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Metadata Report for BODC Series Reference Number 476206


Metadata Summary

Data Description

Data Category Fluorescence or pigments
Instrument Type
NameCategories
Chelsea Technologies Group Aquatracka fluorometer  fluorometers
Instrument Mounting moored surface buoy
Originating Country United Kingdom
Originator -
Originating Organization Dunstaffnage Marine Laboratory (now Scottish Association for Marine Science)
Processing Status banked
Online delivery of data Download available - Ocean Data View (ODV) format
Project(s) Land Ocean Interaction Study (LOIS)
LOIS Shelf Edge Study (LOIS - SES)
 

Data Identifiers

Originator's Identifier 013CD93
BODC Series Reference 476206
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 1995-04-17 16:09
End Time (yyyy-mm-dd hh:mm) 1995-05-09 17:02
Nominal Cycle Interval 3600.0 seconds
 

Spatial Co-ordinates

Latitude 56.45300 N ( 56° 27.2' N )
Longitude 9.04620 W ( 9° 2.8' W )
Positional Uncertainty 1.0 to 5.0 n.miles
Minimum Sensor or Sampling Depth 1.0 m
Maximum Sensor or Sampling Depth 1.0 m
Minimum Sensor or Sampling Height 206.0 m
Maximum Sensor or Sampling Height 206.0 m
Sea Floor Depth 207.0 m
Sea Floor Depth Source -
Sensor or Sampling Distribution Fixed common depth - All sensors are grouped effectively at the same depth which is effectively fixed for the duration of 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
AADYAA011DaysDate (time from 00:00 01/01/1760 to 00:00 UT on day)
AAFDZZ011DaysTime (time between 00:00 UT and timestamp)
CPHLPR011Milligrams per cubic metreConcentration of chlorophyll-a {chl-a CAS 479-61-8} per unit volume of the water body [particulate >unknown phase] by in-situ chlorophyll fluorometer
FCNTDC011DimensionlessRaw signal (counts) of instrument output by in-situ chlorophyll fluorometer and dark current baseline correction
FCNTRW011DimensionlessRaw signal (counts) of instrument output by in-situ chlorophyll fluorometer

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

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

Aquatracka fluorometer

The Chelsea Instruments Aquatracka is a logarithmic response fluorometer. It uses a pulsed (5.5 Hz) xenon light source discharging between 320 and 800 nm through a blue filter with a peak transmission of 420 nm and a bandwidth at half maximum of 100 nm. A red filter with sharp cut off, 10% transmission at 664 nm and 678 nm, is used to pass chlorophyll-a fluorescence to the sample photodiode.

The instrument may be deployed either in a through-flow tank, on a CTD frame or moored with a data logging package.

Further details can be found in the manufacturer's specification sheet.

Data Processing Notes

The following calibration was applied:

Chlorophyll (mg/m3) = -0.004744 * dark corrected signal

Fluorometer Data Processing

Data Originator's Processing

The data were logged as raw counts every three minutes which were then averaged over hourly intervals. The time stamp given is the time at the end of the interval. An unusual feature of the data was that the last averaging interval of each month was two hours rather than one hour. The resulting gap in the time channel is real and not an artefact of time channel generation.

The signal (raw counts) was transformed and corrected for dark current using a reading in the dark to give a dark corrected signal.

BODC Data Processing and Quality Control

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

Header information was inspected for:

  1. Irregularities such as unfeasible values.
  2. Inconsistencies between related information. For example:
    • Depths of meter and sea bed
    • Times for mooring deployment/recovery and series start/end
    • Length of record and number of data cycles/cycle interval/clock error
    • Parameters reported in the header and the parameters actually present in the data cycles.
  3. Originator's comments on meter/mooring performance and data quality

Problem Report documents were written by BODC to highlight any problems that cannot be resolved.

Data cycles were inspected using time series plots of all parameters. Any values considered to be erroneous have either been flagged as suspect ('M') or have been documented in a Problem Report.


Project Information

Land Ocean Interaction Study (LOIS)

Introduction

The Land Ocean Interaction Study (LOIS) was a Community Research Project of the Natural Environment Research Council (NERC). The broad aim of LOIS was to gain an understanding of, and an ability to predict, the nature of environmental change in the coastal zone around the UK through an integrated study from the river catchments through to the shelf break.

