Metadata Report for BODC Series Reference Number 1024706


Metadata Summary

Data Description

Data Category Transmittance/attenuance, turbidity, or SPM conc.
Instrument Type
NameCategories
Seapoint chlorophyll fluorometer  fluorometers
Instrument Mounting moored surface buoy
Originating Country United Kingdom
Originator Dr Naomi Greenwood
Originating Organization Centre for Environment, Fisheries and Aquaculture Science Lowestoft Laboratory
Processing Status banked
Project(s) Oceans 2025 Theme 10 SO11
 

Data Identifiers

Originator's Identifier LB2_028_FT_1550
BODC Series Reference 1024706
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 2008-09-10 17:30
End Time (yyyy-mm-dd hh:mm) 2008-10-07 23:30
Nominal Cycle Interval 1800.0 seconds
 

Spatial Co-ordinates

Latitude 53.44800 N ( 53° 26.9' N )
Longitude 3.64220 W ( 3° 38.5' W )
Positional Uncertainty 0.1 to 0.5 n.miles
Minimum Sensor Depth 1.0 m
Maximum Sensor Depth 1.0 m
Minimum Sensor Height 25.8 m
Maximum Sensor Height 25.8 m
Sea Floor Depth 26.8 m
Sensor Distribution Fixed common depth - All sensors are grouped effectively at the same depth which is effectively fixed for the duration of the series
Sensor Depth Datum Approximate - Depth is only approximate
Sea Floor Depth Datum Approximate - Depth is only approximate
 

Parameters

BODC CODE Rank Units Short Title Title
AADYAA01 1 Days Date(Loch_Day) Date (time from 00:00 01/01/1760 to 00:00 UT on day)
AAFDZZ01 1 Days Time(Day_Fract) Time (time between 00:00 UT and timestamp)
ACYCAA01 1 Dimensionless Record_No Sequence number
TSEDBSCL 1 Milligrams per litre Tot_SPM_BS+Cal Concentration of suspended particulate material {SPM} per unit volume of the water body [particulate >unknown phase] by in-situ optical backscatter measurement and calibration against sample data
TURBSP01 1 Nephelometric Turbidity Units Turb Turbidity of the water body by SeaPoint turbidity meter and laboratory calibration against formazin
 

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

Seapoint Chlorophyll Fluorometer

The Seapoint Chlorophyll Fluorometer (SCF) is a low power instrument for in situ measurements of chlorophyll a. The SCF uses modulated blue LED lamps and a blue excitation filter to excite chlorophyll a. The fluorescent light emitted by the chlorophyll a passes through a red emission filter and is detected by a silicon photodiode. The low level signal is then processed using synchronous demodulation circuitry which generates an output voltage proportional to chlorophyll a concentration. The SCF may be operated with or without a pump.

Sensor specifications, current at August 2006, are given in the table below. More information can be found at the manufacturer's web site .

Sensor Specifications

Power requirements 8 - 20 VDC, 15 mA avg., 27 mA pk.
Output 0 - 5.0 VDC
Output Time Constant 0.1 sec.
Power-up transient period < 1 sec.
Excitation Wavelength 470 nm CWL, 30 nm FWHM
Emission Wavelength 685 nm CWL, 30 nm FWHM
Sensing Volume 340 mm 3
Minimum Detectable Level 0.02 µg l -1

  Gain Sensitivity, V µg -1 l -1 Range, µg l -1
Sensitivity/Range 30x
10x
3x
1x
1.0
0.33
0.1
0.033
5
15
50
150

Seapoint Turbidity Meter

The Seapoint Turbidity Meter detects light scattered by particles suspended in water, generating an output voltage proportional to turbidity or suspended solids. Range is selected by two digital lines which can be hard wired or microprocessor controlled, thereby choosing the appropriate range and resolution for measurement of extremely clean to very turbid waters. The offset voltage is within 1 mV of zero and requires no adjustment across gains. The optical design confines the sensing volume to within 5 cm of the sensor allowing near-bottom measurements and minimizing errant reflections in restricted spaces.

