Metadata Report for BODC Series Reference Number 696295

Metadata Summary

Data Description
Data Category Hydrography time series at depth
Instrument Type
NameCategories
Sea-Bird SBE 37-IM MicroCAT C-T Sensor  water temperature sensor; salinity sensor
Instrument Mounting moored surface buoy
Originating Country United Kingdom
Originator Mr John Howarth
Originating Organization Proudman Oceanographic Laboratory (now National Oceanography Centre, Liverpool)
Processing Status banked
Project(s) Coastal Observatory
 

Data Identifiers

Originator's Identifier MC02010.958
BODC Series Reference 696295
 

Time Co-ordinates(UT)
Start Time (yyyy-mm-dd hh:mm) 2006-03-08 07:40
End Time (yyyy-mm-dd hh:mm) 2006-05-09 12:00
Nominal Cycle Interval 600.0 seconds
 

Spatial Co-ordinates

Latitude 53.53600 N ( 53° 32.2' N )
Longitude 3.36400 W ( 3° 21.8' W )
Positional Uncertainty 0.0 to 0.01 n.miles
Minimum Sensor Depth 10.0 m
Maximum Sensor Depth 10.0 m
Minimum Sensor Height 13.4 m
Maximum Sensor Height 13.4 m
Sea Floor Depth 23.4 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 Instantaneous - Depth measured below water line or instantaneous water body surface
 

Parameters
BODC CODE Rank Units Title
AADYAA01 1 Days Date (time from 00:00 01/01/1760 to 00:00 UT on day)
AAFDZZ01 1 Days Time (time between 00:00 UT and timestamp)
ACYCAA01 1 Dimensionless Sequence number
CNDCPR01 1 Siemens per metre Electrical conductivity of the water body by in-situ conductivity cell
PSALPR01 1 Dimensionless Practical salinity of the water body by conductivity cell and computation using UNESCO 1983 algorithm
TEMPPR01 1 Degrees Celsius Temperature 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

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 SBE37-IM MicroCAT

The SBE 37-IM MicroCAT is a high accuracy conductivity and temperature recorder (pressure optional) with a built in Inductive Modem, which provides reliable, low-cost, real-time data transmission. Designed for moorings and other long-duration, fixed-site deployments, MicroCATs have non-corroding titanium housings rated for operation to 7000 metres or pressure sensor full scale-range.

Communication with the MicroCAT is via a Surface Inductive Modem (SIM) to a computer or data logger. Commands and data are transmitted half-duplex between the SIM and the MicroCAT using DPSK (differential-phase-shift-keyed) telemetry. As a safe guard, the MicroCAT simultaneously backs up the data in its non-volatile internal memory as well as transmitting the data via telemetry.

The MicroCAT's aged and pressure-protected thermistor has a long history of exceptional accuracy and stability (typical drift is less than 0.002 °C per year). Electrical isolation of the conductivity electronics eliminates any possibility of ground-loop noise.

Specifications

  Temperature
(°C)		 Conductivity (S m-1) Optional Pressure
Measurement Range -5 to +35 0 to 7 (0 to 70 mS cm-1) 0 to full scale range: 20 / 100 / 350 / 600 / 1000 / 2000 / 3500 / 7000 metres
Initial accuracy 0.002 0.0003 0.1% of full scale range
Typical Stability 0.0002 0.0003 0.05% of full scale range
Resolution 0.0001 0.00001 0.002% of full scale range
Sensor Calibration +1 to +32 0 to 6; physical calibration over range 2.6 to 6 S m-1, plus zero conductivity (air) Ambient pressure to full scale range in 5 steps
Memory 8 Mbyte non-volatile FLASH memory
Data Storage Converted temperature and conductivity: 5 bytes per sample (2.5 bytes each)
Time: 4 bytes per sample
Pressure (optional): 2 bytes per sample
Real-Time Clock 32,768 Hz TCXO accurate to ±1 minutes year-1
Standard Internal Batteries 10.6 Ampere-hour pack consisting of 12 AA lithium batteries. Provides sufficient capacity for more than 200,000 samples for a typical sampling scheme
Housing Titanium pressure case rated at 7000 metres
Weight (without pressure) In water: 2.4 kg
In air: 4.0 kg

Further information can be found via the following link: Sea-Bird SBE37-IM MicroCAT Datasheet

Data Processing: NOCL SBE Sea-Bird MicroCAT (without pressure)

Data Originator's Processing

The following procedures were carried out before the data were supplied to BODC.

