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Metadata Report for BODC Series Reference Number 1103659


Metadata Summary

Data Description

Data Category Transmittance/attenuance, turbidity, or SPM conc.
Instrument Type
NameCategories
Sea-Bird SBE 19plus SEACAT CTD  CTD; water temperature sensor; salinity sensor
WET Labs {Sea-Bird WETLabs} ac-9 plus absorption and attenuation meter  transmissometers
Satlantic OCR-504 multispectral radiometer  radiometers
Instrument Mounting lowered unmanned submersible
Originating Country United Kingdom
Originator Dr Tim Smyth
Originating Organization Plymouth Marine Laboratory
Processing Status banked
Online delivery of data Download not available
Project(s) Oceans 2025 Theme 10 SO1:AMT
 

Data Identifiers

Originator's Identifier AMT19_OPT008_AC9_SUV_CTD_UNF_091018
BODC Series Reference 1103659
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 2009-10-18 13:45
End Time (yyyy-mm-dd hh:mm) 2009-10-18 14:06
Nominal Cycle Interval 2.0 metres
 

Spatial Co-ordinates

Latitude 43.22000 N ( 43° 13.2' N )
Longitude 21.18000 W ( 21° 10.8' W )
Positional Uncertainty 0.0 to 0.01 n.miles
Minimum Sensor or Sampling Depth 1.0 m
Maximum Sensor or Sampling Depth 185.0 m
Minimum Sensor or Sampling Height 4195.76 m
Maximum Sensor or Sampling Height 4379.76 m
Sea Floor Depth 4380.76 m
Sea Floor Depth Source GEBCO1901
Sensor or Sampling Distribution Variable common depth - All sensors are grouped effectively at the same depth, but this depth varies significantly during the series
Sensor or Sampling Depth Datum Instantaneous - Depth measured below water line or instantaneous water body surface
Sea Floor Depth Datum Chart reference - Depth extracted from available chart
 

Parameters

BODC CODERankUnitsTitle
LAMBIN010NanometresWavelength of electromagnetic radiation measurement
ACYCAA011DimensionlessSequence number
DEPHPR011MetresDepth (spatial coordinate) relative to water surface in the water body by profiling pressure sensor and conversion to seawater depth using UNESCO algorithm
PSALST011DimensionlessPractical salinity of the water body by CTD and computation using UNESCO 1983 algorithm
TEMPST011Degrees CelsiusTemperature of the water body by CTD or STD
ABSPXAC92per metreAbsorbance of electromagnetic radiation (unspecified single wavelength) {light absorbance} by the water body by transmissometer and calibration to read zero in clear water
ATTNXAC92per metreAttenuation (unspecified single wavelength) per unit length of the water body by transmissometer and calibration to read zero in clear water
DWIRXXED2Watts per square metre per nanometreDownwelling vector irradiance as energy of electromagnetic radiation (unspecified single wavelength) in the water body by cosine-collector radiometer

Definition of Rank

  • Rank 1 is a one-dimensional parameter
  • Rank 2 is a two-dimensional parameter
  • Rank 0 is a one-dimensional parameter describing the second dimension of a two-dimensional parameter (e.g. bin depths for moored ADCP data)

Problem Reports

No Problem Report Found in the Database

Data Quality Report for UV sensor and AC-9 profiles from cruise JC039

Data Quality Report

Absorbance

Absorbance profiles consistently have negative data values that are beyond the range of the parameter (0 - 250 per meter). These values have been flagged as suspect.

Flow rate

The flow rate channel was removed as the values were zero in all series.

Downwelling UV irradiance

Where values were out of the parameter range (0 - 100 W m-2 nm -1) they have been flagged as suspect, but the profile shapes appear reasonable.

Attenuance

Where values were out of the parameter range (0 - 400 per metre) they have been flagged as suspect, but the profile shapes appear reasonable.


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

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.

Specifications

Parameter SBE 19 SBE 19plus
Temperature

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*

Conductivity

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

Accuracy: 0.0005

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)
  • fluorescence
  • 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.

RRS James Cook Cruise AMT19 AC9 and UV Sensor profiles Instrumentation

Instrumentation Description

Instrument Serial Number Parameter
Satlantic 504-UV Sensor 168 Downwelling vector irradiance (305, 325, 340, 380 nm)
SeaBird SBE19+ CTD 19P27903-4180 Temperature, Salinity, depth, flow rate
Wetlabs ac9+ ac90277 Absorption / Attenuation at 412, 440, 488, 510, 532, 555, 650, 676, 715 nm

Satlantic OCR 500 series Multispectral Radiometer

The OCR-507 Multispectral Radiometer is a member of Satlantic's line of micro-sensor instruments. The OCR-507 is a complete stand-alone, fully digital optical sensor package capable of generating spectral records of light collected in an ocean environment. The instrument comprises data logging and processing software and is available in two configurations, radiance and irradiance for in-water and in-air applications. The instrument can also be configured as a coupled irradiance and radiance radiometer. Up to seven customer defined discrete optical wavelengths can be utilized with the OCR-507, including standard wavelengths of 400 to 865 nm, or UV wavelengths of 305, 325, 340 and 380 nm.