Sensor specifications, current at August 2006, are given in the table below.

Sensor Specifications

Power requirements 7 - 20 VDC, 3.5 mA avg., 6 mA pk.
Output 0 - 5.0 VDC
Output Time Constant 0.1 sec.
RMS Noise> < 1 mV
Power-up transient period < 1 sec.
Light Source Wavelength 880 nm
Sensing Distance (from windows) < 5 cm (approx.)
Linearity < 2% deviation 0 - 750 FTU

  Gain Sensitivity (mV FTU -1 ) Range (FTU)
Sensitivity/Range 100x
20x
5x
1x
200
40
10
2
25
125
500
**

** output is non-linear above 750 FTU.

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

Cefas SmartBuoy data processing

This document outlines the procedures in place at Cefas in August 2005 for processing and quality assuring SmartBuoy data.

Raw data files are processed and the data move through 4 levels, starting with raw data at level 0 through to level 3, where data are fully quality-assured and expressed in appropriate units. The application of the procedures at each level result in data deemed fit to progress to the next level.

Cefas Quality Assurance (QA) Protocols

At Level 0, raw binary data files from the loggers are transferred to the network.

Automated checks - Level 1

Level 1 involves applying automated quality assurance procedures to the data. These include the following steps:

The data are now at QA status = 1.

Manual checks - Level 2

Level 1 burst mean data are now ready for manual QA procedures in order to progress to Level 2. Deployment notes are consulted for any comments on sensor performance or malfunction and post-deployment photographs of sensors, if available, are examined.

Cefas use a data visualisation tool to examine the SmartBuoy data.

Calibrations - Level 3

The combined information from Level 2 is used to determine the periods during which the data series are considered suspect. The data have now reached QA status = 2 and can progress to Level 3, where they will be fully calibrated with field-derived sample data.

The data have now reached QA status = 3 as time stamped, field calibrated burst mean data with parameter codes and units stored on SmartBuoy database with associated uncertainty or 95% confidence limits as appropriate. All SmartBuoy data banked at BODC have passed full Cefas QA procedures. Data that fail the Cefas QA checks are not submitted for banking.

SmartBuoy data processing by BODC

The following outlines the procedures that take place at BODC for banking Cefas SmartBuoy data.

BODC receives SmartBuoy data from Cefas after all quality checks have been passed and all possible calibrations applied. The data files are submitted as separate MS Excel spreadsheets for each parameter, i.e. there are separate files for temperature and salinity from the same instrument. An exact copy of the data is archived for safekeeping upon arrival.

Once the submitted data files are safely archived, the data undergo standard reformatting and banking procedures:


Project Information

Oceans 2025 Theme 10, Sustained Observation Activity 11: Liverpool Bay and Irish Sea Coastal Observatory

Sustained, systematic observations of the ocean and continental shelf seas at appropriate time and space scales allied to numerical models are key to understanding and prediction. In shelf seas these observations address issues as fundamental as 'what is the capacity of shelf seas to absorb change?' encompassing the impacts of climate change, biological productivity and diversity, sustainable management, pollution and public health, safety at sea and extreme events. Advancing understanding of coastal processes to use and manage these resources better is challenging; important controlling processes occur over a broad range of spatial and temporal scales which cannot be simultaneously studied solely with satellite or ship-based platforms.

Considerable effort has been spent by the Proudman Oceangraphic Laboratory (POL) in the years 2001 - 2006 in setting up an integrated observational and now-cast modelling system in Liverpool Bay (see Figure), with the recent POL review stating the observatory was seen as a leader in its field and a unique 'selling' point of the laboratory. Cost benefit analysis (IACMST, 2004) shows that benefits really start to accrue after 10 years. In 2007 - 2012 exploitation of (i) the time series being acquired, (ii) the model-data synthesis and (iii) the increasingly available quantities of real-time data (e.g. river flows) can be carried out through Sustained Observation Activity (SO) 11, to provide an integrated assessment and short term forecasts of the coastal ocean state.

