Metadata Report for BODC Series Reference Number 1722560


Metadata Summary

Data Description

Data Category Currents -subsurface Eulerian
Instrument Type
NameCategories
Teledyne RDI 300kHz Workhorse Monitor direct-reading ADCP  current profilers
Instrument Mounting lowered unmanned submersible
Originating Country United Kingdom
Originator Dr Penny Holliday
Originating Organization National Oceanography Centre, Southampton
Processing Status QC in progress
Online delivery of data Download not available
Project(s) -
 

Data Identifiers

Originator's Identifier LADCP_071
BODC Series Reference 1722560
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 2015-06-14 16:35
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval 5.0 decibars
 

Spatial Co-ordinates

Latitude 56.83702 N ( 56° 50.2' N )
Longitude 8.33342 W ( 8° 20.0' W )
Positional Uncertainty 0.0 to 0.01 n.miles
Minimum Sensor or Sampling Depth 5.0 m
Maximum Sensor or Sampling Depth 120.0 m
Minimum Sensor or Sampling Height 15.0 m
Maximum Sensor or Sampling Height 130.0 m
Sea Floor Depth 135.0 m
Sea Floor Depth Source CTDDATA
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 Approximate - Depth is only approximate
Sea Floor Depth Datum Approximate - Depth is only approximate
 

Parameters

No Parameters for BODC Reference Number = 1722560

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

All casts were processed, although it was noted that casts shallower than 100-200 m often seemed to have problems, usually characterised as giving a profile that was significantly deeper than the true water depth. It is assumed this was due to confusing reflections at the seabed, and recommend that those profiles not be used (Casts 35, 37, 46, 47, 68-75, 79-81, 83). For more information see the cruise report page 35.


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

Instrument Description

The LADCP data were collected using the instrumentation detailed below:

Sensor Model Serial Number Calibration (UT) Comments
LADCP Teledyne RDI high-power Workhorse 300kHz 15288 - LDEO unit, downward looking

One Teledyne RDI Workhorse 300kHz ADCP was mounted on the Sea-Bird 9 11 plus CTD frame pointing downward (downlooker).

Teledyne RDI's Workhorse Monitor ADCP

The Workhorse Monitor acoustic doppler current profler (Teledyne RD Instruments) is a long-range and long-term self contained ADCP. It has a patented four beam signal (300, 600 or 1200 kHz) and a standard depth rating of 200m or 600m. It operates effectively between temperatures of -5°C and 45°C and has a velocity accuracy of ±1% ±5mm/s.

BODC Processing

LDEO processed data were provided by the originator in Matlab and ASCII formats. The LDEO processed data in ASCII format were converted into BODC internal format after discussion with the originator. All data provided were from the downward looking RDI 300 kHz Workhorse ADCP which was in operation at the time. The following table shows how the variables within the ASCII files were mapped to appropriate BODC parameter codes:

Originator's Parameter Name Units Description BODC Parameter Code Units Comments
z m Depth of LADCP bin ADEPZZ01 m -
u m s-1 Eastward velocity LCEWLW01 cm s-1 Units converted from m s-1 to cm s-1 by multiplying by 100.
v m s-1 Northward velocity LCNSLW01 cm s-1 Units converted from m s-1 to cm s-1 by multiplying by 100.
ev m s-1 Uncertainty estimates of LADCP velocity profile ERRVLDCP cm s-1 Units converted from m s-1 to cm s-1 by multiplying by 100.

All reformatted data were visualised using the in-house Edserplo software. Suspect and missing data were marked by adding an appropriate quality control flag.

Note that the more complex LDEO processed data are available on request in Matlab format as well as the unprocessed raw LADCP files.

Originator's Data Processing

Sampling Strategy

A total of 84 LADCP profiles were collected at all CTD stations in order to derive full-depth profiles of ocean velocity, as well as profiles of finestructure vertical shear.

Data processing

Preliminary shipboard processing of the LADCP data was carried out with the LDEO IX LADCP processing software using averaged one Hz ascii CTD data in order to correct the LADCP data for depth and sound speed.

Please refer to Thurnherr (2014) and cruise report for a more detailed processing methodology. However, please be aware that this processing guide is for software versions IX.7 to IX.10 only, and changes have been made between versions which have the potential for significantly changing the solutions.

References

Thurnherr, A. M., 2014. How To Process LADCP Data With the LDEO Software, Versions IX.7 - IX.10.


Project Information


No Project Information held for the Series

Data Activity or Cruise Information

Cruise

Cruise Name DY031
Departure Date 2015-05-29
Arrival Date 2015-06-17
Principal Scientist(s)N Penny Holliday (National Oceanography Centre, Southampton)
Ship RRS Discovery

Complete Cruise Metadata Report is available here


Fixed Station Information

Fixed Station Information

Station NameEllett Line/Extended Ellett Line Station T
CategoryOffshore location
Latitude56° 50.22' N
Longitude8° 19.98' W
Water depth below MSL120.0 m

Ellett Line/Extended Ellett Line: Station T

Station T is one of the fixed CTD stations, which together form The Extended Ellett Line. The line lies between Iceland and the Sound of Mull (Scotland) crossing the Iceland Basin and Rockall Trough via the outcrop of Rockall. As part of this initiative, CTD dips, together with associated discrete sampling of the water column, have typically been carried out annually at this station since September 1996.

