Metadata Report for BODC Series Reference Number 696547

• Metadata Summary

• Problem Reports

• Data Access Policy

• Narrative Documents

• Project Information

• Data Activity or Cruise Information

• Fixed Station Information

• BODC Quality Flags

• SeaDataNet Quality Flags

Metadata Summary

Problem Reports

No Problem Report Found in the Database

Originator's data processing/quality comments for RIG#946/MicroCAT#02506

Data supplied to BODC were accompanied by data quality notes from the Originator that detailed observations made when the data were processed and subsequent processing decisions. A summary of these notes have been provided in the tables below.

Rig#946

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

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

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

Coastal Observatory Sea-Bird MicroCAT Data Processing

Data Originator's Processing

After the mooring was recovered, the data were downloaded from the instrument logger, and factory calibrations were applied to the conductivity, temperature and pressure channels, when present.

Before the data were supplied to BODC, basic quality control was performed by the Data Originator. The first stage of quality checks involved comparing the data from each instrument with CTD measurements recorded during the deployment and recovery of the mooring. Following the comparison against CTD data secondary checks were performed by comparing the data from each instrument against the data from other sensors attached to that mooring. The Originator has provided BODC with a document containing a full description of their quality control methodology. Depending on the result of the quality checks for each series, one of the following actions was performed by the Originator:

• The data were declared good quality and no corrections were applied.
• Series with consistent offsets, spikes or periods of bad data were edited to correct for these issues. Spikes and periods of unrealistic values were converted to absent data indicators.
• The series was marked as 'use with caution', if there were problems which the Originator was unable to correct, or if it was unclear whether there was a problem with the data, such as in instances where it was not possible to perform all of the quality checks.
• If the quality of the data from a series was extremely poor, then the Originator recommended that the data should not be used.

A full description of the results of these quality checks can be found in the relevant Originator's data processing comments document.

Processing of Coastal Observatory Sea-Bird MicroCAT data by BODC

The data were provided to BODC in ASCII format, and the series were reformatted into BODC standard internal format using a transfer function. The following table shows how the Originator's variables present in the Sea-Bird MicroCAT data were mapped to the appropriate BODC parameter codes.

The reformatted data were visualised using the in-house EDSERPLO software. Suspect data were marked by adding an appropriate quality control flag, missing data by both setting the data to an appropriate value and setting the quality control flag. Any channels which comprised entirely of absent data indicators were excluded from the final qxf.

References

Fofonoff, NP and Millard, RC. 1983. Algorithms for computations of fundamental properties of seawater. UNESCO Technical Papers in Marine Science, 44, p.53.

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 and Hilbre Island, 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:

• Proudman Oceanographic Laboratory
• British Oceanographic Data Centre
• UK Meteorological Office
• Centre for Environment, Fisheries and Aquaculture Science
• Environment Agency
• Liverpool University and Port Erin Marine Laboratory
• Bangor University School of Ocean Sciences
• National Oceanography Centre Southampton
• Department of Agriculture and Rural Development in Northern Ireland

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

Data Activity or Cruise Information

Data Activity

SmartBuoy deployment LB2_005/POLRIG 946

Deployment and recovery

This mooring was deployed in a collaboration between Cefas and the POL Liverpool Bay Coastal Observatory. The rig was deployed during RV Prince Madog cruise No. 41, 2005 (PD41_05). The rig was recovered in February 2006 during RV Prince Madog cruise No. 4, 2006 (PD04_06).

Rig Description

The SmartBuoy carried a suite of Cefas instruments mounted just below the surface, as well as instrumentation belonging to POL at 5 m. Further information is given in the table below. A trial CTD with turbidity sensor was also attached in a cage at 10 m below surface. However, no data were received for this series and no further information is available.

The single point mooring was composed mainly of 0.5 inch long link chain, marked by a 1.8 m diameter toroid and anchored with a half ton clump of scrap chain.

• Cefas - The Centre for Environment, Fisheries and Aquaculture Science, Lowestoft (UK)
• POL - The Proudman Oceanographic Laboratory, Liverpool (UK)

Related Data Activity activities are detailed in Appendix 1

Cruise

Complete Cruise Metadata Report is available here

Fixed Station Information

Fixed Station Information

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:

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

Mooring Deployment History

2010

2009

2008

2007

2006

2005

CTD Sampling History

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

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:

SeaDataNet Quality Control Flags

The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:

Appendix 1: LB2_005/946

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.

Appendix 2: Coastal Observatory Site 21

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.