LOIS was a collaborative, multidisciplinary study undertaken by scientists from NERC research laboratories and Higher Education institutions. The LOIS project was managed from NERC's Plymouth Marine Laboratory.

The project ran for six years from April 1992 until April 1998 with a further modelling and synthesis phase beginning in April 1998 and ending in April 2000.

Project Structure

LOIS consisted of the following components:

  • River-Atmosphere-Coast Study (RACS)
    • RACS(A) - Atmospheric sub-component
    • RACS(C) - Coasts sub-component
    • RACS(R) - Rivers sub-component
    • BIOTA - Terrestrial salt marsh study
  • Land Ocean Evolution Perspective Study (LOEPS)
  • Shelf-Edge Study (SES)
  • North Sea Modelling Study (NORMS)
  • Data Management (DATA)

Marine Fieldwork

Marine field data were collected between September 1993 and September 1997 as part of RACS(C) and SES. The RACS data were collected throughout this period from the estuaries and coastal waters of the UK North Sea coast from Great Yarmouth to the Tweed. The SES data were collected between March 1995 and September 1996 from the Hebridean slope. Both the RACS and SES data sets incorporate a broad spectrum of measurements collected using moored instruments and research vessel surveys.


LOIS Shelf Edge Study (LOIS - SES)

Introduction

SES was a component of the NERC Land Ocean Interaction Study (LOIS) Community Research Programme that made intensive measurements from the shelf break in the region known as the Hebridean Slope from March 1995 to September 1996.

Scientific Rationale

SES was devoted to the study of interactions between the shelf seas and the open ocean. The specific objectives of the project were:

  • To identify the time and space scales of ocean-shelf momentum transmission and to quantify the contributions to ocean-shelf water exchange by physical processes.

  • To estimate fluxes of water, heat and certain dissolved and suspended constituents across a section of the shelf edge with special emphasis on net carbon export from, and nutrient import to, the shelf.

  • To incorporate process understanding into models and test these models by comparison with observations and provide a basis for estimation of fluxes integrated over time and the length of the shelf.

Fieldwork

The SES fieldwork was focussed on a box enclosing two sections across the shelf break at 56.4-56.5 °N and 56.6-56.7 °N. Moored instrument arrays were maintained throughout the experiment at stations with water depths ranging from 140 m to 1500 m, although there were heavy losses due to the intensive fishing activity in the area. The moorings included meteorological buoys, current meters, transmissometers, fluorometers, nutrient analysers (but these never returned any usable data), thermistor chains, colour sensors and sediment traps.

The moorings were serviced by research cruises at approximately three-monthly intervals. In addition to the mooring work this cruises undertook intensive CTD, water bottle and benthic surveys with cruise durations of up to 6 weeks (3 legs of approximately 2 weeks each).

Moored instrument activities associated with SES comprised current measurements in the North Channel in 1993 and the Tiree Passage from 1995-1996. These provided boundary conditions for SES modelling activities.

Additional data were provided through cruises undertaken by the Defence Evaluation and Research Agency (DERA) in a co-operative programme known as SESAME.


Data Activity or Cruise Information

Data Activity

Start Date (yyyy-mm-dd) 1995-04-17
End Date (yyyy-mm-dd) 1995-05-09
Organization Undertaking ActivityProudman Oceanographic Laboratory (now National Oceanography Centre, Liverpool)
Country of OrganizationUnited Kingdom
Originator's Data Activity IdentifierPOLRIG#669
Platform Categorysubsurface mooring

Proudman Oceanographic Laboratory Moored Instrument Rig #669

This rig was deployed as part of the LOIS Shelf-Edge Study at site S200.

Rig position: 56° 27.18'N 09° 02.77'W
Deployed: 17 Apr 1995 15:27
from RRS Charles Darwin (cruise CD92B)
Recovered: 09 May 1995 18:00
onto RRS Charles Darwin (cruise CD93A)

The rig comprised an instrumented toroid mooring and a sub-surface mooring separately anchored but connected by a 300m ground line.