Two standard, non-isolated, telemetry (data) interfaces are provided with the instrument, each using a different transmission medium. The RS-232 interface provides transmit and receive capabilities whilst the RS-422 interface is for transmittance only. A non-isolated RS-485 interface is also provided for operating the instrument if used in a SatNet networked environment as part of a larger system.

The OCR-507 combines a fully characterized cosine response with custom low fluorescence filters and a sampling rate of 7 to 24 Hz. The instrument is also compatible with Bioshutter anti-biofouling solution.

Specifications for Downwelling Irradiance Configuration

  OCR-504 OCR-507
Field of view in-air or in-water cosine response (spectrally corrected) in-air or in-water cosine response (spectrally corrected)
Collector area 86 mm2 86 mm2
Detectors custom 17 mm2 silicon photodiodes custom 17 mm2 silicon photodiodes
Bandwidth range 400-865 nm (standard - custom also available) 400-865 nm (standard - custom also available)
Number of channels 4 7
Spectral bandwidth 10 nm 20 nm
Filter type Ion Assisted Deposition (IAD); custom low-fluorescence interference Ion Assisted Deposition (IAD); custom low-fluorescence interference
Cosine response 3% from 0 - 60°; 10% from 60 - 85° 3% from 0 - 60°; 10% from 60 - 85°
Out of band rejection 10-6 10-6
Typical NEI 2.5 X10-3 µWcm-2nm-1 2.5 X10-3 µWcm-2nm-1
Typical saturation 300 µWcm-2nm-1 300 µWcm-2nm-1
Depth rating 350 m 350 m
System time constant 0.011 seconds 0.011 seconds
Sample rate 7 Hz (24 Hz optional) 7 Hz (24 Hz optional)

Specifications for Upwelling Radiance Configuration

Field of view 10° in water (Half angle, half maximum); 14° in air (Half angle, half-maximum) 10° in water (Half angle, half maximum); 14° in air (Half angle, half-maximum)
Entrance aperture 9.5 mm diameter 9.5 mm diameter
Detectors Custom 13 mm2 Silicon photodiodes Custom 13 mm2 Silicon photodiodes
Bandwidth range 400-865 nm (standard - custom also available) 400-865 nm (standard - custom also available)
Number of channels 4 7
Spectral bandwidth 10 nm 20 nm
Filter type Ion Assisted Deposition (IAD); custom low-fluorescence interference Ion Assisted Deposition (IAD); custom low-fluorescence interference
Out of band rejection 10-6 10-6
Out of field rejection 5x10-4 >1.5 FOV 5x10-4 >1.5 FOV
Typical saturation 5 µWcm-2nm-1sr-1 5 µWcm-2nm-1sr-1
Depth rating 350 m 350 m
System time constant 0.011 seconds 0.011 seconds
Sample rate 7 Hz (24 Hz optional) 7 Hz (24 Hz optional)

Further details can be found in the manufacturer's specification sheet.

WETLabs ac-9 Plus Absorption and Attenuation meter

WETLabs ac-9 Plus is a flow-through absorption and attenuation meter that measures the absorption and attenuation coefficients of the water body. The ac-9 Plus supersedes the ac-9 sensor, with the added capability of accepting and integrating data from both CTDs and WETLabs ECO-VSF sensors. The data from this ancillary sensor can be incorporated into the serial data stream and can then be displayed and recorded using the WETView real time display program. Information about the volume scattering function (VSF) can also be obtained from the ac-9 Plus.

The following standard configurations are available for the AC9 Plus: ac-9 Plus and CTD; ac-9 Plus, CTD and ECO-VSF or ac-9 Plus, CTD and ECO-VSF 3. The ac-9 plus sensor can also be used with many CTDs including several SBE models.

Specifications

Spectral Range 410-715 nm
Band pass 10 nm per channel
Path length 10 or 25 cm
Beam cross-section 8 mm diameter (nominal)
Linearity > 99% R2
Output wavelengths 9
Accuracy ± 0.01 m-1
Precision ± 0.003 m-1 at 6 Hz; ± 0.001 m-1 at 1 Hz; ± 0.005 m-1 typ., 0.0012 m-1 max at 4 Hz
Dynamic Range 0.001-10 m-1
Temperature Range 0-30°C
Depth rating 500 m
Pressure sensor Optional

Further details can be found in the manufacturer's specification sheet.

AMT19 Bio-Optics - AC9 and UV Sensor profiles processing

Data Acquisition and Analysis

These data originate from analysis of data collected from the optics rig profiles from the RRS James Cook between 13th October and 1st December 2009. Optics profiles were made at or within one hour of local solar noon and mostly deployed on the sunward side of the ship. Temperature, salinity, flow rate, absorption, attenuation and downwelling vector irradiance were measured by the profiles. The instruments were deployed on the optics rig using 180 m of 6 mm dyneema on the deck winch. The upcast was carried out at 0.2 ms-1. Upon recovery, data from the ac-9, UV sensors and CTD were downloaded using WLHost.

Cast deployment took the form of two casts, the first cast was usually unfiltered. The second was fitted with a 0.2 µm filter.

BODC Data Processing Procedures

Data were submitted to BODC in 44 text files for the upcast of each profile and were saved to the archive with reference PML110037. The files were provided to BODC with the following metadata: cruise, date, time (in GMT), latitude, longitude and depth. 38 of the profiles were unfiltered, and 5 were filtered. Two duplicate files (amt19_opt002_ac9_suv_ctd_unf_091015.txt and amt19_opt003_ac9_suv_ctd_unf_091015.txt) were supplied so only the former was loaded to the system.

Parameter codes defined in BODC parameter dictionary were assigned to the variables as shown in the table below. No unit conversions were necessary as all the parameters were provided in equivilent units as in the BODC Parameter Dictionary. The attenuance and absorbance parameter codes represent measurements at the following wavelengths: 412, 440, 488, 510, 532, 555, 650, 676 and 715 nm. The downwelling vector irradiance parameter code respresents measurements at wavelengths 305, 325, 340, and 380 nm. The data contain some completely null channels for absorption, attenuation and irradiance. This is due to the fact that no attenuation and absorption measurements were obtained at the wavelengths that irradiance was measured at, and vice versa because each instrument only collects data at specific wavelengths. All parameters were transferred except for lat and lon. A parameter mapping table is provided below.

Originator's Parameter Description Units BODC Parameter Code Description Units Comments
Depth 2m depth binned metres DEPHPR01 Depth below surface of the water body by profiling pressure sensor and converted to seawater depth using UNESCO algorithm Metres -
Temp Temperature degC TEMPST01 Temperature of the water body by thermosalinograph and NO verification against independent measurements Degrees Celcius -
Sal Salinity PSU PSALST01 Practical salinity of the water body by thermosalinograph and computation using UNESCO 1983 algorithm and NO calibration against independent measurements Dimensionless -
Flow Flow rate litres min-1 INFLTF01 Flow rate through instrument Litres per minute Channel removed after transfer as the values were all zero.
a (unfiltered casts) absorption m-1 ABSPXAC9 Light absorbance (unspecified single wavelength)by the water body by transmissometer and calibration to read zero in clear water m-1 -
c (unfiltered casts) attenuation m-1 ATTNXAC9 Attenuance (unspecified single wavelength) per unit length of the water body by transmissometer and calibration to read zero in clear water m-1 -
c (filtered casts) attenuation m-1 ATNLTU01 Attenuance (unspecified single wavelength) per unit length of the water body dissolved plus reactive particulate <0.2 µm by transmissometer and calibration to read zero in clear water m-1 -
a (filtered casts) absorption m-1 ABSULT01 Light absorbance (unspecified single wavelength) per unit length of the water body dissolved plus reactive particulate <0.2 µm by transmissometer and calibration to read zero in clear water m-1 -
ed downwelling (vector) irradiance W m-2 nm-1 DWIRXXED Downwelling vector irradiance as energy (unspecified single wavelength) in the water body by radiometer W m-2 nm-1 -

Project Information

Oceans 2025 Theme 10, Sustained Observation Activity 1: The Atlantic Meridional Transect (AMT)

The Atlantic Meridional Transect has been operational since 1995 and through the Oceans 2025 programme secures funding for a further five cruises during the period 2007-2012. The AMT programme began in 1995 utilising the passage of the RRS James Clark Ross between the UK and the Falkland Islands southwards in September and northwards in April each year. Prior to Oceans 2025 the AMT programme has completed 18 cruises following this transect in the Atlantic Ocean. This sustained observing system aims to provide basin-scale understanding of the distribution of planktonic communities, their nutrient turnover and biogenic export in the context of hydrographic and biogeochemical provinces of the North and South Atlantic Oceans.

The Atlantic Meridional Transect Programme is an open ocean in situ observing system that will:

  • give early warning of any fundamental change in Atlantic ecosystem functionng
  • improve forecasts of the future ocean state and associated socio-economic impacts
  • provide a "contextual" logistical and scientific infrastructure for independently-funded national and international open ocean biogeochemical and ecological research.

The specific objectives are:

  • To collect hydrographic, chemical, ecological and optical data on transects between the UK and the Falkland Islands
  • To quantify the nature and causes of ecological and biogeochemical variability in planktonic ecosystems
  • To assess the effects of variability in planktonic ecosystems on biogenic export and on air-sea exchange of radiatively active gases

The measurements taken and experiments carried out on the AMT cruises will be closely linked to Themes 2 and 5. The planned cruise track also allows for the AMT data to be used in providing spatial context to the Sustained Observation Activities at the Porcupine Abyssal Plain Ocean Observatory (SO2) and the Western Channel Observatory (SO10).

More detailed information on this Work Package is available at pages 6 - 9 of the official Oceans 2025 Theme 10 document: Oceans 2025 Theme 10

Weblink: http://www.oceans2025.org/


Data Activity or Cruise Information

Cruise

Cruise Name JC039 (AMT19, JC040)
Departure Date 2009-10-13
Arrival Date 2009-12-01
Principal Scientist(s)Andrew Rees (Plymouth Marine Laboratory)
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