BODC image

Overall Aims and Purpose of SO 11

Measurement and Modelling Activities

More detailed information on this Work Package is available at pages 32 - 35 of the official Oceans 2025 Theme 10 document: Oceans 2025 Theme 10

Weblink: http://www.oceans2025.org/

References:

IACMST., 2004. The Economics of Sustained Marine Measurements. IACMST Information Document, N0.11, Southampton: IACMST, 96 pp


Data Activity or Cruise Information

Data Activity

Start Date (yyyy-mm-dd) 2008-09-10
End Date (yyyy-mm-dd) 2008-12-11
Organization Undertaking ActivityProudman Oceanographic Laboratory (now National Oceanography Centre, Liverpool)
Country of OrganizationUnited Kingdom
Originator's Data Activity IdentifierPOLRIG1045
Platform Categorymoored surface buoy

Smartbuoy deployment LB2_028 / POLRIG#1045

Deployment and Recovery

This SmartBuoy rig was deployed in a collaboration between Cefas and POL at Liverpool Bay Coastal Observatory Site B. Recovery was planned to take place during October cruise PD33_08, however poor weather conditions during the cruise meant that recovery was postponed until the December cruise, PD37_08.

Deployment cruise RV Prince Madog cruise PD29/08
Recovery cruise RV Prince Madog cruise PD37/08
Rig position 53° 26.889'N 3° 38.639'W
Water Depth 26.8 m

Rig Description

The Cefas SmartBuoy carried a suite of instruments mounted just below the surface, as well as instrumentation belonging to POL at between 5 and 15 metres below the surface. The frame was also fitted with bags for the determination of bacterial degradation. The single point mooring was composed mainly of 1/2" long link chain, marked by a 1.8 m diameter toroid and anchored by a half tonne clump of scrap chain. Further information about the instrument suite is given in the table below.

Instrument Serial
Number
Meter
depth (m)
Comment
Chelsea Instruments Minitracka Fluorometer 175063 1 Cefas instrument
Falmouth Scientific OEM CT sensor 1401 1 Cefas instrument
Seapoint Turbidity meter 1550 1 Cefas instrument
Sea-Bird MicroCAT
SM V 2.6b
5791 5 POL instrument
Sea-Bird MicroCAT
SM V 2.6b
5433 10 POL instrument
Star Oddi Starmon mini 2847 7.5 POL instrument.
Star Oddi Starmon mini 2849 15 POL instrument.

Other Series linked to this Data Activity - 939300 1024626 939232 1024546 939244 939312

Cruise

Cruise Name PD29/08
Departure Date 2008-09-10
Arrival Date 2008-09-11
Principal Scientist(s)Phil J Knight (Proudman Oceanographic Laboratory)
Ship RV Prince Madog

Complete Cruise Metadata Report is available here


Fixed Station Information

Fixed Station Information

Station NameCoastal Observatory Site 21
CategoryOffshore location
Latitude53° 27.13' N
Longitude3° 38.48' W
Water depth below MSL25.0 m

Liverpool Bay Coastal Observatory Site 21

This station is one of 34 stations regularly visited by the Proudman Oceanographic Laboratory (POL) as part of the Liverpool Bay Coastal Observatory. The main activity at this site are CTD profiles (since August 2002) which are taken during each site visit. This station was also the secondary mooring site (also referred to as Site B) for the Coastal Observatory project between April 2005 and March 2010. After March 2010 the moorings were moved to site 20. The station lies within a box of mean water depth 24 m with the following co-ordinates:

Box Corner Latitude (+ve North) Longitude (+ve East)
North-west corner 53.46028 -3.658
South-east corner 53.44249 -3.6105

The position of this station relative to the other POL Coastal Observatory sites can be seen from the figure below.