Toroid

The toroid was anchored by 500kg of chain and was fitted with an ARGOS beacon. The instrument package, which was fixed 1m below the surface comprised the following:

Chelsea Instruments Aquatracka fluorometer (#112/2530/013) WS Ocean Systems TRB2 transmissometer (#1760) NAS2 nutrient analyser (#1750)

Sub-surface arm

The instruments were anchored by 1000kg of chain and kept erect by a 48" diameter buoy attached 45m below the sea surface.

Instruments deployed on the rig

Height above
Sea Level
Instrument
150m Aanderaa current meter (#6152)
149m to 109m 40m thermistor chain (#2322)
100m Aanderaa current meter (#10207)
99m to 49m 50m thermistor chain (#2323)
10m Aanderaa current meter (#11047)
fitted with SeaTech transmissometer (#557)
8m NAS2 nutrient analyser (#1751)

Related Data Activity activities are detailed in Appendix 1

Cruise

Cruise Name CD92B
Departure Date 1995-04-13
Arrival Date 1995-05-02
Principal Scientist(s)Anton Edwards (Dunstaffnage Marine Laboratory)
Ship RRS Charles Darwin

Complete Cruise Metadata Report is available here


Fixed Station Information

Fixed Station Information

Station NameLOIS(SES) S200
CategoryOffshore location
Latitude56° 27.14' N
Longitude9° 2.90' W
Water depth below MSL200.0 m

LOIS (SES) Mooring and CTD Site S200

Site S200 was a fixed station where moorings were deployed during the Land-Ocean Interaction Study (LOIS) Shelf Edge Study (SES). It was also one of fourteen CTD sites on repeat section S, across the Hebridean Slope, occupied by cruises between March 1995 and September 1996.

Instrument Deployment History

The following tables summarise the instruments deployed at this site for which data may be available.

1995

Mar Apr May Jun Jul Aug Sep Oct Nov Dec
CM a b c c c c c      
ADCP           a a      
TChn a b c c c c c d d  
Tr a b c c c c c d e e
Fl a b c c c c c d e e
NA a b     c c d      

1996

Jan Feb Mar Apr May Jun Jul Aug
CM       d        
ADCP                
TChn                
Tr       f f f f  
Fl       f f f f  
NA                

Each different letter in the tables above corresponds to an individual instrument record.

Glossary

  • CM = Current meter (Aanderaa or S4)
  • BPR = Bottom pressure recorder
  • ADCP = Acoustic Doppler Current Profiler
  • TChn = Thermistor chain
  • Tr = Transmissometer
  • Fl = Fluorometer
  • NA = Nutrient analyser

Note

  1. Transmissometers may have been fitted to some of the current meters.
  2. Other instruments (colour sensors, STABLE) may have been deployed.
  3. Only periods for which useful data were returned are shown.

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
B nominal value
Q value below limit of quantification

Appendix 1: POLRIG#669

Related series for this Data Activity 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
439588Hydrography time series at depth1995-04-17 15:30:0056.453 N, 9.0462 WRRS Charles Darwin CD92B
439632Hydrography time series at depth1995-04-17 15:30:0056.453 N, 9.0462 WRRS Charles Darwin CD92B
496084Transmittance/attenuance, turbidity, or SPM conc.1995-04-17 15:30:0056.453 N, 9.0462 WRRS Charles Darwin CD92B
431273Currents -subsurface Eulerian1995-04-17 15:35:0056.453 N, 9.0462 WRRS Charles Darwin CD92B
439054Currents -subsurface Eulerian1995-04-17 15:35:0056.453 N, 9.0462 WRRS Charles Darwin CD92B
439355Currents -subsurface Eulerian1995-04-17 15:35:0056.453 N, 9.0462 WRRS Charles Darwin CD92B

