Metadata Report for BODC Series Reference Number 1853615
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
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Time Co-ordinates(UT) |
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Parameters |
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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
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.
Discrete inorganic nutrient samples from underway non-toxic supply during RRS James Cook cruise 31 (JC031)
Originator's Protocol for Data Acquisition and Analysis
Discrete nutrient samples were collected from the non-toxic seawater supply (intake depth, approx. 5 m). Nutrient concentrations (silicate, phosphate and nitrate) were analysed using a segmented-flow nutrient autoanalyser with colourimetric detection (Skalar SANplus SYSTEM analyser (type 4000) fitted with a Skalar autosampler (type 1000)). More detailed information on the sampling and analysis of nutrient samples can be found from pages 44-50 of the cruise report.
BODC Data Processing Procedures
Data arrived at BODC in one Microsoft Excel format file. Data received were loaded into the BODC database using established BODC data banking procedures. The file contained measurements from experimental incubations, however, only nutrient measurements from the non-toxic supply were loaded. The data contained sample (not analytical) replicates (confirmed by the originator). These were averaged and all the data were screened in house prior to loading. The following discrepancies between the data originator's metadata and the metadata held centrally in the database were observed:
- Sampling IDs were converted to an appropriate BODC format.
- Times were not provided for two sampling events (UW_CTD15 and UW_CTD12) and we were unable to confirm them with the originator. However, the chlorophyll data, which was collected at the same time, had times associated with them. These times have been used for the nutrient data.
Originator's parameters were mapped with BODC codes as follows:
| Originator's variable | Originator's Units | Description | BODC code | BODC Units | Comments |
| Nitrate | µmol l-1 | Nitrate (nitrate+nitrite) | NTRZAATX | µmol l-1 | |
| Silicate | µmol l-1 | Silicate | SLCAAATX | µmol l-1 | |
| Phosphate | µmol l-1 | Phosphate | PHOSAATX | µmol l-1 |
Data Quality Report
The limits of detection and error between duplicate analytical replicates were determined by the originators. The limits of detection were defined as twice the level of background noise averaged out over the course of the cruise. The background noise levels in digital units (the arbitrary unit used by the Skalar autoanalyser software) were measured at the start and at the end of 10 of the 72 analyses. These were then averaged to give an averaged background noise level for the whole cruise. This number was then multiplied by 2. The concentration per digital unit was taken from the calculations used to determine the blank nutrient level in the artificial seawater matrix. Multiplying this number by the concentration per unit gives the limit of detection (Table 1).
Table 1. The limits of detection for the chemistries
| Chemistry | Limit of detection (µmol l-1) |
| Nitrate + nitrite | 0.15 |
| Silicate | 0.39 |
| Phosphate | 0.04 |
The percentage difference for the nutrient analysis were worked out using analytical duplicates run during each analysis. A drift sample was included in each analysis to indicate if the baseline moves over the course of the run. These drift samples are included in pairs, i.e. 2 drift samples from the same batch are run one after the other. The first pair of these drifts was used as the duplicate samples in each of the 72 analyses. The error for the each analysis was determined using the equation below. These errors were then averaged over the cruise to obtain the error for the whole cruise (Table 2).
100 * (A - B) * C, C = 2/(A + B)
Where A is the largest of the duplicates and B is the smallest.
Table 2. The errors associated with each of the chemistries
| Chemistry | Error in data (%) |
| Nitrate + nitrite | 0.69 |
| Silicate | 0.36 |
| Phosphate | 0.45 |
Problem Report
Times are approximate for UW_CTD15 and UW_CTD12. The samples were taken whilst on CTD station. The times associated to these samples are the nominal CTD station times and are not the exact time of sampling.(BODC assessment)
Project Information
Oceans 2025 - The NERC Marine Centres' Strategic Research Programme 2007-2012
Who funds the programme?
The Natural Environment Research Council (NERC) funds the Oceans 2025 programme, which was originally planned in the context of NERC's 2002-2007 strategy and later realigned to NERC's subsequent strategy (Next Generation Science for Planet Earth; NERC 2007).
Who is involved in the programme?
The Oceans 2025 programme was designed by and is to be implemented through seven leading UK marine centres. The marine centres work together in coordination and are also supported by cooperation and input from government bodies, universities and other partners. The seven marine centres are:
- National Oceanography Centre, Southampton (NOCS)
- Plymouth Marine Laboratory (PML)
- Marine Biological Association (MBA)
- Sir Alister Hardy Foundation for Marine Science (SAHFOS)
- Proudman Oceanographic Laboratory (POL)
- Scottish Association for Marine Science (SAMS)
- Sea Mammal Research Unit (SMRU)
Oceans2025 provides funding to three national marine facilities, which provide services to the wider UK marine community, in addition to the Oceans 2025 community. These facilities are:
- British Oceanographic Data Centre (BODC), hosted at POL
- Permanent Service for Mean Sea Level (PSMSL), hosted at POL
- Culture Collection of Algae and Protozoa (CCAP), hosted at SAMS
The NERC-run Strategic Ocean Funding Initiative (SOFI) provides additional support to the programme by funding additional research projects and studentships that closely complement the Oceans 2025 programme, primarily through universities.
What is the programme about?
Oceans 2025 sets out to address some key challenges that face the UK as a result of a changing marine environment. The research funded through the programme sets out to increase understanding of the size, nature and impacts of these changes, with the aim to:
- improve knowledge of how the seas behave, not just now but in the future;
- help assess what that might mean for the Earth system and for society;
- assist in developing sustainable solutions for the management of marine resources for future generations;
- enhance the research capabilities and facilities available for UK marine science.
In order to address these aims there are nine science themes supported by the Oceans 2025 programme:
- Climate, circulation and sea level (Theme 1)
- Marine biogeochemical cycles (Theme 2)
- Shelf and coastal processes (Theme 3)
- Biodiversity and ecosystem functioning (Theme 4)
- Continental margins and deep ocean (Theme 5)
- Sustainable marine resources (Theme 6)
- Technology development (Theme 8)
- Next generation ocean prediction (Theme 9)
- Integration of sustained observations in the marine environment (Theme 10)
In the original programme proposal there was a theme on health and human impacts (Theme 7). The elements of this Theme have subsequently been included in Themes 3 and 9.
When is the programme active?
The programme started in April 2007 with funding for 5 years.
Brief summary of the programme fieldwork/data
Programme fieldwork and data collection are to be achieved through:
- physical, biological and chemical parameters sampling throughout the North and South Atlantic during collaborative research cruises aboard NERC's research vessels RRS Discovery, RRS James Cook and RRS James Clark Ross;
- the Continuous Plankton Recorder being deployed by SAHFOS in the North Atlantic and North Pacific on 'ships of opportunity';
- physical parameters measured and relayed in near real-time by fixed moorings and ARGO floats;
- coastal and shelf sea observatory data (Liverpool Bay Coastal Observatory (LBCO) and Western Channel Observatory (WCO)) using the RV Prince Madog and RV Quest.
The data is to be fed into models for validation and future projections. Greater detail can be found in the Theme documents.
Data Activity or Cruise Information
Cruise
| Cruise Name | JC031 |
| Departure Date | 2009-02-03 |
| Arrival Date | 2009-03-03 |
| Principal Scientist(s) | Elaine McDonagh (National Oceanography Centre, Southampton) |
| Ship | RRS James Cook |
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:
| 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 |
| B | nominal value |
| Q | value below limit of quantification |
