Metadata Report for BODC Series Reference Number 621625


Metadata Summary

Data Description

Data Category CTD or STD cast
Instrument Type
NameCategories
SeaTech transmissometer  transmissometers
Sea-Bird SBE 19 SEACAT CTD  CTD; water temperature sensor; salinity sensor
SeaTech S131 fluorometer  fluorometers
Instrument Mounting research vessel
Originating Country United Kingdom
Originator Dr Bill Turrell
Originating Organization Fisheries Research Services Aberdeen Marine Laboratory (now Marine Scotland Aberdeen Marine Laboratory)
Processing Status banked
Project(s) -
 

Data Identifiers

Originator's Identifier SC18/02/604
BODC Series Reference 621625
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 2002-12-08 11:29
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval 1.0 decibars
 

Spatial Co-ordinates

Latitude 59.28230 N ( 59° 16.9' N )
Longitude 1.92700 W ( 1° 55.6' W )
Positional Uncertainty Unspecified
Minimum Sensor Depth 0.99 m
Maximum Sensor Depth 86.17 m
Minimum Sensor Height 12.82 m
Maximum Sensor Height 98.01 m
Sea Floor Depth 99.0 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
ATTNZR01 1 per metre Atten_red Attenuation (red light wavelength) per unit length of the water body by transmissometer
CNDCST01 1 Siemens per metre CTDCond Electrical conductivity of the water body by CTD
CPHLPR01 1 Milligrams per cubic metre chl-a_water_ISfluor Concentration of chlorophyll-a {chl-a CAS 479-61-8} per unit volume of the water body [particulate >unknown phase] by in-situ chlorophyll fluorometer
FVLTWS01 1 Volts WsVolt Instrument output (voltage) by linear-response chlorophyll fluorometer
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

Sea-Bird SBE 19 and SBE 19plus SEACAT Profiler CTDs

The SBE 19 SEACAT Profiler is a self-contained, battery powered, pumped CTD system designed to measure conductivity, temperature, and pressure in marine or fresh water environments to depths of 10,500 meters. It was replaced by the SBE 19 plus model in 2001. An updated version of this instrument is the SBE 19 plus V2, which incorporates an electronics upgrade and additional features, with six differentially amplified A/D input channels, one RS-232 data input channel, and 64 MB FLASH memory.

The standard CTD unit comes with a plastic housing (rated to 600 m), although this can be replaced by titanium housing for depths up to 7000 m. It is typically used for CTD profiling although a conversion kit is available for mooring deployments. The CTD can also be attached to an SBE 36 CTD Deck Unit and Power/Data Interface Module (PDIM) for real-time operation on single-core armored cable up to 10,000 m.

Specifications

Parameter SBE 19 SBE 19 plus
Temperature

Range: -5 to +35 °C

Accuracy: 0.01 °C

Resolution: 0.001 °C

Calibration: +1 to +32 °C*

Range: -5 to +35 °C

Accuracy: 0.005 °C

Resolution: 0.0001 °C

Calibration: +1 to +32 °C*

Conductivity

Range: 0 to 7 S m -1 (0 to 70 mmho cm -1 )

Accuracy: 0.001 S m -1

Resolution: 0.0001 S m -1

Calibration: 0 to 7 S m -1 . Physical calibration over the range 1.4 - 6 S m -1 *

Range: 0 to 9 Sm -1

Accuracy: 0.0005

Resolution: 0.00005 (most oceanic waters, resolves 0.4 ppm in salinity); 0.00007 (high salinity waters, resolves 0.4 ppm in salinity); 0.00001 (fresh waters, resolves 0.1 ppm in salinity)

Calibration: 0 to 9 S m -1 . Physical calibration over the range 1.4 - 6 S m -1 *

Strain gauge pressure sensor

Range: 0 to100, 150, 300, 500, 1000, 1500, 3000, 5000, 10000 or 15000 psia

Accuracy: 0.25% of full scale range (100 - 1500 psia); 0.15% of full scale range (3000 - 15000 psia)

Resolution: 0.015% of full scale

Calibration: 0 to full scale in 20% steps

Range: 0 to 20, 100, 350, 1000, 2000, 3500 or 7000 m

Accuracy: 0.1% of full scale range

Resolution: 0.002% of full scale range

Calibration: ambient pressure to full scale range in 5 steps

*Measurements outside this range may be at slightly reduced accuracy due to extrapolation errors.

Options and accessories

Additional sensors can be attached to the CTD, including:

The standard SBE 5M pump may be replaced by an SBE 5P (plastic housing) or 5T (titanium housing) pump for use with dissolved oxygen and/or other pumped sensors. Further details can be found in the manufacturer's SBE 19 plus V2 instrument specification or the SBE 19 and SBE 19 plus user guides.

SeaTech fluorometer S131

This fluorometer is designed to measure in situ chlorophyll- a fluorescence and provide high resolution data for assessment of phytoplankton biomass and monitoring of primary productivity in fresh or marine waters. It's versatility allows the instrument to be deployed on a mooring or in profiling mode. It is not sensitive to ambient light, permitting laboratory calibration with normal room lighting, and field measurements to be made at the water surface.

