991-12-02 00:35:0055.44 N, 5.0383 WRRS Challenger CH86B
384924CTD or STD cast1991-12-02 03:04:0055.44 N, 5.0333 WRRS Challenger CH86B
384948CTD or STD cast1991-12-02 05:32:0055.4383 N, 5.04 WRRS Challenger CH86B
387412CTD or STD cast1992-10-04 22:48:0055.35 N, 5.0667 WRRS Challenger CH97
387424CTD or STD cast1992-10-04 23:35:0055.4333 N, 5.0333 WRRS Challenger CH97
387436CTD or STD cast1992-10-05 00:31:0055.515 N, 4.9817 WRRS Challenger CH97
387448CTD or STD cast1992-10-05 01:23:0055.6017 N, 4.9833 WRRS Challenger CH97
387461CTD or STD cast1992-10-05 02:16:0055.6667 N, 5.0667 WRRS Challenger CH97
387473CTD or STD cast1992-10-05 03:10:0055.7317 N, 5.1817 WRRS Challenger CH97
387485CTD or STD cast1992-10-05 03:59:0055.7967 N, 5.2483 WRRS Challenger CH97
387497CTD or STD cast1992-10-05 04:51:0055.72 N, 5.325 WRRS Challenger CH97
387516CTD or STD cast1992-10-05 06:27:0055.585 N, 5.4183 WRRS Challenger CH97
387528CTD or STD cast1992-10-05 07:10:0055.5133 N, 5.4333 WRRS Challenger CH97
387541CTD or STD cast1992-10-05 07:54:0055.4317 N, 5.435 WRRS Challenger CH97
387553CTD or STD cast1992-10-05 08:40:0055.3517 N, 5.3667 WRRS Challenger CH97
387565CTD or STD cast1992-10-05 09:22:0055.2817 N, 5.2833 WRRS Challenger CH97
385398CTD or STD cast1993-03-17 18:30:0055.2783 N, 5.2783 WRRS Challenger CH101B
385405CTD or STD cast1993-03-17 20:21:0055.3517 N, 5.365 WRRS Challenger CH101B
385417CTD or STD cast1993-03-17 21:40:0055.4317 N, 5.44 WRRS Challenger CH101B
385429CTD or STD cast1993-03-17 22:32:0055.5167 N, 5.435 WRRS Challenger CH101B
385430CTD or STD cast1993-03-18 00:16:0055.58 N, 5.4133 WRRS Challenger CH101B
385442CTD or STD cast1993-03-18 01:09:0055.6517 N, 5.4333 WRRS Challenger CH101B
385454CTD or STD cast1993-03-18 02:52:0055.7183 N, 5.3167 WRRS Challenger CH101B
385466CTD or STD cast1993-03-18 03:58:0055.8 N, 5.25 WRRS Challenger CH101B
385478CTD or STD cast1993-03-18 05:29:0055.7367 N, 5.1783 WRRS Challenger CH101B
385491CTD or STD cast1993-03-18 06:29:0055.6633 N, 5.0683 WRRS Challenger CH101B
385509CTD or STD cast1993-03-18 08:23:0055.6 N, 5.0 WRRS Challenger CH101B
385510CTD or STD cast1993-03-18 09:11:0055.515 N, 4.985 WRRS Challenger CH101B
385522CTD or STD cast1993-03-18 10:53:0055.4267 N, 5.0483 WRRS Challenger CH101B
385534CTD or STD cast1993-03-18 11:45:0055.3483 N, 5.0667 WRRS Challenger CH101B
386107CTD or STD cast1993-05-21 21:07:0055.285 N, 5.2833 WRRS Challenger CH103
386120CTD or STD cast1993-05-21 23:16:0055.36 N, 5.0633 WRRS Challenger CH103
386297CTD or STD cast1993-05-23 05:03:0055.5733 N, 5.4233 WRRS Challenger CH103
386304CTD or STD cast1993-05-23 05:44:0055.5017 N, 5.4383 WRRS Challenger CH103
388440CTD or STD cast1993-09-15 03:09:0055.3657 N, 5.0785 WRRS Challenger CH105
388532CTD or STD cast1993-09-15 15:13:0055.7108 N, 5.332 WRRS Challenger CH105
388556CTD or STD cast1993-09-15 17:23:0055.574 N, 5.423 WRRS Challenger CH105
388568CTD or STD cast1993-09-15 18:27:0055.5027 N, 5.4418 WRRS Challenger CH105
388697CTD or STD cast1994-03-10 18:58:0055.5017 N, 5.4383 WRRS Challenger CH110
388704CTD or STD cast1994-03-10 19:44:0055.5733 N, 5.4233 WRRS Challenger CH110
388882CTD or STD cast1994-03-11 22:30:0055.3585 N, 5.072 WRRS Challenger CH110
433741CTD or STD cast1996-01-10 10:16:0055.2833 N, 5.2833 WRRS Challenger CH124
433753CTD or STD cast1996-01-10 11:22:0055.35 N, 5.3667 WRRS Challenger CH124
433765CTD or STD cast1996-01-10 12:42:0055.4333 N, 5.4333 WRRS Challenger CH124
433777CTD or STD cast1996-01-10 13:32:0055.5167 N, 5.4333 WRRS Challenger CH124
433789CTD or STD cast1996-01-10 14:22:0055.5833 N, 5.4167 WRRS Challenger CH124
433790CTD or STD cast1996-01-10 15:21:0055.65 N, 5.4333 WRRS Challenger CH124
433808CTD or STD cast1996-01-10 16:26:0055.7167 N, 5.325 WRRS Challenger CH124
433821CTD or STD cast1996-01-10 17:32:0055.8 N, 5.25 WRRS Challenger CH124
433833CTD or STD cast1996-01-10 18:28:0055.7333 N, 5.1833 WRRS Challenger CH124
433845CTD or STD cast1996-01-10 19:35:0055.6667 N, 5.0667 WRRS Challenger CH124
433857CTD or STD cast1996-01-10 20:32:0055.6 N, 4.9833 WRRS Challenger CH124
433869CTD or STD cast1996-01-10 21:39:0055.5167 N, 4.9917 WRRS Challenger CH124
433870CTD or STD cast1996-01-10 22:58:0055.4333 N, 5.0333 WRRS Challenger CH124
433882CTD or STD cast1996-01-10 23:54:0055.35 N, 5.0667 WRRS Challenger CH124

Appendix 2: DML Clyde Station CL6

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
345292CTD or STD cast1986-06-08 05:39:0055.65 N, 5.4333 WMV Dawn Sky DSK1/86
347679CTD or STD cast1986-09-23 18:33:0055.65 N, 5.4333 WRRS Frederick Russell FR8/86
382991CTD or STD cast1987-03-20 00:45:0055.65 N, 5.4317 WRRS Frederick Russell FR13/87
249986CTD or STD cast1987-04-25 18:19:0055.6516 N, 5.435 WRRS Challenger CH14
384788CTD or STD cast1991-12-01 15:23:0055.6567 N, 5.43 WRRS Challenger CH86B
385442CTD or STD cast1993-03-18 01:09:0055.6517 N, 5.4333 WRRS Challenger CH101B
433790CTD or STD cast1996-01-10 15:21:0055.65 N, 5.4333 WRRS Challenger CH124