Metadata Report for BODC Series Reference Number 911843
No Problem Report Found in the Database
Data Quality Document
Temperature, salinity and sigma-theta:
The profiles appear good. Only a few large isolated spikes were flagged as suspect by BODC. Users should be aware that a number of casts from these series displayed stronger variability in the suface layer.
The profile trends match well with the transmissometer trends (high fluorometer voltages corresponding to low transmission). Since this is a voltage there are no comments on the absolute values. There is natural variability in the profile but nothing considered suspect that required flagging.
The profile trends match well with the fluorometer voltage trends (high fluorometer voltages corresponding to low transmission). Values do not exceed 100%. There is natural variability in the profile but nothing considered suspect that required flagging.
Downwelling PAR irradiance:
The trend is consistent with what would be expected for each profile. Noise in the surface bins can be due to changing cloud cover. There is natural variability in the profiles but nothing considered suspect that required flagging.
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."
These data are collected using a CTD rig on the R/V Plymouth Quest. The CTD frame houses the following instruments:
|Chelsea Technologies||PAR sensor||07-6346-001|
|Chelsea Technologies||MiniTracka II||07-6310-003|
|WetLabs||C-Star (red) 25cm path length||CST-1038PR|
Sea-Bird SBE 19 and SBE 19plus SEACAT Profiler CTDs
The SBE 19 SEACAT Profiler is a self-contained, battery powered, pumped CTD system designed to measure conductivity, temperature, and pressure in marine or fresh water environments to depths of 10,500 meters. It was replaced by the SBE 19plus model in 2001. An updated version of this instrument is the SBE 19plus V2, which incorporates an electronics upgrade and additional features, with six differentially amplified A/D input channels, one RS-232 data input channel, and 64 MB FLASH memory.
The standard CTD unit comes with a plastic housing (rated to 600 m), although this can be replaced by titanium housing for depths up to 7000 m. It is typically used for CTD profiling although a conversion kit is available for mooring deployments. The CTD can also be attached to an SBE 36 CTD Deck Unit and Power/Data Interface Module (PDIM) for real-time operation on single-core armored cable up to 10,000 m.
|Parameter||SBE 19||SBE 19plus|
Range: -5 to +35 °C
Accuracy: 0.01 °C
Resolution: 0.001 °C
Calibration: +1 to +32 °C*
Range: -5 to +35 °C
Accuracy: 0.005 °C
Resolution: 0.0001 °C
Calibration: +1 to +32 °C*
Range: 0 to 7 S m-1 (0 to 70 mmho cm-1)
Accuracy: 0.001 S m-1
Resolution: 0.0001 S m-1
Calibration: 0 to 7 S m-1. Physical calibration over the range 1.4 - 6 S m-1*
Range: 0 to 9 Sm-1
Resolution: 0.00005 (most oceanic waters, resolves 0.4 ppm in salinity); 0.00007 (high salinity waters, resolves 0.4 ppm in salinity); 0.00001 (fresh waters, resolves 0.1 ppm in salinity)
Calibration: 0 to 9 S m-1. Physical calibration over the range 1.4 - 6 S m-1*
|Strain gauge pressure sensor|| |
Range: 0 to100, 150, 300, 500, 1000, 1500, 3000, 5000, 10000 or 15000 psia
Accuracy: 0.25% of full scale range (100 - 1500 psia); 0.15% of full scale range (3000 - 15000 psia)
Resolution: 0.015% of full scale
Calibration: 0 to full scale in 20% steps
Range: 0 to 20, 100, 350, 1000, 2000, 3500 or 7000 m
Accuracy: 0.1% of full scale range
Resolution: 0.002% of full scale range
Calibration: ambient pressure to full scale range in 5 steps
*Measurements outside this range may be at slightly reduced accuracy due to extrapolation errors.