Specifications

Nominal Chl- a ranges 3, 10, 30, 100, 300 and 1000 µg L -1
Time constant 0.1, 1.0, 3.0 and 10 s
Maximum depth 3000 m
Excitation filter

425 nm peak

200 nm FWHM *

Emission filter

685 nm peak

30 nm FWHM

*FWHM- Full-Width Half-Maximum

Further details can be found in the manufacturer's manual .

SeaTech Transmissometer

Introduction

The transmissometer is designed to accurately measure the the amount of light transmitted by a modulated Light Emitting Diode (LED) through a fixed-length in-situ water column to a synchronous detector.

Specifications

Notes

The instrument can be interfaced to Aanderaa RCM7 current meters. This is achieved by fitting the transmissometer in a slot cut into a customized RCM4-type vane.

A red LED (660 nm) is used for general applications looking at water column sediment load. However, green or blue LEDs can be fitted for specilised optics applications. The light source used is identified by the BODC parameter code.

Further details can be found in the manufacturer's Manual .

RV Scotia 18/2002 CTD Data Documentation

Instrumentation

The instrument used was a Sea-Bird SBE19 SEACAT.

Details of the sensors on the CTD are -

Manufacturer Sensor Serial No. Manufacturer Cal. Date Sensor Units
Sea-Bird Pressure 64240 26 Oct 2000 Decibars
Sea-Bird Temperature 2041 14 Nov 2002 Centigrade
Sea-Bird Conductivity 1615 20 Nov 2002 Siemens/meter
Sea-Bird Oxygen 130411 28 Feb 1996 cm 3 /dm 3
Sea-Tech Fluorometer 131S 01 Apr 1998 Volts
Sea-Tech Transmissometer 238D 02 Aug 1996 Volts

Calibrations

Parameter Value of m (y=mx+c) Value of c (y=mx+c) Equation
Pressure 1.000000 0.000000 P(cal) = P(obs)
Temperature 1.000000 0.000000 T(cal) = T(obs)
Conductivity 0.999966 0.000285 C(cal) = 0.999966C(obs) + 0.000285
Oxygen 1.000000 0.000000 O(cal) = O(obs)
Oxygen Saturation 1.000000 0.000000 OS(cal) = Os(obs)
Fluorescence 0.000227 -0.002315 Chlor.(cal)(ug/l) = 0.000227F(obs)(volts) + -0.002315
Beam Attenuation 1.000000 0.000000 B(cal) = B(obs)

Data Quality Information

In general the data appears to be good. Exceedingly high surface values in attenuance and fluorescence have been flagged. Note that FRS have edited both the temperature and the conductivity channels.

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 1802S
Departure Date 2002-12-04
Arrival Date 2002-12-20
Principal Scientist(s)John Dunn (Fisheries Research Services Aberdeen Marine Laboratory)
Ship FRV Scotia

Complete Cruise Metadata Report is available here


Fixed Station Information

Fixed Station Information

Station NameJONSIS Line
CategoryOffshore route/traverse

Joint North Sea Information System (JONSIS)

As part of the Joint Oceanographic North Sea Data Acquisition Project (JONSDAP), a line of sample stations east of Orkney to the centre of the North Sea was established (1976). This section is commonly known as the JONSIS (Joint Oceanographic North Sea Information System) line and has been sampled annually over the past 30 years. Initially, there were only 10 stations 1-10, two further stations were added, 1a and 6a, in later years.

At present Marine Scotland monitors this line three times a year: Sampling is usually conducted in April, September and December.

These data provide information on long term variations in key variables.
Monitoring data include: Ocean profiles of temperature, salinity and nutrients.

Map of standard stations

BODC image

JONSIS Line stations

Listed below are details of the standard hydrographic stations that form the JONSIS line (start Point on Orkney to the centre of the North Sea). This transect is monitored by Marine Scotland.

Station name Latitude Longitude Depth Spacing
JO 1 59°17.00'N 02°14.00'W 75 m -
JO 1A 59°17.00'N 02°5.00'W 90 m 4.59 nm
JO 2 59°17.00'N 01°56.00'W 100 m 4.59 nm
JO 3 59°17.00'N 01°56.00'W 80 m 4.08 nm
JO 4 59°17.00'N 01°40.00'W 90 m 4.08 nm
JO 5 59°17.00'N 01°30.00'W 95 m 5.10 nm
JO 6 59°17.00'N 01°20.00'W 110 m 5.10 nm
JO 6A 59°17.00'N 01°10.00'W 120 m 5.10 nm
JO 7 59°17.00'N 01°0.00'W 125 m 5.10 nm
JO 8 59°17.00'N 00°40.00'W 120 m 10.20 nm
JO 9 59°17.00'N 00°20.00'W 140 m 10.20 nm
JO10 59°17.00'N 00°0.00'W 135 m 10.20 nm

Other Series linked to this Fixed Station for this cruise - 621533 621545 621557 621569 621570 621582 621594 621601 621613 621637 621649

Other Cruises linked to this Fixed Station (with the number of series) - 0512S (12) 0700S (12) 0703S (12) 0705S_1 (12) 0706S (12) 0709S (12) 1309S (12) 1312S (12) 1402S (12) 1403S (12) 1405S (5) 1506S (12) 1609S (7) 1695S (12) 1712S (12) 1803S (11) 1805S (12) 1906S (12) 2302H (CIR2Y/02) (12)


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