Metadata Report for BODC Series Reference Number 953391
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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Spatial Co-ordinates | |||||||||||||||||||||||||||||
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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
Kongsberg Simrad EA500 bathymetric echosounder
The EA500 is a bathymetric echosounder that can be used in water as deep as 10,000 m. It features triple frequency operation with a separate digitiser for each channel and high transmitted power with an instantaneous dynamic range of 160 dB. The instrument can operate with several pulses in the water simultaneously and has bottom tracking capabilities. A wide range of transducers (single beam, split beam or side-looking) is available and the ping rate is adjustable up to 10 pings per second. The split beam operation measures the athwartships inclination angle of the seabed.
This instrument was introduced in June 1989 and and replaced by the EA 600 in 2000.
Specifications
Operational range | 1, 5, 10, 15, 25, 50, 100, 150, 250, 500, 750, 1000, 2500, 5000 and 10000 m |
Phasing | 0 to 10000 m in 1 m increments (manual or automatic) |
Non saturated instantaneous input range | -160 to 0 dB |
Output power regulation | 0 to 20 dB relative to full power |
Noise figure | 10 dB |
Operating temperature | 0 to 55°C |
Ping rate | max 10 pings per second (adjustable) |
Further details can be found in the manufacturer's specification sheet.
Decca Navigator System
The Decca Navigator System (DNS) was a hyperbolic radio navigation system that operated by measuring the phase differences between continuous signals from master and slave stations. The differences were then related to hyperbolic lines printed on a chart (also known as lines of lattice). By plotting the readings from two pairs of hyperbolas at any particular instant, the user was able to plot their position instantly. The system operated from WWII until the UK transmitters were switched off at the end of March 2000.
The DNS consisted of groups of at least three shore based transmitter stations (or chains) which comprised one Master and two or three slave stations, usually located 80 to 110 km from the master station and positioned about 120° apart. The accuracy of this system depended on the distance to the baseline, time of day and seasonal effects.
The table below presents the general specifications for this system.
Specifications
Frequency | 70 - 130 kHz |
Accuracy | 50 m (daytime) 200 m (at night) |
Maximum Range | 300 - 400 nm (daytime) 240 nm (at night) |
Further details can be found here.
Project Information
North Sea Project
The North Sea Project (NSP) was the first Marine Sciences Community Research project of the Natural Environment Research Council (NERC). It evolved from a NERC review of shelf sea research, which identified the need for a concerted multidisciplinary study of circulation, transport and production.
The ultimate aim of the NERC North Sea Project was the development of a suite of prognostic water quality models to aid management of the North Sea. To progress towards water quality models, three intermediate objectives were pursued in parallel:
- Production of a 3-D transport model for any conservative passive constituent, incorporating improved representations of the necessary physics - hydrodynamics and dispersion;
- Identifying and quantifying non-conservative processes - sources and sinks determining the cycling and fate of individual constituents;
- Defining a complete seasonal cycle as a database for all the observational studies needed to formulate, drive and test models.
Proudman Oceanographic Laboratory hosted the project, which involved over 200 scientists and support staff from NERC and other Government funded laboratories, as well as seven universities and polytechnics.
The project ran from 1987 to 1992, with marine field data collection between April 1988 and October 1989. One shakedown (CH28) and fifteen survey cruises (Table 1), each lasting 12 days and following the same track, were repeated monthly. The track selected covered the summer-stratified waters of the north and the homogeneous waters in the Southern Bight in about equal lengths together with their separating frontal band from Flamborough head to Dogger Bank, the Friesian Islands and the German Bight. Mooring stations were maintained at six sites for the duration of the project.
Table 1: Details of NSP Survey Cruises on RRS Challenger | |
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Cruise No. | Date |
CH28 | 29/04/88 - 15/05/88 |
CH33 | 04/08/88 - 16/08/88 |
CH35 | 03/09/88 - 15/09/88 |
CH37 | 02/10/88 - 14/10/88 |
CH39 | 01/11/88 - 13/11/88 |
CH41 | 01/12/88 - 13/12/88 |
CH43 | 30/12/88 - 12/01/89 |
CH45 | 28/01/89 - 10/02/89 |
CH47 | 27/02/89 - 12/03/89 |
CH49 | 29/03/89 - 10/04/89 |
CH51 | 27/04/89 - 09/05/89 |
CH53 | 26/05/89 - 07/06/89 |
CH55 | 24/06/89 - 07/07/89 |
CH57 | 24/07/89 - 06/08/89 |
CH59 | 23/08/89 - 04/09/89 |
CH61 | 21/09/89 - 03/10/89 |
Alternating with the survey cruises were process study cruises (Table 2), which investigated some particular aspect of the science of the North Sea. These included fronts (nearshore, circulation and mixing), sandwaves and sandbanks, plumes (Humber, Wash, Thames and Rhine), resuspension, air-sea exchange, primary productivity and blooms/chemistry.
Table 2: Details of NSP Process cruises on RRS Challenger | ||
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Cruise No. | Date | Process |
CH34 | 18/08/88 - 01/09/88 | Fronts - nearshore |
CH36 | 16/09/88 - 30/09/88 | Fronts - mixing |
CH56 | 08/07/89 - 22/07/89 | Fronts - circulation |
CH58 | 07/08/89 - 21/08/89 | Fronts - mixing |
CH38 | 24/10/88 - 31/10/88 | Sandwaves |
CH40 | 15/11/88 - 29/11/88 | Sandbanks |
CH42 | 15/12/88 - 29/12/88 | Plumes/Sandbanks |
CH46 | 12/02/89 - 26/02/89 | Plumes/Sandwaves |
CH44 | 13/01/89 - 27/01/89 | Resuspension |
CH52 | 11/05/89 - 24/05/89 | Resuspension |
CH60 | 06/09/89 - 19/09/89 | Resuspension |
CH48 | 13/03/89 - 27/03/89 | Air/sea exchanges |
CH62 | 05/10/89 - 19/10/89 | Air/sea exchanges |
CH50 | 12/04/89 - 25/04/89 | Blooms/chemistry |
CH54 | 09/06/89 - 22/06/89 | Production |
In addition to the main data collection period, a series of cruises took place between October 1989 and October 1990 that followed up work done on previous cruises (Table 3). Process studies relating to blooms, plumes (Humber, Wash and Rhine), sandwaves and the flux of contaminants through the Dover Strait were carried out as well as two `survey' cruises.
Table 3: Details of NSP `Follow up' cruises on RRS Challenger | ||
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Cruise No. | Date | Process |
CH62A | 23/10/89 - 03/11/89 | Blooms |
CH64 | 03/04/90 - 03/05/90 | Blooms |
CH65 | 06/05/90 - 17/05/90 | Humber plume |
CH66A | 20/05/90 - 31/05/90 | Survey |
CH66B | 03/06/90 - 18/06/90 | Contaminants through Dover Strait |
CH69 | 26/07/90 - 07/08/90 | Resuspension/Plumes |
CH72A | 20/09/90 - 02/10/90 | Survey |
CH72B | 04/10/90 - 06/10/90 | Sandwaves/STABLE |
CH72C | 06/10/90 - 19/10/90 | Rhine plume |
The data collected during the observational phase of the North Sea Project comprised one of the most detailed sets of observations ever undertaken in any shallow shelf sea at that time.
Data Activity or Cruise Information
Cruise
Cruise Name | CH72C |
Departure Date | 1990-10-06 |
Arrival Date | 1990-10-19 |
Principal Scientist(s) | John H Simpson (University of Wales, Bangor School of Ocean Sciences) |
Ship | RRS Challenger |
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 |
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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 |