Metadata Report for BODC Series Reference Number 2099571

• 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

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

Turner Designs 700 (TD-700) Laboratory Fluorometer

The TD-700 Laboratory Fluorometer is a benchtop fluorometer that is designed to detect fluorescence over the UV to red range. It uses a Quartz Halogen Lamp or a Low Pressure Mercury Vapour Lamp to excite the species of interest and fluorescence is detected by a photomultiplier tube with a detection range of 300-650 nm. A red-sensitive tube with a detection range of 185-870 nm is also available. The instrument can measure concentrations of a variety of compounds, including chlorophyll-a and fluorescent dyes, and is thus suitable for a range of applications, including chlorophyll, water quality monitoring and fluorescent tracer studies.

The fluorometer uses a filter cylinder that accommodates up to eight, 1 inch round filters; four filters for excitation and four emission filters. The sample compartment can accommodate a wide range of sample volumes and an additional Helix Microcell accessory can be added for small sample volumes where three to nine µl of assay solution will be used. Application-specific optical kits can be combined with the TD-700 to determine the fluorescence of a variety of compounds.

Samples can be averaged to improve accuracy, and the instrument can read and subtract a blank measurement from the data, further improving the accuracy. Calibration of the fluorometer can either be multi-point for data output as concentrations or single-point for data output as raw fluorescence measurements. The TD-700 has now been replaced with the Trilogy Laboratory Fluorometer.

Specifications

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

Non-toxic (underway) sea water supply

A source of uncontaminated near-surface (commonly 3 to 7 m) seawater pumped continuously to shipboard laboratories on research vessels. There is typically a temperature sensor near the intake (known as the hull temperature) to provide measurements that are as close as possible to the ambient water temperature. The flow from the supply is typically directed through continuously logged sensors such as a thermosalinograph and a fluorometer. Water samples are often collected from the non-toxic supply. The system is also referred to as the underway supply.

JC086 discrete chlorophyll a sampling document

Originator's protocol for data acquisition and analysis

The following information contains extracts from the JC086 cruise report.

Water samples were drawn from the CTD rosette bottles deployed during the cruise at 5 m depth, chlorophyll maxima, 50 m, 75 m and 100 m. 23 samples were also drawn from the ships non-toxic water supply.

Samples were collected from the CTD in 2 L polythene bottles and between 1 and 2 litres of each sample were filtered through Whatman 25 mm GF/F diameter glass fibre filters. Normally 1 L of the sample was filtered if collected from the chlorophyll maxima, and 2 L filtered from samples taken below this depth. A maximum of five depths were sampled from 54 casts along the transect.

Samples, once collected and filtered, were stored in plastic 15 mm diameter centrifuge tubes in a -20 ^oC freezer. Extraction of 5 ml of 90% buffered acetone was then injected into each tube and the sample sonicated for one minute. Finally, an aliquot of the extract was taken and measured on a Turner bench top fluorometer using a chlorophyll calibrated program.

BODC data processing procedures

The chlorophyll data were supplied to BODC in an MSTAR format. This data were converted to Microsoft Excel format and data were loaded into BODC's ocean database under the ORACLE Relational Database Management System without modification. Data that were considered unrealistic were flagged suspect. Metadata collected from the various data files were favoured by BODC over the metadata recorded in the cruise report logs in the JC086 cruise report.

Content of data series

Data quality report

No problems reported and no significant issues encountered during BODC data banking procedures.

References cited

Griffiths C. R. et al., (2013). RRS James Cook Cruise JC086, 06 May 2013 - 26 May 2013. Govan to Govan, Scotland - the Extended Ellett Line. Scottish Association for Marine Science. (Scottish Marine Institute, Oban).

Available - Cruise JC086 Internal Report

Project Information

Oceans 2025 Theme 10, Sustained Observation Activity 4: The Extended Ellett Line

The Ellett Line (begun in 1975 and since 1996 the Extended Ellett Line from Scotland to Iceland) crosses important north Atlantic Meridional Overturning Circulation (MOC) components and thus provides an additional contribution to understanding the north Atlantic response to climate change. Sustained Observation Activity (SO) 4 will repeat this section annually collecting a wide variety of physical and biogeochemical measurements, and will, to enhance the time variable component, make use of Argo floats and gliders. SO 4 will be implemented by physical, biological and chemical scientists at the National Oceanography Centre, Southampton (NOCS) and the Scottish Association for Marine Science (SAMS).

SO 4 formally contributes to the Department for Environment, Food and Rural Affairs (DEFRA)-funded Marine Environmental Change Network (MECN). Established in 2002 to coordinate and promote the collection and utilisation of marine time-series and long-term data sets, the goal of the network is to use long-term marine environmental data from around the British Isles and Ireland to separate natural fluctuations from global, regional and local anthropogenic impacts.

The specific deliverables for SO 4 are:

• A time series of the evolution of the hydrography of the northeast Atlantic, together with a more formal understanding of the causes of any changes observed
• An archived data set available to the international community via the British Oceanographic Data Centre (BODC)
• A platform for further scientific research

More detailed information on this Work Package is available at pages 15 - 16 of the official Oceans 2025 Theme 10 document: Oceans 2025 Theme 10

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

Data Activity or Cruise Information

Cruise

Complete Cruise Metadata Report is available here

Fixed Station Information

No Fixed Station Information held for the Series

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: