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Metadata Report for BODC Series Reference Number 1221157


Metadata Summary

Data Description

Data Category Currents -subsurface Eulerian
Instrument Type
NameCategories
Teledyne RDI Ocean Surveyor 150kHz vessel-mounted ADCP  current profilers
Instrument Mounting research vessel
Originating Country United Kingdom
Originator Dr John Allen
Originating Organization National Oceanography Centre, Southampton
Processing Status banked
Online delivery of data Download available - Ocean Data View (ODV) format
Project(s) Oceans 2025
Oceans 2025 Theme 2
 

Data Identifiers

Originator's Identifier D369/26
BODC Series Reference 1221157
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 2011-09-03 00:00
End Time (yyyy-mm-dd hh:mm) 2011-09-03 23:58
Nominal Cycle Interval 120.0 seconds
 

Spatial Co-ordinates

Start Latitude 26.81400 N ( 26° 48.8' N )
End Latitude 26.86917 N ( 26° 52.2' N )
Start Longitude 31.71450 W ( 31° 42.9' W )
End Longitude 31.83300 W ( 31° 50.0' W )
Positional Uncertainty 0.0 to 0.01 n.miles
Minimum Sensor or Sampling Depth 11.0 m
Maximum Sensor or Sampling Depth 391.0 m
Minimum Sensor or Sampling Height -
Maximum Sensor or Sampling Height -
Sea Floor Depth -
Sea Floor Depth Source -
Sensor or Sampling Distribution Sensor fixed with measurements made at multiple depths within a fixed range (e.g. ADCP) - The sensor is at a fixed depth, but measurements are made remotely from the sensor over a range of depths (e.g. ADCP measurements)
Sensor or Sampling Depth Datum Instantaneous - Depth measured below water line or instantaneous water body surface
Sea Floor Depth Datum -
 

Parameters

BODC CODERankUnitsTitle
DBINAA010MetresDepth (spatial coordinate) of ADCP bin relative to water surface {bin depth} in the water body
AADYAA011DaysDate (time from 00:00 01/01/1760 to 00:00 UT on day)
AAFDZZ011DaysTime (time between 00:00 UT and timestamp)
ACYCAA011DimensionlessSequence number
ALATGP011DegreesLatitude north relative to WGS84 by unspecified GPS system
ALONGP011DegreesLongitude east relative to WGS84 by unspecified GPS system
APEWGP012Centimetres per secondEastward velocity of measurement platform relative to ground surface by unspecified GPS system
APNSGP012Centimetres per secondNorthward velocity of measurement platform relative to ground surface by unspecified GPS system
ASAMSP002DecibelsSignal return amplitude from the water body by shipborne acoustic doppler current profiler (ADCP) beam 1
ASAMSP022DecibelsSignal return amplitude from the water body by shipborne acoustic doppler current profiler (ADCP) beam 2
ASAMSP032DecibelsSignal return amplitude from the water body by shipborne acoustic doppler current profiler (ADCP) beam 3
ASAMSP042DecibelsSignal return amplitude from the water body by shipborne acoustic doppler current profiler (ADCP) beam 4
LCEWAS012Centimetres per secondEastward velocity of water current (Eulerian measurement) in the water body by shipborne acoustic doppler current profiler (ADCP)
LCNSAS012Centimetres per secondNorthward velocity of water current (Eulerian measurement) in the water body by shipborne acoustic doppler current profiler (ADCP)
LERRAS012Centimetres per secondError velocity of water current in the water body by shipborne acoustic doppler current profiler (ADCP)
LREWAS012Centimetres per secondEastward velocity of water current relative to moving platform in the water body by shipborne acoustic doppler current profiler (ADCP)
LRNSAS012Centimetres per secondNorthward velocity of water current relative to moving platform in the water body by shipborne acoustic doppler current profiler (ADCP)
LRZAAS012Centimetres per secondUpward velocity of water current in the water body by shipborne acoustic doppler current profiler (ADCP)

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 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

RD Instruments- Ocean Surveyor 150kHz Vessel mounted ADCP.

Long-Range Mode
Vertical Resolution Cell Size3 Max. Range (m)1 Precision (cm/s)2
4m 325 - 350 30
8m 375 - 400 19
High-Precision Mode
Vertical Resolution Cell Size3 Max.Range (m)1 Precision (cm/s)2
4m 200 - 250 12
8m 220 - 275 9

1 Ranges at 1 to 5 knots ship speed are typical and vary with situation.
2 Single-ping standard deviation.
3 User's choice of depth cell size is not limited to the typical values specified.