Data were downloaded by the Proudman Oceanographic Laboratory (POL) [since 01 April 2010, the National Oceanography Centre Liverpool (NOCL)] from the instrument logger, and factory calibrations were applied to the temperature and conductivity channels. The instruments are returned to the manufacturer for recalibration approximately every two years.

The data were then reformatted by POL/NOCL to a standard ASCII format for display on the Coastal Observatory website. The originator carried out limited quality control checks, which involved looking for obvious anomalies in the data, cross-checking against other datasets and timing checks.

BODC Data Processing

The data files (ASCII format) were downloaded by BODC from the Coastal Observatory web site. The files were reformatted to QXF format using BODC transfer function 318. The following table shows how the originator's variables were mapped to appropriate BODC parameter codes:

Originator's Variable Units Description BODC Parameter Code Units Comments
Temperature °C Temperature of the water column TEMPPR01 °C Data supplied as ITS-90
Conductivity S m-1 Electrical conductivity of the water column by in-situ conductivity cell CNDCPR01 S m-1 -
- - Practical salinity of the water column by conductivity cell and computation using UNESCO 1983 algorithm PSALPR01 - Derived during transfer from MATLAB Seawater Toolbox program 'sw_salt'. This uses UNESCO 1983 algorithm (see reference)

Salinity calculation

Salinity (PSS-78) was computed during transfer using the MATLAB sw_salt routine:

where

Quality control

The reformatted data were visualised using the in-house EDSERPLO software. Suspect and missing data were marked by adding appropriate quality control flags.

References

Fofonoff, N.P., and R.C. Millard Jr., 1983 "Algorithms for computation of fundamental properties of seawater", UNESCO technical paper in marine science 44, 53pp.

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

Proudman Oceanographic Laboratory Coastal Observatory

The Coastal Observatory was established by Proudman Oceanographic Laboratory as a coastal zone real time observing and monitoring system. The main objective is to understand a coastal sea's response both to natural forcing and to the consequences of human activity. Near real-time measurements will be integrated with coupled models into a pre-operational coastal prediction system whose results will be displayed on the World Wide Web.

The Observatory is expected to grow and evolve as resources and technology allow, all the while building up long time series. A site selection pilot study was carried out in September 2001 and the Observatory became operational in August 2002.

The site is located in Liverpool Bay and is subject to typical coastal sea processes, with strong tides, occasional large storm surges and waves, freshwater input, stable and unstable stratification, high suspended sediment concentration and biogeochemical interaction. Measurements and monitoring will focus on the impacts of storms, variations in river discharge (especially the Mersey), seasonality and blooms in Liverpool Bay.

A variety of methods will be used to obtain measurements, including:

  1. Moored instruments for in situ time series of currents, temperature and salinity profiles, and surface waves and meteorology. It is hoped that turbidity and chlorophyll measurements will be made at another site as the Observatory progresses;
  2. The Cefas Smartbuoy for surface properties such as nutrients and chlorophyll, starting late 2002;
  3. R.V. Prince Madog to carry out spatial surveys and service moorings;
  4. Instrumented ferries for near surface temperature, salinity, turbidity, chlorophyll and nutrients. The first route will be Liverpool to Douglas, Isle of Man, starting late 2002;
  5. Drifters for surface currents and properties such as temperature and salinity, starting in 2004;
  6. Tide gauges, with sensors for meteorology, waves, temperature and salinity, where appropriate;
  7. Meteorological data from Bidston Observatory, HF radar and tide gauge sites;
  8. Shore-based HF radar measuring waves and surface currents out to a range of 50 km, starting in 2003;
  9. Satellite data, with infrared for sea surface temperature and visible for chlorophyll and suspended sediment.

