Metadata Report for BODC Series Reference Number 1014484

Metadata Summary

Data Description
Data Category Currents -subsurface Eulerian
Instrument Type
NameCategories
Teledyne RDI Workhorse Long-Ranger ADCP  current profilers
Instrument Mounting subsurface mooring
Originating Country United Kingdom
Originator Prof Toby Sherwin
Originating Organization Scottish Association for Marine Science
Processing Status QC in progress
Project(s) Oceans 2025
Oceans 2025 Theme 10
Oceans 2025 Theme 10 SO4
 

Data Identifiers

Originator's Identifier WTR_07_08_CO
BODC Series Reference 1014484
 

Time Co-ordinates(UT)
Start Time (yyyy-mm-dd hh:mm) 2007-09-02 17:45
End Time (yyyy-mm-dd hh:mm) 2008-05-18 07:00
Nominal Cycle Interval 900.0 seconds
 

Spatial Co-ordinates

Latitude 60.24517 N ( 60° 14.7' N )
Longitude 9.01267 W ( 9° 0.8' W )
Positional Uncertainty 0.0 to 0.01 n.miles
Minimum Sensor Depth 689.4 m
Maximum Sensor Depth 1283.54 m
Minimum Sensor Height 26.67 m
Maximum Sensor Height 620.81 m
Sea Floor Depth 1310.21 m
Sensor Distribution Sensor fixed, measurements made at fixed depths - 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 Depth Datum Instantaneous - Depth measured below water line or instantaneous water body surface
Sea Floor Depth Datum Instantaneous - Depth measured below water line or instantaneous water body surface
 

Parameters
BODC CODE Rank Units Title
BINNUMBR 0 Dimensionless Bin number
AADYAA01 1 Days Date (time from 00:00 01/01/1760 to 00:00 UT on day)
AAFDZZ01 1 Days Time (time between 00:00 UT and timestamp)
ACYCAA01 1 Dimensionless Sequence number
PPSBSF01 1 Metres Depth below surface of the water body by fixed in-situ pressure sensor and correction to zero at sea level and conversion to depth using unspecified algorithm
PTCHEI01 1 Degrees Orientation (pitch) of measurement platform by inclinometer
ROLLFG01 1 Degrees Orientation (roll angle) of measurement platform by triaxial fluxgate compass
TEMPPR01 1 Degrees Celsius Temperature of the water body
ASAMAP00 2 Decibels Signal return amplitude from the water body by moored acoustic doppler current profiler (ADCP) beam 1
ASAMAP02 2 Decibels Signal return amplitude from the water body by moored acoustic doppler current profiler (ADCP) beam 2
ASAMAP03 2 Decibels Signal return amplitude from the water body by moored acoustic doppler current profiler (ADCP) beam 3
ASAMAP04 2 Decibels Signal return amplitude from the water body by moored acoustic doppler current profiler (ADCP) beam 4
ASAMAPAV 2 Decibels Signal return amplitude from the water body by moored acoustic doppler current profiler (ADCP) and averaging of all functional beams
DBINAA01 2 Metres Depth below sea surface (ADCP bin)
LCEWAP01 2 Centimetres per second Eastward current velocity (Eulerian) in the water body by moored acoustic doppler current profiler (ADCP)
LCNSAP01 2 Centimetres per second Northward current velocity (Eulerian) in the water body by moored acoustic doppler current profiler (ADCP)
LRZAAP01 2 Centimetres per second Upward current velocity in the water body by moored acoustic doppler current profiler (ADCP)
PCGDAP00 2 Percent Acceptable proportion of signal returns by moored acoustic doppler current profiler (ADCP) beam 1
PCGDAP02 2 Percent Acceptable proportion of signal returns by moored acoustic doppler current profiler (ADCP) beam 2
PCGDAP03 2 Percent Acceptable proportion of signal returns by moored acoustic doppler current profiler (ADCP) beam 3
PCGDAP04 2 Percent Acceptable proportion of signal returns by moored acoustic doppler current profiler (ADCP) beam 4
 

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

The series displays a significant degree of mooring knockdown. The instrument manufacturer, Teledyne, considers a pitch or roll greater than 20° to be excessive. As a consequence, warning flags have been assigned to all corresponding current velocities and these particular data cycles should be used with caution.

Data Quality Report

It should be noted that the originator has not applied any corrections for magnetic variation.

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

Teledyne RDI's Workhorse Long Ranger ADCP

The Workhorse Long-Ranger acoustic doppler current profler (Teledyne RD Instruments) is a long-range and long-term self contained ADCP. It has a patented broadband signal (75 kHz) and a standard depth rating of 1500m. It operates effectively between temperatures of -5°C and 45°C and has a velocity accuracy of ±1% ±5mm/s.

The instrument comprises:

Wyville Thomson Ridge Moored Acoustic Doppler Current Profiler: Originator Processing

This document outlines the procedures undertaken by the data originator to process and quality assure ADCP data collected as part of a long-term monitoring programme studying transport across the Wyville Thomson Ridge.

