Metadata Report for BODC Series Reference Number 411978


Metadata Summary

Data Description

Data Category CTD or STD cast
Instrument Type
NameCategories
Neil Brown Smart CTD  CTD; water temperature sensor; salinity sensor
Instrument Mounting research vessel
Originating Country United Kingdom
Originator -
Originating Organization Scottish Office Agriculture and Fisheries Department Aberdeen Marine Laboratory (now Marine Scotland Aberdeen Marine Laboratory)
Processing Status banked
Project(s) -
 

Data Identifiers

Originator's Identifier SC04/91/0108
BODC Series Reference 411978
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 1991-04-21 09:09
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval -
 

Spatial Co-ordinates

Latitude 61.16820 N ( 61° 10.1' N )
Longitude 2.60070 W ( 2° 36.0' W )
Positional Uncertainty Unspecified
Minimum Sensor Depth 2.58 m
Maximum Sensor Depth 480.31 m
Minimum Sensor Height 69.69 m
Maximum Sensor Height 547.41 m
Sea Floor Depth 550.0 m
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 Instantaneous - Depth measured below water line or instantaneous water body surface
 

Parameters

BODC CODE Rank Units Short Title Title
CNDCST01 1 Siemens per metre CTDCond Electrical conductivity of the water body by CTD
PRESPR01 1 Decibars Pres_Z Pressure (spatial co-ordinate) exerted by the water body by profiling pressure sensor and corrected to read zero at sea level
PSALST01 1 Dimensionless P_sal_CTD Practical salinity of the water body by CTD and computation using UNESCO 1983 algorithm
SIGTEQ01 1 Kilograms per cubic metre SigmaTheta Sigma-theta of the water body by computation from salinity and potential temperature using UNESCO 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

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 Smart Conductivity, Temperature and Depth profiler

The Smart CTD was developed by WHOI, Neil Brown Instrument Systems and MIT and consists of an internally recording CTD which can be programmable to accommodate various sampling schemes. The data retrieval is done via connectors to a computer, where it is digitally logged.

This instrument was designed to be used with minimal technical expertise and to be replaced if problems arise, rather than being repaired at sea.

FRV Scotia 0491S CTD Data Documentation

Introduction

Documentation for data collected on FRV Scotia cruise 0491S CTD (15 April 1991 - 24 April 1991) by Fisheries Research Services, Aberdeen, UK.

Instrumentation

The temperature and salinity data were collected using a Neil Brown Instrument Systems (NBIS) CTD instrument which was calibrated using bottle samples and thermometer readings to produce the following equations:

T(cal) = T(obs)

C(cal) = C(obs)

For further information contact:

George Slesser/Bill Turrell
FRS, Marine Laboratory
PO Box 101
Victoria Road
Aberdeen AB11 9DB
G.Slesser@marlab.ac.uk or b.turrell@marlab.ac.uk

General Data Screening carried out by BODC

BODC screen both the series header qualifying information and the parameter values in the data cycles themselves.

Header information is inspected for:

Documents are written by BODC highlighting irregularities which cannot be resolved.

Data cycles are inspected using time or depth series plots of all parameters. Currents are additionally inspected using vector scatter plots and time series plots of North and East velocity components. These presentations undergo intrinsic and extrinsic screening to detect infeasible values within the data cycles themselves and inconsistencies as seen when comparing characteristics of adjacent data sets displaced with respect to depth, position or time. Values suspected of being of non-oceanographic origin may be tagged with the BODC flag denoting suspect value; the data values will not be altered.

The following types of irregularity, each relying on visual detection in the plot, are amongst those which may be flagged as suspect:

If a large percentage of the data is affected by irregularities then a Problem Report will be written rather than flagging the individual suspect values. Problem Reports are also used to highlight irregularities seen in the graphical data presentations.

Inconsistencies between the characteristics of the data set and those of its neighbours are sought and, where necessary, documented. This covers inconsistencies such as the following:

This intrinsic and extrinsic screening of the parameter values seeks to confirm the qualifying information and the source laboratory's comments on the series. In screening and collating information, every care is taken to ensure that errors of BODC making are not introduced.


Project Information


No Project Information held for the Series

Data Activity or Cruise Information

Cruise

Cruise Name 0491S
Departure Date 1991-04-15
Arrival Date 1991-04-24
Principal Scientist(s)Bill Turrell (Scottish Office Agriculture and Fisheries Department Aberdeen Marine Laboratory)
Ship FRV Scotia

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