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Metadata Report for BODC Series Reference Number 444394


Metadata Summary

Data Description

Data Category Multiple data types -fixed platform
Instrument Type Bottom Lander (miscellaneous instruments)
Instrument Mounting fixed benthic node
Originating Country Netherlands
Originator -
Originating Organization Royal Netherlands Institute for Sea Research
Processing Status banked
Online delivery of data Download available - Ocean Data View (ODV) format
Project(s) OMEX I
 

Data Identifiers

Originator's Identifier BOBO/OMEX94
BODC Series Reference 444394
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 1994-06-30 22:15
End Time (yyyy-mm-dd hh:mm) 1994-11-12 15:15
Nominal Cycle Interval 1200.0 seconds
 

Spatial Co-ordinates

Latitude 49.18730 N ( 49° 11.2' N )
Longitude 12.82180 W ( 12° 49.3' W )
Positional Uncertainty 5.0 to 10.0 n.miles
Minimum Sensor or Sampling Depth 1451.0 m
Maximum Sensor or Sampling Depth 1452.75 m
Minimum Sensor or Sampling Height 0.25 m
Maximum Sensor or Sampling Height 2.0 m
Sea Floor Depth 1453.0 m
Sea Floor Depth Source -
Sensor or Sampling Distribution Scattered at fixed depths - The sensors are scattered with respect to depth but each remains effectively at the same depth for the duration of the series
Sensor or Sampling Depth Datum Sea floor reference - Depth measured as a height above sea floor but converted into a depth relative to the sea surface according to the same datum as used for sea floor depth (applicable to instrument depths not bathymetric depths)
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)
ATTNMR011per metreAttenuation (red light wavelength) per unit length of the water body by 20 or 25cm path length transmissometer
ATTNMR021per metreAttenuation (red light wavelength) per unit length of the water body by 20 or 25cm path length transmissometer (second sensor)
LCDAEL011Degrees TrueDirection (towards) of water current (Eulerian measurement) in the water body by in-situ current meter and correction to true North
LCDAEL021Degrees TrueDirection (towards) of water current (Eulerian measurement) in the water body by in-situ current meter (second sensor) and correction to true North
LCDAEL031Degrees TrueDirection (towards) of water current (Eulerian measurement) in the water body by in-situ current meter (third sensor) and correction to true North
LCDAEL041Degrees TrueDirection (towards) of water current (Eulerian measurement) in the water body by in-situ current meter (fourth sensor) and correction to true North
LCSAEL011Centimetres per secondSpeed of water current (Eulerian measurement) in the water body by in-situ current meter
LCSAEL021Centimetres per secondSpeed of water current (Eulerian measurement) in the water body by in-situ current meter (second sensor)
LCSAEL031Centimetres per secondSpeed of water current (Eulerian measurement) in the water body by in-situ current meter (third sensor)
LCSAEL041Centimetres per secondSpeed of water current (Eulerian measurement) in the water body by in-situ current meter (fourth sensor)
LCVSAC011Centimetres per secondVertical speed of water current in the water body by in-situ acoustic current meter
LCVSAC021Centimetres per secondVertical speed of water current in the water body by in-situ acoustic current meter beam 2
LCVSAC031Centimetres per secondVertical speed of water current in the water body by in-situ acoustic current meter beam 3
LCVSAC041Centimetres per secondVertical speed of water current in the water body by in-situ acoustic current meter beam 4
PSALPR011DimensionlessPractical salinity of the water body by conductivity cell and computation using UNESCO 1983 algorithm
TEMPPR011Degrees CelsiusTemperature of the water body

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

Scatter plots revealed data to be of suspicious quality and should therefore be used with caution.


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

BODC Current Meter Screening

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

Header information is inspected for:

  • Irregularities such as unfeasible values
  • Inconsistencies between related information. For example:
    • Depths of meter and sea bed.
    • Times for mooring deployment and for start/end of data series.
    • Length of record or number of data cycles, the cycle interval, the clock error and the period over which accrued.
    • Parameters stated as measured and the parameters actually present in the data cycles.
  • Originator's comments on meter/mooring performance and data quality.

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

Data cycles are inspected using time 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 following types of irregularity, each relying on visual detection in the time series plot, are amongst those which may be flagged as suspect:

  • Spurious data at the start or end of the record.
  • Obvious spikes occurring in periods free from meteorological disturbance.
  • A sequence of constant values in consecutive data cycles.

If a large percentage of the data is affected by irregularities, deemed abnormal, then instead of flagging the individual suspect values, a caution may be documented. Likewise documents will highlight irregularities seen in the current vector scatter plots such as incongruous centre holes, evidence of mooring 'knock-down', abnormal asymmetry in tidally dominated records or gaps as when a range of speeds or directions go unregistered due to meter malfunction.

The term 'knock-down' refers to the situation when the 'drag' exerted on a mooring at high current speeds may cause instruments to tilt beyond the angle at which they are intended to operate. At this point the efficiency of the current sensors to accurately record the flow is reduced.