Data Processing

The raw binary data are downloaded from the instrument and converted into Matlab format (one file per deployment) using Teledyne RDI-supplied WinADCP software.

Derived 2-dimensional parameters exported from WinADCP have had bin mapping applied to account for the complex geometry involved in extracting currents relative to earth coordinates. In addition the WinADCP software performs a number of calculations needed to determine velocities.

Wyville Thomson Ridge Moored Acoustic Doppler Current Profiler: Processing undertaken by BODC

Data are sent to BODC in .MAT format with one file provided for each ADCP mooring deployment. These files have undergone some initial processing using WinADCP software, but no detailed validation or correction to the data has subsequently been conducted by the data originator. The original .MAT files are archived at BODC and are available upon request.

A number of key parameters from the original .MAT files, as specified by the data originator, are then reformatted into QXF - a NetCDF subset. To enable future analyses, the beam signal return data are preserved in the QXF files, even where bins are null. During the reformatting exercise, bin depths are calculated in order to produce a 2-dimensional bin depth array:

DBINAA01 = ANDepthmm - RDIBin1Mid -((RDIBinSize*(SerBins-1))
Where:
ANDepthmm = depth below surface of the water body as recorded by the ADCP
RDIBin1Mid = distance from ADCP to middle of first bin
RDIBinSize = bin size
SerBins = bin number

Standard parameter codes, that accurately describe the data and any unit conversions, are assigned. These are detailed in the table below.

Originator' Variable Units Description BODC Parameter Code Units Comments
SerNmmpersec mm s-1 Northward current veolcity in the water body LCNSAP01 cm s-1 Unit conversion applied during transfer by dividing original value by 10
SerEmmpersec mm s-1 Eastward current velocity in the water body LCEWAP01 cm s-1 Unit conversion applied during transfer by dividing original value by 10
SerVmmpersec mm s-1 Upward current velocity in the water body LRZAAP01 cm s-1 Unit conversion applied during transfer by dividing original value by 10
AnDepthmm mm Depth below surface of the water body PPSBSF01 m Unit conversion applied during transfer by dividing original value by 1000
AnT100thDeg °C (*100) Temperature of the water body TEMPPR01 °C Unit conversion applied during transfer by dividing original value by 100
AnR100thDeg degrees (*100) Roll ROLLEI01 degrees Unit conversion applied during transfer by dividing original value by 100
AnP100thDeg degrees (*100) Pitch PTCHEI01 degrees Unit conversion applied during transfer by dividing original value by 100
SerEA1cnt decibels Orientation signal return amplitude from the water body by ADCP beam 1 ASAMAP00 decibels -
SerEA2cnt decibels Orientation signal return amplitude from the water body by ADCP beam 2 ASAMAP02 decibels -
SerEA3cnt decibels Orientation signal return amplitude from the water body by ADCP beam 3 ASAMAP03 decibels -
SerEA4cnt decibels Orientation signal return amplitude from the water body by ADCP beam 4 ASAMAP04 decibels -
SerEAAcnt decibels Signal return amplitude from the water body by moored ADCP and averaging of all functional beams ASAMAPAV decibels -
SerPG1 % Acceptable proportion of signal returns from ADCP beam 1 PCGDAP00 % -
SerPG2 % Acceptable proportion of signal returns from ADCP beam 2 PCGDAP02 % -
SerPG3 % Acceptable proportion of signal returns from ADCP beam 3 PCGDAP03 % -
SerPG4 % Acceptable proportion of signal returns from ADCP beam 4 PCGDAP04 % -
SerBin - Bin number BINNUMBR - -
- - BODC derived depth below surface (ADCP bin) DBINAA01 m -

The data are screened visually and any spikes, or instrument malfunctions, are highlighted with BODC quality control flags. Series are trimmed at the start/end to remove phases from the mooring deployment/recovery. Subtle/brief phases of mooring adjustment at the start of series are highlighted with caution flags alone.

Documentation is prepared describing the collection, processing and quality of each data series. These are linked to each series to enable standalone use of the data in the future.

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:

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:

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:

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

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:

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 10

Oceans 2025 is a strategic marine science programme, bringing marine researchers together to increase people's knowledge of the marine environment so that they are better able to protect it for future generations.

Theme 10: Integration of Sustained Observations in the Marine Environment spans all marine domains from the sea-shore to the global ocean, providing data and knowledge on a wide range of ecosystem properties and processes (from ocean circulation to biodiversity) that are critical to understanding Earth system behaviour and identifying change. They have been developed not merely to provide long-term data sets, but to capture extreme or episodic events, and play a key role in the initialisation and validation of models. Many of these SOs will be integrated into the newly developing UK Marine Monitoring Strategy - evolving from the Defra reports Safeguarding our Seas (2002) and Charting Progress (2005), thus contributing to the underpinning knowledge for national marine stewardship. They will also contribute to the UK GOOS Strategic Plan (IACMST, 2006) and the Global Marine Assessment.