The partners currently involved with the project are listed below:

A summary of Coastal Observatory cruises to date on R.V. Prince Madog is given in the table below:

Year No. of cruises Work summary
2001 1 Site selection and pilot study. 95 CTD casts.
2002 4 POL moorings deployed and serviced
Cefas Waverider and SmartBuoy deployed and serviced
103 CTD casts
2003 10 POL moorings serviced
Cefas Waverider and SmartBuoy serviced
341 CTD/LISST casts
2004 9 POL moorings serviced
Cefas Waverider and SmartBuoy serviced
347 CTD/LISST casts
2005 9 POL moorings serviced
Cefas Waverider and SmartBuoy serviced
268 CTD/LISST casts
2006 11 POL moorings serviced
Cefas Waverider and SmartBuoy serviced
508 CTD/LISST casts
2007 9 POL moorings serviced
Cefas Waverider and SmartBuoy serviced
471 CTD/LISST casts
2008 9 POL moorings serviced
Cefas Waverider and SmartBuoy serviced
260 CTD/LISST casts
2009 7 POL moorings serviced
Cefas Waverider and SmartBuoy serviced
213 CTD/LISST casts
2010 8 POL moorings serviced
Cefas Waverider and SmartBuoy serviced
268 CTD/LISST casts
2011 6 POL moorings serviced
Cefas Waverider and SmartBuoy serviced
307 CTD/LISST casts to date, ongoing

Data Activity or Cruise Information

Data Activity

Start Date (yyyy-mm-dd) 2006-03-08
End Date (yyyy-mm-dd) 2006-05-09
Organization Undertaking ActivityCentre for Environment, Fisheries and Aquaculture Science Lowestoft Laboratory
Country of OrganizationUnited Kingdom
Originator's Data Activity IdentifierLB1_031/958
Platform Categorymoored surface buoy

SmartBuoy deployment LB1_031/POLRIG958

Deployment and Recovery

The mooring was deployed in collaboration between Cefas and POL Liverpool Bay Coastal Observatory. The rig was deployed during R.V. Prince Madog PD09_06. This cruise was a joint venture between Liverpool Bay Coastal Observatory and POL Dee Estuary Experiment. Recovery of the rig took place during R.V. Prince Madog cruise PD16_06.

Deployment details are given in the table below. Date and time are in Universal Time (UT) and are displayed in the ISO format YYYY-MM-DD hh:mm.


Rig Position 53° 32.156' N, 3° 21.843' W
Water Depth 21.1 m
Deployed (UT) 2006-03-08 06:35
Recovered (UT) 2006-05-09 14:30
No. of days 62

Rig Description

This rig is a single line mooring, comprising a surface Cefas SmartBuoy with POL instrumentation attached at depth on the mooring line. The single point mooring was mainly composed of 0.5 inch long link chain and marked at the surface by a 1.8 m diameter toroid (the Cefas SmartBuoy) and anchored by a half tonne clump of scrap chain. The Cefas SmartBuoy contains a suite of instruments mounted just below the surface.

The table below details the Cefas instrumentation.


Instrument Serial
Number		 Parameters Meter
depth (m)		 Record
Length (days)
Seapoint Fluorometer 2211 Fluorescence 1 45
Falmouth Scientific OEM CT sensor 1841 Temperature
Salinity		 1 62
Seapoint Turbidity meter 1679 Turbidity
Suspended Load		 1 49
LI-COR-192 Underwater Quantum sensor 13 PAR
Vertical Light attenuation coefficient		 1 37
LI-COR-192 Underwater Quantum sensor 18 PAR 2 45
EnviroTech WMS-2 Aqua Monitor water sampler 2328 Silicate
Total Oxidised Nitrogen		 1 57
EnviroTech NAS in situ nutrient analyser 2405 Total Oxidised Nitrogen 1 26
Aanderaa Oxygen Optode 128 Oxygen Concentration
Oxygen Saturation		 1 62

The table below details the POL instrumentation.

Instrument Serial Number Meter Level Parameters Measured Sampling Interval Comments
Sea-Bird MicroCAT SBE37-IM V2.1 2081 5 m below surface Temperature
Conductivity		 10 minutes Upon recovery the clock was found be to running 7 s fast.
Sea-Bird MicroCAT SBE37-IM V2.1 2010 10 m below surface Temperature
Conductivity		 10 minutes Upon recovery the clock was found be to running 26 s fast.