Options and accessories
Additional sensors can be attached to the CTD, including:
- high accuracy Paroscientific Digiquartz pressure sensor (depth range 0 to 20, 60, 130, 200, 270, 680, 1400, 2000, 4200, 7000 or 10500 m; accuracy 0.02% of full scale; resolution 0.0025% of full scale)
- Dissolved Oxygen (SBE 43 DO Sensor)
- pH* (SBE 18 pH Sensor or SBE 27 pH/ORP Sensor)
- radiance (PAR)
- light transmission
- optical backscatter (turbidity)
The standard SBE 5M pump may be replaced by an SBE 5P (plastic housing) or 5T (titanium housing) pump for use with dissolved oxygen and/or other pumped sensors. Further details can be found in the manufacturer's SBE 19plus V2 instrument specification or theSBE 19 andSBE 19 plus user guides.
Chelsea Instruments MINItracka Fluorometer
The MINItracka Fluorometer is an in-situ optical sensor that uses a single high intensity LED light source and, according to the manufacturer, is designed to enhance rejection of ambient daylight. The fluorometer provides a linear response between chlorophyll concentration and fluorometer voltage.
Sensor specifications, current at August 2006, are given in the table below. More information can be found at the manufacturer's specification sheet.
|Excitation wavelengths||430/30 nm||470/30 nm||470/30 nm||425/30 nm||480/80 nm|
|Emission wavelength||685/30 nm||685/30 nm||590/45 nm||550/30 nm||530/30 nm|
|Concentration range||0.03-100 µg l-1||0.03-100 µg l-1||0.03-100 µg l-1||0.04-200 µg l-1||0.03-100 µg l-1|
|Resolution||0.01 µg l-1||0.01 µg l-1||0.01 µg l-1||0.025 µg l-1||0.01 µg l-1|
|Calibration standard||Chlorophyll-a in acetone||Chlorophyll-a in acetone|
|Excitation wavelengths||470/30 nm||530/30 nm||590/35nm|
|Emission wavelength||470/30 nm||580/30 nm||645/35 nm|
|Concentration range||0.04-100 FTU||0.03-100 µg l-1||0.03-100 µg l-1|
|Resolution||0.01 FTU||0.01 µg l-1||0.01 µg l-1|
|Body Size||149 mm long x 70 mm dia||Input Voltage||7 to 40 VDC|
|Weight in Air||0.7 Kg||Output Voltage||0 to 4 VDC (linear)|
|Weight in Water||0.15 Kg||Power requirements||0.7 W typical|
|Depth Rating||600 m||Signal : Noise||10,000 : 1 @ full scale|
Chelsea Technologies Photosynthetically Active Radiation (PAR) Irradiance Sensor
This sensor was originally designed to assist the study of marine photosynthesis. With the use of logarithmic amplication, the sensor covers a range of 6 orders of magnitude, which avoids setting up the sensor range for the expected signal level for different ambient conditions.
The sensor consists of a hollow PTFE 2-pi collector supported by a clear acetal dome diverting light to a filter and photodiode from which a cosine response is obtained. The sensor can be used in moorings, profiling or deployed in towed vehicles and can measure both upwelling and downwelling light.
|Operation depth||1000 m|
|Range||2000 to 0.002 µE m-2 s-1|
|Angular Detection Range||± 130° from normal incidence|
|Relative Spectral Sensitivity|| |
flat to ± 3% from 450 to 700 nm
down 8% of 400 nm and 36% at 350 nm
Further details can be found in the manufacturer's specification sheet.
WETLabs C-Star transmissometer
This instrument is designed to measure beam transmittance by submersion or with an optional flow tube for pumped applications. It can be used in profiles, moorings or as part of an underway system.
Two models are available, a 25 cm pathlength, which can be built in aluminum or co-polymer, and a 10 cm pathlength with a plastic housing. Both have an analog output, but a digital model is also available.