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

Oceans 2025 Theme 10, Sustained Observation Activity 4: The Extended Ellett Line

The Ellett Line (begun in 1975 and since 1996 the Extended Ellett Line from Scotland to Iceland) crosses important north Atlantic Meridional Overturning Circulation (MOC) components and thus provides an additional contribution to understanding the north Atlantic response to climate change. Sustained Observation Activity (SO) 4 will repeat this section annually collecting a wide variety of physical and biogeochemical measurements, and will, to enhance the time variable component, make use of Argo floats and gliders. SO 4 will be implemented by physical, biological and chemical scientists at the National Oceanography Centre, Southampton (NOCS) and the Scottish Association for Marine Science (SAMS).

SO 4 formally contributes to the Department for Environment, Food and Rural Affairs (DEFRA)-funded Marine Environmental Change Network (MECN). Established in 2002 to coordinate and promote the collection and utilisation of marine time-series and long-term data sets, the goal of the network is to use long-term marine environmental data from around the British Isles and Ireland to separate natural fluctuations from global, regional and local anthropogenic impacts.

The specific deliverables for SO 4 are:

More detailed information on this Work Package is available at pages 15 - 16 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 D321B
Departure Date 2007-08-24
Arrival Date 2007-09-09
Principal Scientist(s)Toby J Sherwin (Scottish Association for Marine Science)
Ship RRS Discovery

Complete Cruise Metadata Report is available here

Fixed Station Information

Fixed Station Information

Station NameWyville Thomson Ridge
CategoryOffshore area
Latitude60° 14.70' N
Longitude7° 27.00' W
Water depth below MSL

Wyville Thomson Ridge

The Wyville Thomson Ridge marks the boundary between the Rockall Trough and the Faroe-Shetland Channel. The Ridge is an important area for the study of deep ocean circulation and has been the focus of many studies, by various institutions, since 1975.

The Wyville Thomson Ridge is also a location of focused mooring activities led by the Scottish Association for Marine Science (SAMS). See Wyville Thomson Ridge Moored ADCP for specific details.

Measurements made along and around the Wyville Thomson Ridge lie within a box bounded by co-ordinates 59° 40' N, 9° 54' W at the southwest corner and 60° 50' N, 5° 00' W at the northeast corner.

Other Series linked to this Fixed Station for this cruise - 847673 847685 847697 847704 847716 847728 847741 847753 847765 847777 847789 847790 847808 847821 847833 847901

Other Cruises linked to this Fixed Station (with the number of series) - 0703S (132) 0706S (1) 1403S (1) CD176 (14) D312 (9) D321B (16) D340A (26) PO300_2 (23)

Fixed Station Information

Station NameWyville Thomson Ridge Moored ADCP
CategoryOffshore area
Latitude60° 14.40' N
Longitude8° 52.20' W
Water depth below MSL1200.0 m

Wyville Thomson Ridge Moored Acoustic Doppler Current Profiler

Introduction

The Wyville Thomson Ridge is an area of the North Atlantic Ocean floor running in a south easterly direction from the Faroe Bank to the Scottish continental shelf. The most eastern pathway across the Wyville Thomson Ridge marks a noteable boundary between cold and warm deep water at the southern edge of the Faroe-Shetland Channel. To enable monitoring of transport across this region the Scottish Association for Marine Science (SAMS) has deployed a succession of Acoustic Doppler Current Profiler (ADCP) moorings in the Wyville Thomson Ridge region since 2003.

These moorings are situated approximately 1.2 km north-west of the formal Faroe end of the Fair Isle-Munken (FIM) line and constitute part of a larger long term monitoring programme studying the nature of flow across the ridge, and the causes of its variability.

Instrument Deployment History

The following table summarises the SAMS moored ADCP deployments at the Wyville Thomson Ridge;

Mooring ID Deployment Cruise Deployment Date Recovery Cruise Recovery Date Position ADCP Serial Number Water Depth (m)
Ridge PO300_2 01/08/2003 0804S_1 26/05/2004 60.183°N 7.734°W 1644 647
1a 1403S 26/09/2003 0804S_1 21/05/2004 60.239°N 8.868°W 1767 1214
1b CD176 16/10/2005 0706S 07/05/2006 60.239°N 8.870°W 1644 1137
2a 0706S 07/05/2006 D312 29/10/2006 60.250°N 8.910°W 1644 1219
2b,c D312 29/10/2006 D321B 02/09/2007 60.250°N 8.917°W 1644 1225
3a D321B 02/09/2007 0508S 18/05/2008 60.245°N 9.013°W 9201 1310
3b 0508S 19/05/2008 D340A LOST 60.245°N 9.013°W 9201 1290
3c D340A 23/06/2009 - - 60.245°N 9.013°W 1767 1148

References

Sherwin, T.J., Griffiths, C.R., Inall, M.E., and Turrell, W.R., 2008. Quantifying the overflow across the Wyville Thomson Ridge into the Rockall Trough, Deep-Sea Research, 55, 4, 396-404.

Other Cruises linked to this Fixed Station (with the number of series) - 0706S (1) 1403S (1) CD176 (1) D312 (1) PO300_2 (1)

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