Profile Parameters

  • Velocity long-term accuracy (typical): ±1.0%, ±0.5cm/s
  • Velocity range: -5 to 9m/s
  • # of depth cells: 1 - 128
  • Max ping rate: 1.5

Bottom Track

Maximum altitude (precision <2cm/s): 600m

Echo Intensity Profile

Dynamic range: 80dB
Precision: ±1.5dB

Transducer & Hardware

Beam angle: 30°
Configuration: 4-beam phased array
Communications: RS-232 or RS-422 hex-ASCII or binary output at 1200 - 115,200 baud
Output power: 1000W

Standard Sensors

Temperature (mounted on transducer)

  • Range: -5° to 45°C
  • Precision: ±0.1°C
  • Resolution: 0.03°

Environmental

Operating temperature: -5° to 40°C (-5° to 45°C)*
Storage temperature: -30° to 50°C (-30° to 60°C)*

*later instruments have greater range.

Web Page

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

Instrument Description

A Teledyne RD Instruments broadband 150 kHz (Ocean Surveyor) phased array style VM-ADCP was mounted in the hull 1.75 m to port of the keel, 33 m aft of the bow at the waterline, at an approximate depth of 5.3 m.

The VM-ADCP was configured to sample over 120 second intervals with 96 bins of 4 m length and a blank beyond transmit of distance of 4 m. The instrument was a broad-band phased array ADCP with 153.6 kHz frequency and a 30° beam angle.

Further information on VM-ADCP instrumentation can be found in the cruise report.

BODC Processing

The data arrived at BODC 40 individual PSTAR files. However, due to issues with the time channel an individual concatenated file needed to be used instead. The data were split into daily files and reformatted to the internal NetCDF format. The following table shows how the variables within the PSTAR files were mapped to the appropriate BODC parameter codes.

Originator's
variable
Units Description BODC
Parameter
code
Units Comments
Time seconds - - - -
bindepth metres Bin depth relative to sea surface DBINAA01 metres -
evelcal cm/s Eastward velocity from ADCP LREWAS01 cm/s Relative to ship's movement
nvelcal cm/s Northward velocity from ADCP LRNSAS01 cm/s Relative to ship's movement
velvert cm/s Upward current velocity of water column by ADCP LRZAAS01 cm/s -
velerr cm/s current velocity error in the water column by ADCP LERRAS01 cm/s -
intense1 db beam 1 return ASAMSP00 db -
intense2 db beam 2 return ASAMSP02 db -
intense3 db beam 3 return ASAMSP03 db -
intense4 db beam 4 return ASAMSP04 db -
good3bm % notifies when 3 beam solution used to generate absolute velocities - - not transferred
verr % percentage of transformations rejected - prevents ADCP from rejecting data due to error velocity - - not transferred
2+bmbad % percentage of pings where >1 beam is bad - - not transferred
good4bm % notifies when 4 beam solution used to generate absolute velocities - - not transferred
ve cm/s Ship's eastward velocity by GPS APEWGP01 cm/s -
vn cm/s Ship's northward velocity by GPS APNSGP01 cm/s -
absve cm/s Absolute eastward velocity of water column by ADCP LCEWAS01 cm/s -
absvn cm/s Absolute northward velocity of water column by ADCP LCNSAS01 cm/s -
lat deg latitude north (WGS84) using GPS system ALATGP01 deg -
lon deg longitude east (WGS84) using GPS system ALONGP01 deg -
distrun km distance run - - A derived parameter, therefore not transferred

The data were then visualised using the in-house EDSERPLO software. Suspect data were marked by adding an appropriate quality control flag. Missing data were marked by setting the data to an appropriate absent data value and absent data quality control flag.

Originator's Data Processing

The VMADCP was processed using Pstar. Further details can be found in the cruise report.

Field Calibrations

A calibration of the 150 kHz VM-ADCP was achieved using bottom tracking data following the departure from Santa Cruz, Tenerife, when the ship deviated around the island of La Gomera to obtain a few hours of water depth within bottom tracking range.

No further calibration was deemed necessary from inspection of the processed data during the cruise. Using straight, steady speed sections of standard two minute ensemble profiles over reasonably constant bottom depth the following calibrations for mis-alignment angle,Ø, and necessary amplification (tilt), A, were derived by comparing GPS derived component vectors of the vessel speed and direction with processed VM-ADCP bottom track determined component vectors of the vessel speed and direction:

Ø (mis-alignment angle):

  • mean = -0.6122
  • standard deviation = ± 0.2628

A (tilt):

  • mean = 1.00811
  • standard deviation = ± 0.0027

Further information on calibration of the VMADCP can be found in the cruise report.


Project Information

Oceans 2025 - The NERC Marine Centres' Strategic Research Programme 2007-2012

Who funds the programme?

The Natural Environment Research Council (NERC) funds the Oceans 2025 programme, which was originally planned in the context of NERC's 2002-2007 strategy and later realigned to NERC's subsequent strategy (Next Generation Science for Planet Earth; NERC 2007).

Who is involved in the programme?