Prior to September 1996, Station T was part of a shorter repeated survey section, consisting of 35 fixed stations, known as The Ellett Line (originally termed the Anton Dohrn Seamount Section). This line incorporated those stations across the Rockall Trough and Scottish shelf between Rockall and the Sound of Mull and was visited at regular intervals (usually at least once a year) between 1975 and January 1996.

Related Fixed Station activities are detailed in Appendix 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

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
Q value below limit of quantification

Appendix 1: Ellett Line/Extended Ellett Line Station T

Related series for this Fixed Station are presented in the table below. Further information can be found by following the appropriate links.

If you are interested in these series, please be aware we offer a multiple file download service. Should your credentials be insufficient for automatic download, the service also offers a referral to our Enquiries Officer who may be able to negotiate access.

Series IdentifierData CategoryStart date/timeStart positionCruise
91131CTD or STD cast1976-05-20 23:30:0056.85 N, 8.365 WRRS Challenger CH8/76
91690CTD or STD cast1976-05-28 02:26:0056.8566 N, 8.3333 WRRS Challenger CH8/76
91930CTD or STD cast1977-04-14 22:30:0056.8516 N, 8.3333 WRRS Challenger CH6B/77
94301CTD or STD cast1977-07-25 06:30:0056.8466 N, 8.34 WRRS Challenger CH11/77
88669CTD or STD cast1977-08-21 10:36:0056.845 N, 8.325 WRRS Challenger CH13/77
92238CTD or STD cast1978-02-02 22:42:0056.8416 N, 8.3133 WRRS Challenger CH2/78
94583CTD or STD cast1978-04-17 18:26:0056.8433 N, 8.33 WRRS Challenger CH6/78
314361CTD or STD cast1978-11-06 02:21:0056.85 N, 8.3367 WRRS Challenger CH14B/78
98781CTD or STD cast1979-05-21 21:33:0056.85 N, 8.3333 WRRS Challenger CH7/79
99852CTD or STD cast1979-06-27 22:44:0056.855 N, 8.3383 WRRS Shackleton S5/79
95863CTD or STD cast1979-09-13 21:02:0056.8466 N, 8.3216 WRRS Challenger CH13/79
96055CTD or STD cast1979-10-29 15:31:0056.8466 N, 8.3383 WRRS Challenger CH16/79
187760CTD or STD cast1980-03-04 13:21:0056.85 N, 8.335 WRRS Challenger CH4/80
189686CTD or STD cast1980-06-01 12:21:0056.84 N, 8.33 WRRS Challenger CH9B/80
188450CTD or STD cast1981-04-21 07:13:0056.8516 N, 8.3383 WRRS Challenger CH6B/81
192288CTD or STD cast1981-07-13 02:36:0056.85 N, 8.3383 WRRS Challenger CH10/81
189127CTD or STD cast1982-04-26 23:08:0056.8483 N, 8.3183 WRRS Challenger CH7A/82
193427CTD or STD cast1983-05-24 12:10:0056.8483 N, 8.3316 WRRS Challenger CH7B/83
313185CTD or STD cast1984-06-27 11:58:0056.8517 N, 8.3283 WRRS Challenger CH2/84
257949CTD or STD cast1984-12-02 12:39:0056.8466 N, 8.33 WRRS Challenger CH10/84
258399CTD or STD cast1985-01-26 23:31:0056.85 N, 8.3333 WRRS Challenger CH1/85
253856CTD or STD cast1985-05-08 11:36:0056.85 N, 8.3333 WRRS Challenger CH4/85
261162CTD or STD cast1985-08-20 00:00:0056.85 N, 8.3333 WRRS Challenger CH8/85
264147CTD or STD cast1987-01-10 03:21:0056.85 N, 8.3333 WRRS Challenger CH9
250601CTD or STD cast1987-04-30 14:29:0056.8516 N, 8.3333 WRRS Challenger CH14
255931CTD or STD cast1987-08-31 13:32:0056.8366 N, 8.3333 WRRS Frederick Russell FR18/87
251653CTD or STD cast1987-11-27 22:33:0056.8366 N, 8.3333 WRRS Challenger CH22
266953CTD or STD cast1988-03-06 16:52:0056.8433 N, 8.3283 WRRS Challenger CH25
263992CTD or STD cast1988-06-20 16:33:0056.8366 N, 8.3316 WRRS Challenger CH30
265323CTD or STD cast1989-01-24 09:26:0056.8333 N, 8.3333 WRRS Discovery D180
265335CTD or STD cast1989-01-24 09:37:0056.8333 N, 8.3333 WRRS Discovery D180