Other Series linked to this Data Activity - 700462 700498 700345 700413 696302 700529 700622 700554 700591

Cruise

Cruise Name PD09/06
Departure Date 2006-03-06
Arrival Date 2006-03-09
Principal Scientist(s)Alejandro J Souza (Proudman Oceanographic Laboratory)
Ship RV Prince Madog

Complete Cruise Metadata Report is available here

Fixed Station Information

Fixed Station Information

Station NameCOA
CategoryOffshore area
Latitude53° 31.51' N
Longitude3° 23.00' W
Water depth below MSL26.0 m

Liverpool Bay Coastal Observatory Mooring Site A (COA/Site 1/Site 9)

This station is the main mooring site for the Proudman Oceanographic Laboratory (POL) Liverpool Bay Coastal Observatory and was first occupied in 2002. It is also known both as Coastal Observatory Site 1 and Site 9. POL perform two main types of activities at this station: they deploy moorings; and in addition, they take CTD profiles during each site visit. The station lies within a box of mean water depth 22.5 m with the following co-ordinates:

Box Corner Latitude (+ve North) Longitude (+ve East)
North-west corner 53.54097 -3.42958
South-east corner 53.50945 -3.33714

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

2011

Rig Type Typical Instruments Rig IDs Comment
Frame ADCP, CTD, OBS, OXY 1117 for January cruise. Other frame IDs not available at this time. January - September
SmartBuoy CTD x 2, AC-S, CT x 2, FL x 3, OBS x 2, PAR x 2, WMS, NAS, OXY, T x 2 1116 for January cruise. Other frame IDs not available at this time. January - September
SparBuoy AC-S, FL, CTD x 2, T Frame ID not available at this time. September

2010

Rig Type Typical Instruments Rig IDs Comment
Frame ADCP, CTD, ADV, OBS 1086, 1090, 1094, 1098, 1102, 1106, 1109 January - December
SmartBuoy CT x 2, FL x 2, OBS, PAR x 2, WMS, NAS, CTD, OXY, BD, T 1085, 1089, 1093, 1097, 1101, 1105, 1108, 1112 January - December

2009

Rig Type Typical Instruments Rig IDs Comment
Frame ADCP, CTD, ADV, OBS 1055, 1062, 1067, 1071, 1074, 1078, 1082 January - December
SmartBuoy CT x 2, FL x 2, OBS, PAR x 2, WMS, NAS, CTD, OXY, BD, T 1054, 1061, 1066, 1070, 1073, 1077, 1081 January - December

2008

Rig Type Typical Instruments Rig IDs Comment
Frame ADCP, CTD, ADV, OBS 1024, 1028, 1032, 1036, 1041, 1044, 1047, 1051 January - December
SmartBuoy CT x 2, FL x 2, OBS, PAR x 2, WMS, NAS, CTD, OXY, BD, T LB1_047/1023, LB1_048/1027, LB1_049/1031, LB1_050/1035, 1040, 1043, LB1_053/1050 January - December

2007

Rig Type Typical Instruments Rig IDs Comment
Frame ADCP, CTD, ADV, OBS 990, 997, 1001, 1005, 1010, 1014, 1017, 1021 January - December
SmartBuoy CT x 2, FL x 2, OBS, PAR x 2, WMS, NAS, CTD, OXY, BD, T LB1_039/989, LB1_040/996, LB1_041/1000, LB1_042/1004, LB1_043/1009, LB1_044/1013, LB1_045/1016, LB1_046/1020 January - December

2006

Rig Type Typical Instruments Rig IDs Comment
Frame ADCP, CTD, ADV, OBS 951, 962, 966, 970, 974, 978, 982, 986 January - December
SmartBuoy CT x 2, FL x 2, OBS, PAR x 2, WMS, NAS, CTD, OXY, BD 958, 961, 965, 969, 973, 977, LB1_037/981, LB1_038/985 January - December

2005

Rig Type Typical Instruments Rig IDs Comment
Frame ADCP, CT 913, 914, 921, 925, 929, 933, 938, 942, 945, 949 January - December
SmartBuoy CT, FL, OBS, PAR, WMS, NAS, OXY 912, 920, 924, 928, 932, 937, LB1_028/941, LB1_029/944, LB1_030/948 January - December
Frame with telemetry buoy ADCP 914 March - April