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

  • Maximum and minimum values of parameters (spikes excluded).
  • The orientation and symmetry of the current vector scatter plot.
  • The direction of rotation of the current vectors.
  • The approximate amplitude and periodicity of the tidal currents.
  • The occurrence of meteorological events and, finally, for series for which no time check was possible, the phase.

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.

Sensor Locations

The sensor heights above sea bed and corresponding data channels:

Parameter Height Above Sea Bed Serial Number
ATTNMR02 2.00 m SN178-D
ATTNMR01 1.00 m SN118-D
LCDAEL04 1.00 m  
LCSAEL04 1.00 m  
LCVSAC04 1.00 m  
LCDAEL03 0.75 m  
LCSAEL03 0.75 m  
LCVSAC03 0.75 m  
LCDAEL02 0.50 m  
LCSAEL02 0.50 m  
LCVSAC02 0.50 m  
LCDAEL01 0.25 m  
LCSAEL01 0.25 m  
LCVSAC01 0.25 m  

Project Information

Ocean Margin EXchange (OMEX) I

Introduction

OMEX was a European multidisciplinary oceanographic research project that studied and quantified the exchange processes of carbon and associated elements between the continental shelf of western Europe and the open Atlantic Ocean. The project ran in two phases known as OMEX I (1993-1996) and OMEX II - II (1997-2000), with a bridging phase OMEX II - I (1996-1997). The project was supported by the European Union under the second and third phases of its MArine Science and Technology Programme (MAST) through contracts MAS2-CT93-0069 and MAS3-CT97-0076. It was led by Professor Roland Wollast from Université Libre de Bruxelles, Belgium and involved more than 100 scientists from 10 European countries.

Scientific Objectives

The aim of the Ocean Margin EXchange (OMEX) project was to gain a better understanding of the physical, chemical and biological processes occurring at the ocean margins in order to quantify fluxes of energy and matter (carbon, nutrients and other trace elements) across this boundary. The research culminated in the development of quantitative budgets for the areas studied using an approach based on both field measurements and modeling.

OMEX I (1993-1996)

The first phase of OMEX was divided into sub-projects by discipline:

  • Physics
  • Biogeochemical Cycles
  • Biological Processes
  • Benthic Processes
  • Carbon Cycling and Biogases

This emphasises the multidisciplinary nature of the research.

The project fieldwork focussed on the region of the European Margin adjacent to the Goban Spur (off the coast of Brittany) and the shelf break off Tromsø, Norway. However, there was also data collected off the Iberian Margin and to the west of Ireland. In all a total of 57 research cruises (excluding 295 Continuous Plankton Recorder tows) were involved in the collection of OMEX I data.

Data Availability

Field data collected during OMEX I have been published by BODC as a CD-ROM product, entitled:

  • OMEX I Project Data Set (two discs)

Further descriptions of this product and order forms may be found on the BODC web site.

The data are also held in BODC's databases and subsets may be obtained by request from BODC.


Data Activity or Cruise Information

Data Activity

Start Date (yyyy-mm-dd) 1994-06-30
End Date (yyyy-mm-dd) 1994-11-12
Organization Undertaking ActivityRoyal Netherlands Institute for Sea Research
Country of OrganizationNetherlands
Originator's Data Activity Identifier10_BOBO
Platform Categoryfixed benthic node

OMEX BOBO Lander Deployment 10_BOBO

Site: near OMEX2

Position 49.1873° N, 12.8218° W
Water depth 1453 m
Deployed 08 Jun 1994
from RRS Charles Darwin (CD86)
Recovered 19 Sep 1995
from Pelagia (PLG95B)

Lander BOBO (BOttom BOundary Layer Research) consists of 4 acoustic current meters, a central data storage and command logger, two 25 cm beam SeaTech transmissometers, a conductivity/ temperature logger (SeaCat CT probe) and two underwater cameras with flashing unit.

Instruments positions on the rig

Height above
Sea Bed
Instrument
2.00 m Transmissometer SN178-D
1.00 m Transmissometer SN118-D
1.00 m CT probe
1.00 m Current meter
0.75 m Current meter
0.50 m Current meter
0.25 m Current meter

Cruise

Cruise Name CD86
Departure Date 1994-05-20
Arrival Date 1994-06-13
Principal Scientist(s)Tjeerd van Weering (Royal Netherlands Institute for Sea Research)
Ship RRS Charles Darwin

Complete Cruise Metadata Report is available here


Fixed Station Information

Fixed Station Information

Station NameOMEX I site OMEX2
CategoryOffshore area
Latitude49° 11.46' N
Longitude12° 48.00' W
Water depth below MSL1418.0 m

OMEX I Moored Instrument and CTD site OMEX2

OMEX2 was one of four fixed stations for the OMEX I project. It was visited by twelve cruises and collected a variety of data during the period June 1993 to October 1995. These include:

  • Mooring deployments - Aandeera current meters with transmissometers
  • CTD casts
  • Net trawls
  • Plankton recorders
  • Cores
  • Water samples

The data collected a site OMEX2 lay within a box bounded by co-ordinates 49° 6.72'N, 013° 16.03'W at the southwest corner and 49° 17.2'N, 012° 44.4'W at the northeast corner, with an approximate depth of 1500 metres.