265833CTD or STD cast1989-05-06 00:42:0056.8333 N, 8.3333 WRV Lough Foyle LF1/89
317611CTD or STD cast1989-08-05 04:40:0056.8383 N, 8.3333 WRV Lough Foyle LF2/89
316785CTD or STD cast1989-11-25 20:18:0056.835 N, 8.3333 WRRS Charles Darwin CD44
315966CTD or STD cast1990-12-10 18:27:0056.8367 N, 8.335 WRRS Challenger CH74A_1
382468CTD or STD cast1991-02-26 14:13:0056.8333 N, 8.3333 WRRS Challenger CH75B
316171CTD or STD cast1991-07-02 09:58:0056.8367 N, 8.335 WRRS Challenger CH81
386469CTD or STD cast1992-09-26 12:49:0056.8367 N, 8.3333 WRRS Challenger CH97
385952CTD or STD cast1993-05-20 05:06:0056.8367 N, 8.33 WRRS Challenger CH103
388058CTD or STD cast1993-09-10 21:02:0056.8348 N, 8.33 WRRS Challenger CH105
389049CTD or STD cast1994-03-15 10:48:0056.8367 N, 8.3333 WRRS Challenger CH110
389535CTD or STD cast1994-05-08 10:54:0056.8367 N, 8.3333 WRRS Challenger CH112
390770CTD or STD cast1994-08-16 11:36:0056.8357 N, 8.326 WRRS Challenger CH114
390782CTD or STD cast1994-08-16 12:51:0056.8357 N, 8.326 WRRS Challenger CH114
391945CTD or STD cast1994-11-24 11:48:0056.8367 N, 8.3333 WRRS Challenger CH116
435575CTD or STD cast1995-05-01 08:14:0056.8367 N, 8.3333 WRRS Charles Darwin CD92B
390376CTD or STD cast1995-07-30 03:52:0056.8377 N, 8.3308 WRRS Challenger CH120
433998CTD or STD cast1996-01-12 10:34:0056.8367 N, 8.3333 WRRS Challenger CH124
1289280Water sample data1996-01-12 10:34:0056.8367 N, 8.3333 WRRS Challenger CH124
1014539CTD or STD cast1996-09-30 14:10:0056.8365 N, 8.3375 WRRS Discovery D223A
1850039Water sample data1996-09-30 14:27:0056.83657 N, 8.33748 WRRS Discovery D223A
1008097CTD or STD cast1997-09-14 16:37:0056.83667 N, 8.333 WRRS Discovery D230
1305066Water sample data1997-09-14 16:46:0056.83671 N, 8.33307 WRRS Discovery D230
1077123CTD or STD cast1999-06-04 19:56:0056.8365 N, 8.33617 WNot applicable
1070591CTD or STD cast1999-09-11 10:44:0056.83167 N, 8.33483 WRRS Discovery D242
1251927Water sample data1999-09-11 10:52:0056.83167 N, 8.33483 WRRS Discovery D242
1075073CTD or STD cast2000-02-03 00:55:0056.83583 N, 8.33317 WRRS Discovery D245
676779CTD or STD cast2001-05-20 02:24:0056.83217 N, 8.32017 WRRS Discovery D253
845120CTD or STD cast2003-07-24 23:42:0056.83752 N, 8.33482 WFS Poseidon PO300_2
667045CTD or STD cast2004-07-12 23:28:0056.85133 N, 8.33383 WFS Poseidon PO314
896887CTD or STD cast2005-10-25 11:23:0056.83584 N, 8.33416 WRRS Charles Darwin CD176
776707CTD or STD cast2006-10-26 12:49:1256.83983 N, 8.34083 WRRS Discovery D312
847544CTD or STD cast2007-08-30 19:24:1556.831 N, 8.32976 WRRS Discovery D321B
880965CTD or STD cast2008-05-23 13:16:0056.83383 N, 8.33717 WFRV Scotia 0508S
1616983Water sample data2008-05-23 13:16:0056.83383 N, 8.33717 WFRV Scotia 0508S
954394CTD or STD cast2009-06-20 20:14:5956.8364 N, 8.33456 WRRS Discovery D340A
1052848CTD or STD cast2010-05-21 01:29:3856.84767 N, 8.32867 WRRS Discovery D351
1896897Water sample data2010-05-21 01:44:0056.84726 N, 8.32908 WRRS Discovery D351
1203360CTD or STD cast2012-08-03 04:16:0056.83655 N, 8.33334 WRRS Discovery D379
1220732CTD or STD cast2013-05-24 14:57:1956.8365 N, 8.3325 WRRS James Cook JC086
1371296CTD or STD cast2014-07-16 14:25:3556.8371 N, 8.333 WRRS James Clark Ross JR20140531 (JR302)
1723471CTD or STD cast2015-06-14 16:34:3656.837 N, 8.3334 WRRS Discovery DY031
1879384Water sample data2015-06-14 16:43:0056.83702 N, 8.33343 WRRS Discovery DY031
1764728CTD or STD cast2016-06-19 08:35:5556.8378 N, 8.3336 WRRS Discovery DY052
1765861Currents -subsurface Eulerian2016-06-19 08:36:2356.83783 N, 8.33357 WRRS Discovery DY052
1875045Water sample data2016-06-19 08:44:0056.83783 N, 8.33357 WRRS Discovery DY052