This instrument has been updated to provide a high resolution RS232 data output, while maintaining the same design and characteristics.
|Pathlength||10 or 25 cm|
|Wavelength||370, 470, 530 or 660 nm|
~ 20 nm for wavelengths of 470, 530 and 660 nm
~ 10 to 12 nm for a wavelength of 370 nm
|Temperature error||0.02 % full scale °C-1|
|Temperature range||0 to 30°C|
|Rated depth|| |
600 m (plastic housing)
6000 m (aluminum housing)
Originator's Sampling Strategy
These data were collected using a CTD rig deployed from PML research vessels.
The raw CTD data were processed using the Sea-Bird software and binned to 0.25 m. The data were provided in tab delimited format.
BODC post-processing and screening
The data were converted from tab delimited format into BODC internal format using BODC transfer function 401. During transfer the depth variable was converted to pressure using the routine 'sw_pres', a part of the Seawater toolbox, this used the method of Fofonoff and Millard Jr. (1983) using inputs of depth and latitude. The density parameter was not transferred by BODC as this is generated to a standard algorithm during BODC transfer.
The measured variables were mapped to BODC parameter codes shown in the table below:
|Originator's Parameter Name||Units||Description||BODC parameter code||Units||Comments|
|Temp||Deg C||Temperature of the water column||TEMPST01||Deg C||-|
|Fluor||volts||Raw fluorometer voltage||FVLTZZ01||volts||-|
|Depth||m||Depth of the water column||DEPHPR01||m||-|
|Density||kg m-3||Density of the water column by unknown algorithm||-||-||Channel not transferred as generated during BODC transfer|
|Sal||-||Salinity of the water column||PSALST01||-||-|
|PAR||µE m-2s-1||Downwelling PAR irradiance||IRRDPP01||µE m-2s-1||-|
|-||-||Pressure||PRESPR01||dbar||Calculated by BODC from depth and latitude|
|-||-||Sigma-theta||SIGTPR01||kg m-3||Generated by BODC using Fofonoff and Millard (1983) algorithm with parameters PRESPR01, TEMPST01 and PSALST01.|
Reformatted CTD data were transferred onto a graphics work station for visualisation using the in-house editor EDSERPLO. No data values were edited or deleted. Flagging was achieved by modification of the associated BODC quality control flag for suspect or null values.
The profiles were banked to the National Oceanographic Database (NODB) following BODC procedures.
Fofonoff, N.P. and Millard, R.C., 1983. Algorithms for computations of fundamental properties of seawater. UNESCO Technical Papers in Marine Science No. 44, 53pp.
Oceans 2025 Theme 10, Sustained Observation Activity 10: The Western Channel Observatory (WCO)
The Western Channel Observatory will study the regional effects of ecosystem variability in the Western English Channel, in the context of global climate change. There is a long history of in situ observation at several sites (by the MBA for over 100 years and PML since the 1980s) that have been brought together to form the basis of the Western Channel Observatory; these observations include hydrography, nutrients, phytoplankton, zooplankton, demersal and pelagic fish and benthic measurements. It is upon these long-term time series that the WCO aims to continue building in order to investigate the current state of the ecosystem, how the ecosystem has changed and how the interactions of climate and fishing affect the ecosystem? The WCO provides an opportunity to combine modelling and Earth Observation infrastructure along with in situ data collection to demonstrate and validate short term forecasts of coastal phytoplankton and nutrient dynamics, as well as develop, calibrate and validate Earth Observation algorithms for bio-optical data.
The specific objectives are:
- To continue WCO operation (weekly sampling at L4 and fortnightly sampling at E1 sites)
- To provide a web enabled database of all in situ measurements and develop a web-GIS based data delivery system
- To make the backlog of historical data in digital format available to Theme 6
- To provide web enabled database of all Earth Observation data and delivery of model forecasts
- Incorporate time series into national and European networks
The work of the observatory will link to other parts of Theme 10 through the Continuous Plankton Recorder (CPR) routes that cover the Western English Channel (SO15) and by relevant ship-of-opportunity transects (SO8).