BODC image

Mooring Deployment History

2010

Rig Type Typical Instruments Rig IDs Comment
Frame ADCP, CTD, OBS, Telemetry ADCP 1088, 1092, 1096, 1100, 1104, 1107, 1111 January - December
SmartBuoy CT, FL, OBS, BD 1087, 1091, 1095, 1099, 1103, 1110, 1115 January - December

2009

Rig Type Typical Instruments Rig IDs Comment
Frame ADCP, CTD, OBS, Telemetry ADCP 1057, 1065, 1069, 1072, 1076, 1080, 1084 January - December
SmartBuoy CT, FL, OBS, BD 1056, 1064, 1068, 1075, 1079, 1083 January - December

2008

Rig Type Typical Instruments Rig IDs Comment
Frame ADCP, CTD, OBS, Telemetry ADCP 1026, 1030, 1033, 1038, 1053 January - December
SmartBuoy CT, FL, OBS, BD LB2_023/1025, LB2_024/1029, LB2_025/1034, LB2_026/1037, LB2_029/1052 January - December

2007

Rig Type Typical Instruments Rig IDs Comment
Frame ADCP, CTD, OBS, Telemetry ADCP 992, 999, 1002, 1007, 1012, 1019 January - December
SmartBuoy CT, FL, OBS, BD 991, LB2_016/998, LB2_017/1003, LB2_018/1006, LB2_019/1011, LB2_020/1015, LB2_021/1018, LB2_022/1022 January - December

2006

Rig Type Typical Instruments Rig IDs Comment
Frame ADCP, CTD, OBS, Telemetry ADCP 952, 960, 964, 968, 972, 976, 980, 984, 988 January - December
SmartBuoy CT, FL, OBS, BD LB2_006, LB2_007, LB2_008, LB2_009, LB2_010, LB2_011, LB2_012, LB2_013/983, LB2_014/987 January - December

2005

Rig Type Typical Instruments Rig IDs Comment
Frame ADCP, CTD, OBS 923, 927, 931, 936, 940, 943, 947, 950 January - December
SmartBuoy CT, FL, OBS, WMS LB2_001/926, LB2_002/930, LB2_003/935, LB2_004/939, LB2_005/946 May - December
Marker buoy CT 922 April - May

CTD Sampling History

Year Number of Cruises Total Casts per year
2011 5 5
2010 6 6
2009 7 18
2008 9 16
2007 8 17
2006 9 18
2005 9 14
2004 8 8
2003 9 9
2002 2 2

The CTD instrument package for these cruises was a Sea-Bird 911plus, with beam transmissometer, fluorometer, LICOR PAR sensor, LISST-25, and oxygen sensor.

Key

ADCP = Acoustic Doppler Current Profiler
BD = Bacterial degradation experiment
CT = Conductivity and temperature logger
CTD = Conductivity, temperature, depth sensor
FL = Fluorometer
OBS = Optical Backscatter Turbidity meter
Telemetry ADCP = ADCP sending data back to shore in real-time
WMS = Automatic water sampler

Other Series linked to this Fixed Station for this cruise - 939219 939232 939244 939300 939312 1024546 1024626 1623617

Other Cruises linked to this Fixed Station (with the number of series) - PD01/08 (12) PD01/11 (1) PD02/07 (4) PD02/09B (11) PD02/10 (1) PD04/06 (4) PD04/07 (4) PD06/07 (9) PD07/08 (9) PD07/11 (1) PD09/07 (9) PD09/08 (11) PD11/05 (3) PD11/11 (1) PD12/06 (4) PD12/09 (11) PD13/07 (11) PD14/08 (10) PD16/06 (4) PD16/07 (10) PD17/10 (5) PD18/05 (8) PD18/09 (10) PD19/08 (2) PD20/06 (4) PD20/07 (7) PD21/05 (8) PD21/10 (1) PD22/06 (4) PD23/07 (10) PD23/08 (7) PD24/09 (5) PD25/05 (8) PD25/06 (4) PD27/07 (9) PD29/06 (4) PD29/10 (1) PD30/05 (7) PD33/08 (1) PD33/09 (12) PD34/05 (2) PD35/06 (7) PD36/10 (1) PD37/06 (7) PD37/08 (11) PD38/09 (9) PD41/05 (6) PD43/11 (1) PD47/09 (11) PD48/05 (2) PD49/10 (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