Appendix 2: LOIS(SES) S200

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
439576Hydrography time series at depth1995-03-31 20:20:0056.453 N, 9.0462 WRRS Charles Darwin CD91B
439620Hydrography time series at depth1995-03-31 20:20:0056.453 N, 9.0462 WRRS Charles Darwin CD91B
496072Transmittance/attenuance, turbidity, or SPM conc.1995-03-31 20:20:0056.453 N, 9.0462 WRRS Charles Darwin CD91B
431261Currents -subsurface Eulerian1995-03-31 20:25:0056.453 N, 9.0462 WRRS Charles Darwin CD91B
439042Currents -subsurface Eulerian1995-03-31 20:25:0056.453 N, 9.0462 WRRS Charles Darwin CD91B
439226Currents -subsurface Eulerian1995-03-31 20:25:0056.453 N, 9.0462 WRRS Charles Darwin CD91B
476199Fluorescence or pigments1995-03-31 21:02:5656.453 N, 9.0462 WRRS Charles Darwin CD91B
439588Hydrography time series at depth1995-04-17 15:30:0056.453 N, 9.0462 WRRS Charles Darwin CD92B
439632Hydrography time series at depth1995-04-17 15:30:0056.453 N, 9.0462 WRRS Charles Darwin CD92B
496084Transmittance/attenuance, turbidity, or SPM conc.1995-04-17 15:30:0056.453 N, 9.0462 WRRS Charles Darwin CD92B
431273Currents -subsurface Eulerian1995-04-17 15:35:0056.453 N, 9.0462 WRRS Charles Darwin CD92B
439054Currents -subsurface Eulerian1995-04-17 15:35:0056.453 N, 9.0462 WRRS Charles Darwin CD92B
439355Currents -subsurface Eulerian1995-04-17 15:35:0056.453 N, 9.0462 WRRS Charles Darwin CD92B
426130Currents -subsurface Eulerian1995-05-10 13:52:3056.4543 N, 9.0463 WRRS Charles Darwin CD93A
439607Hydrography time series at depth1995-05-10 14:00:0056.4543 N, 9.0463 WRRS Charles Darwin CD93A
439644Hydrography time series at depth1995-05-10 14:00:0056.4543 N, 9.0463 WRRS Charles Darwin CD93A
491891Transmittance/attenuance, turbidity, or SPM conc.1995-05-10 14:01:0056.4543 N, 9.0463 WRRS Charles Darwin CD93A
431285Currents -subsurface Eulerian1995-05-10 14:15:0056.4543 N, 9.0463 WRRS Charles Darwin CD93A
439066Currents -subsurface Eulerian1995-05-10 14:15:0056.4543 N, 9.0463 WRRS Charles Darwin CD93A
439447Currents -subsurface Eulerian1995-05-10 14:15:0056.4543 N, 9.0463 WRRS Charles Darwin CD93A
496096Transmittance/attenuance, turbidity, or SPM conc.1995-05-10 16:30:0056.4482 N, 9.0477 WRRS Charles Darwin CD93A
476102Fluorescence or pigments1995-05-10 17:02:5656.4482 N, 9.0477 WRRS Charles Darwin CD93A
439527Hydrography time series at depth1995-05-10 17:30:0056.4482 N, 9.0477 WRRS Charles Darwin CD93A
476058Fluorescence or pigments1995-07-25 12:02:5756.448 N, 9.046 WRRS Challenger CH120
390272CTD or STD cast1995-07-27 23:33:0056.4587 N, 9.05 WRRS Challenger CH120
444413Currents -subsurface Eulerian1995-08-11 05:37:0056.4458 N, 9.0465 WRRS Challenger CH121A
444185Currents -subsurface Eulerian1995-08-11 08:17:0056.4445 N, 9.0515 WRRS Challenger CH121A
439299Currents -subsurface Eulerian1995-08-11 19:17:3056.453 N, 9.0462 WRRS Challenger CH121A
496140Transmittance/attenuance, turbidity, or SPM conc.1995-08-16 08:00:0056.4477 N, 9.0473 WRRS Challenger CH121A
442363Hydrography time series at depth1995-08-16 08:30:0056.4477 N, 9.0473 WRRS Challenger CH121A
476175Fluorescence or pigments1995-08-16 09:09:2156.4477 N, 9.0473 WRRS Challenger CH121A
444425Currents -subsurface Eulerian1996-02-01 08:17:0056.4604 N, 9.0473 WRRS Challenger CH125A
436290Currents -subsurface Eulerian1996-04-24 13:45:0056.4523 N, 9.0497 WRRS Challenger CH126A
436308Currents -subsurface Eulerian1996-04-24 13:45:0056.4523 N, 9.0497 WRRS Challenger CH126A
439091Currents -subsurface Eulerian1996-04-24 13:45:0056.4523 N, 9.0497 WRRS Challenger CH126A