More detailed information on this Work Package is available at pages 28 - 31 of the official Oceans 2025 Theme 10 document: Oceans 2025 Theme 10
|Principal Scientist(s)||Tim Smyth (Plymouth Marine Laboratory)|
|Ship||RV Plymouth Quest|
Complete Cruise Metadata Report is available here
Fixed Station Information
|Station Name||Western Channel Observatory E1|
|Latitude||50° 2.00' N|
|Longitude||4° 22.00' W|
|Water depth below MSL||75.0 m|
Western Channel Observatory station E1
The Western Channel Observatory (WCO) is situated in the Western English Channel and comprises of sustained long-term observations at a number of stations.
Station E1 is located south-west of Plymouth at 50° 2.00' N, 4° 22.00' W.
More information can be found on the Western Channel Observatory website.
Other Cruises linked to this Fixed Station (with the number of series) - D366 (D367) (2) MS070911 (1) MS071101 (1) PML020626 (1) PML020717 (1) PML020814 (1) PML021002 (1) PML021031 (1) PML021213 (1) PML030124 (1) PML030213 (1) PML030321 (1) PML030423 (1) PML030514 (1) PML030604 (1) PML030611 (1) PML030618 (1) PML030625 (1) PML030702 (1) PML030709 (1) PML030806 (1) PML030909 (1) PML040803 (1) PML040826 (1) PML041102 (1) PML041208 (1) PML050202 (1) PML050308 (1) PML050330 (1) PML050511 (1) PML050608 (1) PML050620 (1) PML050713 (1) PML050810 (1) PML050831 (1) PML050914 (1) PML050928 (1) PML051118 (1) PML060118 (1) PML060208 (1) PML060301 (1) PML060315 (1) PML061010 (1) PML061101 (1) PML070206 (1) PML070313 (1) PQ070417 (1) PQ070501 (1) PQ070605 (1) PQ070703 (1) PQ070731 (1) PQ080415 (1) PQ080429 (1) PQ080513 (1) PQ080520 (1) PQ080603 (1) PQ080617 (1) PQ080715 (1) PQ080822 (1) PQ080916 (1) PQ081008 (1) PQ081022 (1) PQ081104 (1) PQ081211 (1) PQ090107 (1) PQ090127 (1) PQ090211 (1) PQ090226 (1) PQ090311 (1) PQ090401 (1) PQ090415 (1) PQ090528 (1) PQ090609 (1) PQ090623 (1) PQ090921 (1) PQ090930 (1) PQ091013 (1) PQ100127 (1) PQ100317 (1) PQ100428 (1) PQ100511 (1) PQ100617 (1) PQ100628 (1) PQ100720 (1) PQ100817 (1) PQ100901 (1) PQ100921 (1) PQ101014 (1) PQ101115 (1) PQ101214 (1) PQ110118 (1) PQ110308 (1) PQ110321 (1) PQ110407 (1) PQ110419 (1) PQ110517 (1) PQ110602 (1) PQ110628 (1) PQ110714 (1) PQ110809 (1) PQ110823 (1) PQ110922 (1) PQ111028 (1) PQ111107 (1) PQ111122 (1) PQ120113 (1) PQ120123 (1) PQ120228 (1) PQ120314 (1) PQ120427 (1) PQ120516 (1) PQ120612 (1) PQ120626 (1) PQ120710 (1) PQ120724 (1) PQ120808 (1) PQ120823 (1) PQ120904 (1) PQ120919 (1) PQ121009 (1) PQ121023 (1) PQ121106 (1) PQ121129 (1) PQ121211 (1) SQ020516 (1)
The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:
|<||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.)|
|E||End of CTD Down/Up Cast|
|G||Non-taxonomic biological characteristic uncertainty|
|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|
|O||Improbable value - user quality control|