Metadata Report for BODC Series Reference Number 1868626
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 chlorophyll-a samples from CTD bottles and underway supply during RRS James Clark Ross JR20141115 (JR304)
Originator's Protocol for Data Acquisition and Analysis
Sampling protocol
Water samples for chlorophyll-a were taken from the ship's uncontaminated underway supply (intake at 6.5 metres below sea level) every two hours during transit periods. The total number of underway chlorophyll-a samples delivered to BODC was 112.
At a number of stations, CTD samples were taken from the upper 1000m of the water column for measurement of chlorophyll-a. A total of 103 chlorophyll-a samples were collected from 10 CTD casts.
Sampling Analysis
Each 300 ml sample was filtered through a 0.8 µm pore size 25 mm diameter, MPF300 filter, rinsed with milliQ water, placed in an eppendorf tube and stored at -20°C to be analysed at a later date. For the analysis the samples were extracted in 90% acetone for 22 to 24 hours at 4°C and measured on a Trilogy Turner Designs 7200 lab fluorometer, which had been calibrated using a pure chlorophyll-a standard (supplied by Sigma, UK) and set up using the Welschmeyer (1994) method. The data have not been adjusted for blanks.
References Cited
Welschmeyer N.A., 1994. Fluorometric analysis of chlorophyll-a in the presence of chlorophyll b and phaeopigments. Limnol Oceanogr, 39, 1985-1992.
BODC Data Processing Procedures
Data were received in one excel spreadsheet with accompanying metadata: Cruise name, Station, Type, Date, Time, Latitude, Longitude, Event, Niskin, Depth and Sample-ID. The CTD data was sent with accompanying Sea Surface temperature data, however these were not loaded as this information was obtained from the bottle files created when they are fired.
Metadata were used to match the sampling events with records in the database.
Data were loaded into the BODC database using established BODC data banking procedures without any changes. The originator's parameters were mapped to BODC parameter codes as follows:
| Originator's Parameter | Unit | Description | BODC Parameter Code | BODC Unit |
|---|---|---|---|---|
| Chlorophyll | mg m-3 | Concentration of chlorophyll-a {chl-a CAS 479-61-8} per unit volume of the water body [particulate >0.8um phase] by filtration, acetone extraction and fluorometry | CPHLFLP8 | mg m-3 |
Data Quality Report
One CTD sample was flagged as suspect by the originator, the corresponding L flag was assigned.
Project Information
BAS Long Term Monitoring and Survey
Introduction
The Long Term Monitoring and Survey project (LTMS) has been running since the British Antarctic Survey (BAS) was created. This project is one of the BAS core projects, with several groups of scientists collecting various types of data e.g biological, geological, atmospheric, among others.
Data collection is achievable through a wide scope of instruments and platforms, e.g. the Antarctic research stations, autonomous instrument platforms deployed on or from BAS research ships, BAS aircrafts, satellite remote sensing and others.
Scientific Objectives
This project was implemented in order to measure change and variability in the Earth system. Its long term duration allows for the monitoring of processes that could be missed in shorter term studies and experiments. The data collected is also used to check and improve the reliability of models used to stimulate and predict the behavior of the Earth system.
The main objectives are:
- Topographic survey
- Geosciences survey
- Biological survey and monitoring
- Atmospheric and oceanographic monitoring
Data Availability
The data sets obtained through this project are available to the academic community.
Data Activity or Cruise Information
Cruise
| Cruise Name | JR20141115 (JR304) |
| Departure Date | 2014-11-15 |
| Arrival Date | 2014-12-17 |
| Principal Scientist(s) | Jonathan L Watkins (British Antarctic Survey) |
| Ship | RRS James Clark Ross |
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 |