The Oceans 2025 programme was designed by and is to be implemented through seven leading UK marine centres. The marine centres work together in coordination and are also supported by cooperation and input from government bodies, universities and other partners. The seven marine centres are:

  • National Oceanography Centre, Southampton (NOCS)
  • Plymouth Marine Laboratory (PML)
  • Marine Biological Association (MBA)
  • Sir Alister Hardy Foundation for Marine Science (SAHFOS)
  • Proudman Oceanographic Laboratory (POL)
  • Scottish Association for Marine Science (SAMS)
  • Sea Mammal Research Unit (SMRU)

Oceans2025 provides funding to three national marine facilities, which provide services to the wider UK marine community, in addition to the Oceans 2025 community. These facilities are:

  • British Oceanographic Data Centre (BODC), hosted at POL
  • Permanent Service for Mean Sea Level (PSMSL), hosted at POL
  • Culture Collection of Algae and Protozoa (CCAP), hosted at SAMS

The NERC-run Strategic Ocean Funding Initiative (SOFI) provides additional support to the programme by funding additional research projects and studentships that closely complement the Oceans 2025 programme, primarily through universities.

What is the programme about?

Oceans 2025 sets out to address some key challenges that face the UK as a result of a changing marine environment. The research funded through the programme sets out to increase understanding of the size, nature and impacts of these changes, with the aim to:

  • improve knowledge of how the seas behave, not just now but in the future;
  • help assess what that might mean for the Earth system and for society;
  • assist in developing sustainable solutions for the management of marine resources for future generations;
  • enhance the research capabilities and facilities available for UK marine science.

In order to address these aims there are nine science themes supported by the Oceans 2025 programme:

  • Climate, circulation and sea level (Theme 1)
  • Marine biogeochemical cycles (Theme 2)
  • Shelf and coastal processes (Theme 3)
  • Biodiversity and ecosystem functioning (Theme 4)
  • Continental margins and deep ocean (Theme 5)
  • Sustainable marine resources (Theme 6)
  • Technology development (Theme 8)
  • Next generation ocean prediction (Theme 9)
  • Integration of sustained observations in the marine environment (Theme 10)

In the original programme proposal there was a theme on health and human impacts (Theme 7). The elements of this Theme have subsequently been included in Themes 3 and 9.

When is the programme active?

The programme started in April 2007 with funding for 5 years.

Brief summary of the programme fieldwork/data

Programme fieldwork and data collection are to be achieved through:

  • physical, biological and chemical parameters sampling throughout the North and South Atlantic during collaborative research cruises aboard NERC's research vessels RRS Discovery, RRS James Cook and RRS James Clark Ross;
  • the Continuous Plankton Recorder being deployed by SAHFOS in the North Atlantic and North Pacific on 'ships of opportunity';
  • physical parameters measured and relayed in near real-time by fixed moorings and ARGO floats;
  • coastal and shelf sea observatory data (Liverpool Bay Coastal Observatory (LBCO) and Western Channel Observatory (WCO)) using the RV Prince Madog and RV Quest.

The data is to be fed into models for validation and future projections. Greater detail can be found in the Theme documents.


Oceans 2025 Theme 2: Marine Biogeochemical Cycles

Marine biogeochemical cycles are the key processes that control the cycling of climate-active gases within the surface ocean; the main transport mechanisms governing the supply of nutrients from deeper waters across the pycnocline; and the flux of material to deep water via the biological carbon pump. The broad aim of this Theme is to improve knowledge of major biogeochemical processes in the surface layer of the Atlantic Ocean and UK shelf seas in order to develop accurate models of these systems. This strategic research will result in predictions of how the ocean will respond to, and either ameliorate or worsen, climate change and ocean acidification.

Theme 2 comprises three Research Units and ten Work Packages. Theme 2 addresses the following pivotal biogeochemical pathways and processes:

  • The oceans and shelf seas as a source and sink of climate-active gases
  • The importance of the carbon and nitrogen cycles in the regulation of microbial communities and hence export and biogenic gas cycling
  • The biological pump and export of carbon into the ocean's interior
  • Processes that introduce nutrients into the euphotic zone
  • The direct impact of a high CO2 world (acidification) on mixed-layer biogeochemical cycles and feedbacks to the atmosphere via sea/air gas fluxes and the biological pump
  • The indirect impact of a high CO2 world (increased stratification and storminess) on the supply of nutrients to the surface layer of the ocean and hence on the biological carbon pump and air-sea gas fluxes
  • Cellular processes that mediate calcification in coccolithophores and how these are impacted by environmental change with a focus on elevated CO2 and ocean acidification
  • Inter- and intra-specific genetic diversity and inter-specific physiological plasticity in coccolithophores and the consequences of rapid environmental change

The official Oceans 2025 documentation for this Theme can be found using the following link: Oceans 2025 Theme 2


Data Activity or Cruise Information

Cruise

Cruise Name D369
Departure Date 2011-08-09
Arrival Date 2011-09-15
Principal Scientist(s)Mikhail V Zubkov (National Oceanography Centre, Southampton)
Ship RRS Discovery

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