Related Fixed Station activities are detailed in Appendix 1


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: OMEX I site OMEX2

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
444382Multiple data types -fixed platform1993-06-24 20:29:0049.1885 N, 12.7333 WFS Poseidon PO200_7
319390Currents -subsurface Eulerian1993-06-27 11:49:0049.2872 N, 12.8193 WFS Poseidon PO200_7
319389Currents -subsurface Eulerian1993-06-27 12:27:0049.2872 N, 12.8193 WFS Poseidon PO200_7
920244CTD or STD cast1993-06-29 14:29:0049.193 N, 12.944 WValdivia VLD137
920256CTD or STD cast1993-06-29 15:13:0049.179 N, 12.957 WValdivia VLD137
883705CTD or STD cast1993-09-25 07:41:0049.22783 N, 12.80017 WRV Belgica BG9322A
883717CTD or STD cast1993-09-25 12:36:0049.25967 N, 12.80733 WRV Belgica BG9322A
1271492Water sample data1993-09-25 12:53:0049.25973 N, 12.80741 WRV Belgica BG9322A
883729CTD or STD cast1993-09-25 15:46:0049.26067 N, 12.81033 WRV Belgica BG9322A
883730CTD or STD cast1993-09-25 17:22:0049.1975 N, 12.74367 WRV Belgica BG9322A
1271511Water sample data1993-09-25 17:57:0049.1975 N, 12.74369 WRV Belgica BG9322A
883742CTD or STD cast1993-09-25 19:55:0049.23033 N, 12.794 WRV Belgica BG9322A
1271523Water sample data1993-09-25 20:18:0049.23031 N, 12.79403 WRV Belgica BG9322A
914969CTD or STD cast1993-10-21 08:46:0049.18667 N, 12.81967 WRV Pelagia PE093
908153CTD or STD cast1994-01-05 13:06:0049.18333 N, 12.81 WFS Meteor M27_1
908165CTD or STD cast1994-01-05 16:47:0049.17 N, 12.79167 WFS Meteor M27_1
444369Currents -subsurface Eulerian1994-01-11 08:41:0049.1883 N, 12.795 WFS Meteor M27_1
444370Currents -subsurface Eulerian1994-01-11 08:55:0049.1883 N, 12.795 WFS Meteor M27_1
908233CTD or STD cast1994-01-11 17:01:0049.21167 N, 12.88333 WFS Meteor M27_1
887362CTD or STD cast1994-04-16 06:51:0049.4215 N, 12.7765 WRRS Charles Darwin CD85
887301CTD or STD cast1994-04-18 03:36:0049.1445 N, 12.7865 WRRS Charles Darwin CD85
887313CTD or STD cast1994-04-18 05:53:0049.16517 N, 12.768 WRRS Charles Darwin CD85
444321Currents -subsurface Eulerian1994-04-18 13:56:0049.1865 N, 12.8194 WRRS Charles Darwin CD85
444308Currents -subsurface Eulerian1994-04-18 14:04:0049.1865 N, 12.8194 WRRS Charles Darwin CD85
887325CTD or STD cast1994-04-18 21:15:0049.133 N, 12.82217 WRRS Charles Darwin CD85
974033CTD or STD cast1994-05-25 13:50:0049.194 N, 12.745 WRRS Charles Darwin CD86
1663773Water sample data1994-05-25 14:24:0049.19405 N, 12.74502 WRRS Charles Darwin CD86
910378CTD or STD cast1994-09-16 02:37:0049.18333 N, 12.845 WFS Meteor M30_1
442941Currents -subsurface Eulerian1994-09-16 13:10:0049.1912 N, 12.8 WFS Meteor M30_1
442928Currents -subsurface Eulerian1994-09-16 13:14:0049.1912 N, 12.8 WFS Meteor M30_1
885275CTD or STD cast1995-06-12 23:00:0049.2025 N, 12.8185 WRRS Charles Darwin CD94
915008CTD or STD cast1995-08-21 06:15:0049.1865 N, 12.8195 WRV Pelagia PE95A
915162CTD or STD cast1995-09-18 19:37:0049.18983 N, 12.74183 WRV Pelagia PE95B
886475CTD or STD cast1995-10-01 04:24:0049.19567 N, 12.811 WRRS Discovery D217
886358CTD or STD cast1995-10-05 05:00:0049.1875 N, 12.80517 WRRS Discovery D217
886371CTD or STD cast1995-10-05 11:37:0049.191 N, 12.84267 WRRS Discovery D217
1676280Water sample data1995-10-05 12:39:0049.19099 N, 12.84267 WRRS Discovery D217
886383CTD or STD cast1995-10-05 14:53:0049.1955 N, 12.85833 WRRS Discovery D217
1676292Water sample data1995-10-05 15:07:0049.19553 N, 12.85834 WRRS Discovery D217
886229CTD or STD cast1995-10-14 05:20:0049.19217 N, 12.8065 WRRS Discovery D217
1676359Water sample data1995-10-14 05:35:0049.19215 N, 12.80656 WRRS Discovery D217