2004

Rig Type Typical Instruments Rig IDs Comment
Frame BPR, ADCP, TR, CT 890, 892, 893, 896, 898, 900, 902, 904, 907, 908, 910, 911 January - December
SmartBuoy CT, FL, OBS, PAR, WMS, NAS 889, 891, 895, 897, 899, 901, 903, 906, 909 January - December
Frame with telemetry buoy ADCP 893, 908, 911 April - May, October - December

2003

Rig Type Instruments Rig IDs Comment
Frame BPR, ADCP, TR, CT 861, 864, 866, 869, 872, 878, 880, 883, 885, 887, 888 January - December
SmartBuoy CT, FL, OBS, PAR, WMS, NAS 863, 865, 867, 870, 871, 877, 879, 882, 884, 886 January - December

2002

Rig Type Instruments Rig IDs Comment
Frame BPR, ADCP, TR, CT 851, 854, 856, 858 August - December
Line mooring CT x 3 853, 855 August - November
SmartBuoy CT, FL, OBS, PAR, WMS, NAS 857, 860 November - December

2001

Rig Type Instruments Rig IDs Comment
Frame ADCP, OBS 838, 839, 840, 841, 843, 844, 845, 846, 848, 849 September

CTD Sampling History

Year Number of Cruises Total Casts per year
2011 6 116 including a 46 cast tidal cycle from 2011-04-18 to 2011-04-19 and a 51 cast tidal cycle station from 2011-07-27 to 2011-07-28
2010 7 69 including a 52 cast tidal cycle station from 2010-04-28 to 2010-04-29
2009 7 21
2008 9 75 including a 54 cast tidal cycle station from 2008-05-13 to 2008-05-14
2007 8 71 including a 51 cast tidal cycle station from 2007-05-15 to 2007-05-16
2006 9 72 including a 53 cast tidal cycle station from 2006-05-09 to 2006-05-10
2005 9 41 including a 22 cast tidal cycle station from 2005-04-05 to 2005-04-06
2004 9 77 including a 54 cast tidal cycle station from 2004-05-11 to 2004-05-12
2003 10 28
2002 4 13

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

AC-S = Absorption and attenuation spectrophotometer
ADCP = Acoustic Doppler Current Profiler
ADV = Acoustic Doppler Velocimeter
BD = Bacterial degradation experiment
BPR = Bottom Pressure Recorder
CT = Conductivity and temperature logger
CTD = Conductivity, temperature, depth sensor
FL = Fluorometer
NAS = in-situ nutrient analyser
OBS = Optical Backscatter Turbidity meter
OXY = Oxygen sensor
PAR = PAR sensor
T = Temperature logger
TR = Transmissometer
WMS = Automatic water sampler

Other Series linked to this Fixed Station for this cruise - 696302 696375 700345 700413 700462 700498 700529 700554 700591 700622

Other Cruises linked to this Fixed Station (with the number of series) - PD01/08 (16) PD02/03 (4) PD02/05 (3) PD02/07 (14) PD02/09B (16) PD02/10 (9) PD05/10 (10) PD06/07 (15) PD07/08 (14) PD09/06 (10) PD09/07 (63) PD09/08 (15) PD10/03 (3) PD10/10 (8) PD11/05 (1) PD11/11 (48) PD12/05 (2) PD12/09 (10) PD13/07 (13) PD14/08 (67) PD16/06 (8) PD16/07 (14) PD17/03 (4) PD17/10 (9) PD18/04 (5) PD18/05 (3) PD18/09 (11) PD19/08 (2) PD20/02 (5) PD20/06 (8) PD20/07 (16) PD21/05 (3) PD21/10 (9) PD22/04 (5) PD22/06 (8) PD23/03A (4) PD23/07 (15) PD23/08 (12) PD24/02 (1) PD24/09 (11) PD25/03B (4) PD25/05 (3) PD25/06 (8) PD25/11 (4) PD27/07 (16) PD29/04 (4) PD29/06 (8) PD29/08 (13) PD29/10 (11) PD30/05 (2) PD31/02 (4) PD31/03 (4) PD32/04 (4) PD33/08 (4) PD33/09 (10) PD34/03 (4) PD34/05 (9) PD35/02 (4) PD35/06 (13) PD36/10 (10) PD37/06 (13) PD37/08 (17) PD38/03 (5) PD38/04 (4) PD38/09 (10) PD41/05 (10) PD43/11 (3) PD47/09 (9) PD48/05 (10) PD49/10 (7)

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