Metadata Report for BODC Series Reference Number 1222947
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
RRS Bransfield Cruise AMT6B Underway Navigation and Surface Hydrography Data Quality Report
The range of parameters were limited in scope compared to other AMT cruises.
Due to very little documentation and metadata available care should be taken when making assumptions about the data from this cruise.
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
WET Labs WETStar Fluorometers
WET Labs WETStar fluorometers are miniature flow-through fluorometers, designed to measure relative concentrations of chlorophyll, CDOM, uranine, rhodamineWT dye, or phycoerythrin pigment in a sample of water. The sample is pumped through a quartz tube, and excited by a light source tuned to the fluorescence characteristics of the object substance. A photodiode detector measures the portion of the excitation energy that is emitted as fluorescence.
Specifications
By model:
| Chlorophyll WETStar | CDOM WETStar | Uranine WETStar | Rhodamine WETStar | Phycoerythrin WETStar | |
|---|---|---|---|---|---|
| Excitation wavelength | 460 nm | 370 nm | 485 nm | 470 nm | 525 nm |
| Emission wavelength | 695 nm | 460 nm | 530 nm | 590 nm | 575 nm |
| Sensitivity | 0.03 µg l-1 | 0.100 ppb QSD | 1 µg l-1 | - | - |
| Range | 0.03-75 µg l-1 | 0-100 ppb; 0-250 ppb | 0-4000 µg l-1 | - | - |
All models:
| Temperature range | 0-30°C |
|---|---|
| Depth rating | 600 m |
| Response time | 0.17 s analogue; 0.125 s digital |
| Output | 0-5 VDC analogue; 0-4095 counts digital |
Further details can be found in the manufacturer's specification sheet, and in the instrument manual.
Global Positioning Satellite System
A location system of unspecified make or model that determines location on the Earth's surface using the Global Positioning Satellite Network. Angular co-ordinates are given relative to WGS84 CRS. Other parameters such as platform velocity may be derived from this.
SeaTech Transmissometer
Introduction
The transmissometer is designed to accurately measure the the amount of light transmitted by a modulated Light Emitting Diode (LED) through a fixed-length in-situ water column to a synchronous detector.
Specifications
- Water path length: 5 cm (for use in turbid waters) to 1 m (for use in clear ocean waters).
- Beam diameter: 15 mm
- Transmitted beam collimation: <3 milliradians
- Receiver acceptance angle (in water): <18 milliradians
- Light source wavelength: usually (but not exclusively) 660 nm (red light)
Notes
The instrument can be interfaced to Aanderaa RCM7 current meters. This is achieved by fitting the transmissometer in a slot cut into a customized RCM4-type vane.
A red LED (660 nm) is used for general applications looking at water column sediment load. However, green or blue LEDs can be fitted for specilised optics applications. The light source used is identified by the BODC parameter code.
Further details can be found in the manufacturer's Manual.
RRS Bransfield Cruise AMT6B Underway Navigation and Surface Hydrography InstrumentationDocument
Instrumentation
Details of the ship's instrumentation were not provided.
After consulting a senior data scientist the following instrumentation was proposed using knowledge and experience of the instrumentation at that time. It is thought the instruments may have been from an RVS underway board, which carried a SeaTech 20cm transmissometer, an SBE-21 and a WetLabs fluorometer. It is not known what instrument measured the position of the ship.
The table below gives a best case scenario based upon the information available:
| Instrument name | Model | Serial Number | Parameter(s) |
|---|---|---|---|
| GPS | N/A | N/A | ALATZZ01 and ALONZZ01 |
| Sea-Bird SBE 21 Thermosalinograph | SBE 21 | N/A | PSALSU01 and TEMPSU01 |
| WETLabs fluorometer | Unknown | N/A | CPHLUMTF |
| SeaTech 20 cm Transmissometer | Unknown | N/A | TVLTZR01 |
Extreme caution should be taken when making assumptions based on the instrumentation for this cruise.
RRS Bransfield Cruise AMT6B Underway Navigation and Surface Hydrography Processing Document
Originator's Data Processing
Details of of onboard data acquisition and processing were not provided.
BODC Data Processing
Reformatting
The underway data file was transferred to a binary file for screening at BODC. The time span of the file was from 05/04/1998 18:59 to 03/05/1998 14:09, with a sampling interval of 10 minutes.
Screening
Each data channel was inspected on a graphics workstation and any spikes or periods of dubious data were flagged. The power of the workstation software was used to carry out comparative screening checks between channels by overlaying data channels. A map of the cruise track was simultaneously displayed in order to take account of the oceanographic context.
