Metadata Report for BODC Series Reference Number 544739


Metadata Summary

Data Description

Data Category CTD or STD cast
Instrument Type
NameCategories
Plessey 9400 CTD  CTD; water temperature sensor; salinity sensor
Instrument Mounting research vessel
Originating Country United Kingdom
Originator -
Originating Organization Institute of Oceanographic Sciences Bidston Laboratory (now National Oceanography Centre, Liverpool)
Processing Status banked
Project(s) -
 

Data Identifiers

Originator's Identifier JM13/79/198
BODC Series Reference 544739
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 1979-08-29 03:20
End Time (yyyy-mm-dd hh:mm) 1979-08-29 03:21
Nominal Cycle Interval -
 

Spatial Co-ordinates

Latitude 54.16570 N ( 54° 9.9' N )
Longitude 8.00100 E ( 8° 0.1' E )
Positional Uncertainty Unspecified
Minimum Sensor Depth 5.2 m
Maximum Sensor Depth 21.3 m
Minimum Sensor Height -
Maximum Sensor Height -
Sea Floor Depth -
Sensor Distribution Variable common depth - All sensors are grouped effectively at the same depth, but this depth varies significantly during the series
Sensor Depth Datum Instantaneous - Depth measured below water line or instantaneous water body surface
Sea Floor Depth Datum -
 

Parameters

BODC CODE Rank Units Short Title Title
DEPHPR01 1 Metres CmpDep Depth below surface of the water body by profiling pressure sensor and converted to seawater depth using UNESCO algorithm
PSALPR01 1 Dimensionless P_sal Practical salinity of the water body by conductivity cell and computation using UNESCO 1983 algorithm
TEMPST01 1 Degrees Celsius WC_temp_CTD Temperature 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

Salinity noise up to 0.01 PSU.

Negative pressures down to -3db occur.

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

Plessey 9400 Conductivity, Temperature and Depth

The Plessey 9400 comprises a Plessey 6500 inductive conductivity sensor, a Plessey 4500 platinum resistance temperature sensor and a Plessey 4600 bonded strain pressure sensor.

RRS John Murray 13/79 CTD Data Documentation

Introduction

Documentation for the CTD data collected on RRS John Murray Cruise 13/79 (15 October - 6 September 1979) by the Institute of Oceanographic Sciences, Bidston (now POL).

Port of Departure Plymouth
Port of Return Barry
Area North Sea

This cruise was a contribution to the international MARSEN (Maritime Remote Sensing Experiment in the North Sea) project.

Caution

Some of the salinity data collected on this cruise are noisy (±0.01 psu)

Data Processing

The raw data were previously manually edited, resequenced and archived in 2 files. 0ne file contained temperature, salinity and depth frequencies with time elapsed and the other contained decca positional infomation.

This data set was reprocessed in Febuary 2001.

Calibrations

The following constants (obtained from printouts of the data) were used to convert to real units and calibrate.

Temperature Constant 2127.4
Salinity Constant 4997.0
Depth Constant 9718.0

The downcasts had a temperature correction applied to lessen salinity spiking.

REALT = TC(2) + ((TC(3)-TC(1))/2.0) * TIC

where:

TC(1-3) = Three successive readings of temperature (in °C)
TIC = Timing constant of the instrument = 0.35


Project Information


No Project Information held for the Series

Data Activity or Cruise Information

Cruise

Cruise Name JM13/79
Departure Date 1979-08-20
Arrival Date 1979-09-06
Principal Scientist(s)Ian D James (Institute of Oceanographic Sciences Bidston Laboratory)
Ship RRS John Murray

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