Data processing, correction and calibration
Navigation
A program was run which located any null values in the latitude and longitude channels and checked to ensure that the ship's speed did not exceed 15 knots. The program identified 3 gaps which were filled using linear interpolation.
Sample Calibrations
No CTD sampling was carried out on this cruise and limited data were returned to BODC. No calibrations or corrections have been applied to the data.
References
Fofonoff, N.P. and Millard Jr., R.C., 1982. Algorithms for Computation of Fundamental Properties of Seawater. UNESCO Technical Papers in Marine Science, 44.
SeaBird 21 SeaCAT Thermosalinograph SBE 21
The SBE21 is an externally powered instrument used to determine sea surface temperature and conductivity from underway vessels. Data is simultaneously stored in memory and output to a computer in real-time. Typically mounted on the ship's seawater intake, the SBE21 connects to an AC-powered interface box near a computer. TH interface box provides power and an isolated data interface, and contains a NMEA 0183 port for appending navigation data. There are options for auxiliary sensors using the RS-232 interface for a SBE32 temperature sensor and for four single-ended or two differential 0-5 volt A/D input channels for voltage output auxiliary sensors.
Components include internal-field conductivity cell eliminates proximity effects, which also permits use of expendable anti-foulant devices, for long-term bio-fouling protection. The thermistor is aged and pressure-protected.
Specifications
| Conductivity | Temperature, primary | Temperature, SBE38 remote | |
|---|---|---|---|
| Range | 0 to 7 S/m | -5 to 35°C | -5 to 35°C |
| Initial Accuracy | ±0.001 S/m | ±0.01°C | ±0.001°C |
| Resolution | 0.000 S/m | 0.001°C | 0.0003°C |
More information may be found in the SBE21 brochure.
Project Information
The Atlantic Meridional Transect (AMT) - Phase 1 (1995-2000)
Who was involved in the project?
The Atlantic Meridional Transect (AMT) programme was designed by and implemented as a collaboration between Plymouth Marine Laboratory (PML) and Southampton Oceanography Centre (SOC). The programme was hosted by Plymouth Marine Laboratory and involved additional researchers from UK and international universities throughout its duration.
What was the project about?
When AMT began in 1995 the programme provided a platform for international scientific collaboration, including the calibration and validation of SeaWiFs measurements and products. The programme provided an exceptional opportunity for nationally and internationally driven collaborative research and provided a platform for excellent multi-disciplinary oceanographic research. As an in situ observation system, the data collected by the AMT consortium informed on changes in biodiversity and function of the Atlantic ecosystem during this period of rapid change to our climate and biosphere.
The scientific aims were to assess:
- mesoscale to basin scale phytoplankton processes
- the functional interpretation of bio-optical signatures
- the seasonal, regional and latitudinal variations in mesozooplankton dynamics
When was the project active?
The first phase of the AMT programme ran from 1995 to 2000 and consisted of a total of 12 cruises. A second phase of funding allowed the project to continue for the period 2002 to 2006 with a further 6 cruises.
Brief summary of the project fieldwork/data
The AMT programme undertook biological, chemical and physical oceanographic research during the annual return passage of the RRS James Clark Ross between the UK and the Falkland Islands or the RRS Discovery between the UK and Cape Town, a distance of up to 13,500 km. This transect crossed a range of ecosystems from sub-polar to tropical and from euphotic shelf seas and upwelling systems to oligotrophic mid-ocean gyres. The transect route was covered north-south in September/October and south-north in April/May of each year.
The measurements of hydrographic and bio-optical properties, plankton community structure and primary production completed on the first 12 transects (1995-2000) represent the most coherent set of repeated biogeochemical observations over ocean basin scales. This unique dataset has led to several important discoveries concerning the identification of oceanic provinces, validation of ocean colour algorithms, distributions of picoplankton, identifying new regional sinks of pCO2 and variability in rates of primary production and respiration.
Who funded the project?
The programme was funded by the Natural Environment Research Council (NERC) and further support was received from the National Aeronautics and Space Administration (NASA) with equipment and funding from the Sea-viewing Wild Field-of-view Sensor (SeaWiFS) project.
Data Activity or Cruise Information
Cruise
| Cruise Name | AMT6b |
| Departure Date | 1998-04-05 |
| Arrival Date | 1998-05-04 |
| Principal Scientist(s) | Gerald Moore (Plymouth Marine Laboratory) |
| Ship | RRS Bransfield |
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 |
