Metadata Report for BODC Series Reference Number 88842
No Problem Report Found in the Database
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."
Bissett-Berman 9060 Salinity Temperature and Depth
The B-B 9060 STD measured salinity, temperature and depth and whose analogue output was in graphical form. The plots created were of salinity and temperature versus depth which had to be manually digitised.
RRS Challenger 13/77 STD Data Documentation
Documentation for the STD data collected on RRS Challenger Cruise 13/77 (August 1977) by the Scottish Marine Biological Association, Oban, Argyll, Scotland, UK, under the direction of D. J. Ellett.
The instrument used was a Bissett Berman STD system and the data were logged on a Hewlett Packard 9820. Instrument lowering and raising speeds between 0.5 m/s and 1 m/s. An acoustic pinger was placed above the STD to give an accurate depth measurement, this could then be used to check the STD pressure calibration. An NIO bottle with reversing thermometers was placed above the pinger, within 2m of the STD system. A bottle sample was taken at the bottom of the cast providing the temperature and salinity are uniform at that point. If large temperature or salinity gradients were present then the bottle sample was triggered at a suitable site on the upcast. A surface salinity sample was also taken at the start of the dip.
The STD was not calibrated in the laboratory. The manufacturer's calibration was used and water samples taken to check the calibration and apply corrections where necessary.
The manufacturer's calibration was used to convert the raw data to physical units using the equation below:
Temperature (°C) = (106 /Pt - 2238.68)/55.84
where Pt is the temperature period in microseconds.
These values were then plotted against the water bottle (i.e. reversing thermometer) temperatures and a regression line fitted to the data such that:
Temperature(WB) = m x Temperature(STD) + c
Then the regression coefficients (m and c) were applied to correct the STD temperature data - these are given in the table below.
The manufacturer's calibration was used to convert the raw data to physical units using the equation below:
Salinity (ppt) = (10 6 /Ps - 4995)/290.6 + 30
where Ps is the salinity period in microseconds.
These values were then plotted against the STD salinity and a regression line fitted to the data such that:
Salinity(WB) = m x Salinity(STD) + c + (m1 x Pressure + c1)/1000
Then the regression coefficients were applied to correct the STD salinity data. The data showed a salinity - pressure dependency, this was corrected by plotting delta-S (i.e. calibrated salinity - calculated salinity) against pressure to determine the slope (m1) and intercept (c1).
These were then incorporated into the equation as shown above. The regression coefficients are given in the table below.
The depths from the acoustic pinger were noted where the bottle samples were taken and then used to check the calibration of the pressure sensor - unless calibration values were available from the reversing thermometers. The equation below was used to convert the pressure period to physical units.
Pressure = (10 6 /Pd - 9712)/0.26267
where Pd is the pressure period in microseconds
A regression fit was carried out using the calibration values and the slope and intercept determined. The pressure values could then be corrected using:
Pressure (CORR) = m x Pressure(STD) + c
The fit of the STD data to the water bottle calibration data is given in the table below:
|Variable||Slope (m)||Intercept (c)||Standard deviation|
|Temperature (° C)||1.0042||-0.0229||0.023|
Obvious wild points were edited out of the calibration file and the calibration programs run to obtain values for the slopes and intercepts for temperature, pressure and salinity. These were then applied to the uncalibrated data and sigma-t was calculated. The data values were then sieved to ensure a minimum separation between pressure values of 1 dbar.
The data were then visually inspected and major spikes flagged.
Sharples, F. (1987).
A new data bank of SMBA STD/CTD observations in the Rockall Trough 1975-84. SMBA Marine Physics Group Report No. 36.
Graham, J.M., Sharples, F., Meldrum, D.T. and Edwards, A. (1987).
STD observations in the Rockall Trough 1975-77. SMBA Marine Physics Group Report No. 39.
Selected temperature, salinity and depth data from RRS Challenger cruise 13/1977. SMBA Marine Physics Group Report No. 49. July 1987.
No Project Information held for the Series
|Principal Scientist(s)||David J Ellett (Scottish Marine Biological Association)|
Complete Cruise Metadata Report is available here
Fixed Station Information
|Station Name||Ellett Line/Extended Ellett Line Station B|
|Latitude||57° 34.02' N|
|Longitude||13° 19.98' W|
|Water depth below MSL||210.0 m|
Ellett Line/Extended Ellett Line: Station B
Station B is one of 58 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 B 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.
Other Cruises linked to this Fixed Station (with the number of series) - 0508S (1) 0700S (1) 0703S (1) CD176 (1) CD44 (1) CD92B (1) CH10/84 (1) CH103 (1) CH105 (1) CH11/77 (1) CH11/83 (1) CH112 (1) CH114 (1) CH11B/78 (1) CH120 (1) CH124 (1) CH14 (1) CH14A/75 (1) CH2/78 (2) CH2/84 (1) CH4/80 (1) CH4/85 (1) CH5A/76 (1) CH6/78 (1) CH67A (1) CH6B/77 (1) CH6B/81 (1) CH7/80 (1) CH71A (1) CH75B (1) CH7B/82 (1) CH8/76 (1) CH8/85 (1) CH81 (1) CH9/78 (1) CH97 (1) D180 (1) D242 (1) D312 (1) D321B (1) D340A (1) D351 (1) LF1/89 (1) LF2/89 (1) PO300_2 (1)
Fixed Station Information
|Station Name||Ellett Line|
The Ellett Line is a hydrographic transect consisting of 35 individual fixed stations which were occupied, usually at least once a year, between 1975 and 1996. The time series is named after the scientist David Ellett, who coordinated the survey work at Dunstaffnage Marine Laboratory (DML), near Oban. The transect ran between the north west coast of Scotland to the small outcrop of Rockall, via the Anton Dohrn Seamount - a prominent bathymetric feature in the Rockall Trough (see map). STD/CTD dips and associated water sampling for the analysis of nutrients were routinely performed during each station occupation.
In 1996 the transect was lengthened to incorporate new additional fixed stations crossing the Iceland Basin from Rockall to Iceland. This transect, which is still routinely occupied annually, is now known as the Extended Ellett Line and is a collaborative effort between scientists at Dunstaffnage Marine Laboratory and the Southampton site of the National Oceanography Centre (NOC).
Map of standard stations (1975-1996)
Map produced using the GEBCO Digital Atlas
The white triangles indicate the nominal positions of the Ellett Line stations (1975- 1996). Measurements made along the Ellett Line lie within a box bounded by co-ordinates 56° 40.02' N, 13° 42.0' W at the south west corner and 57° 37.2' N, 6° 7.98' W at the north east corner.
Nominal Ellett Line stations (1975-1996)
Listed below are nominal details of the standard hydrographic stations that formed the Ellett Line between 1975 and January 1996.
|A||57.583 N||13.633 W||130 m||10.0 nm|
|B||57.567 N||13.333 W||210 m||9.7 nm|
|C||57.550 N||13.000 W||330 m||10.8 nm|
|D||57.542 N||12.867 W||1000 m||4.3 nm|
|E||57.533 N||12.633 W||1658 m||7.6 nm|
|F||57.508 N||12.250 W||1817 m||12.5 nm|
|G||57.492 N||11.850 W||1812 m||13.0 nm|
|H||57.483 N||11.533 W||2020 m||10.3 nm|
|I||57.467 N||11.317 W||750 m||7.0 nm|
|J||57.450 N||11.083 W||550 m||7.6 nm|
|K||57.400 N||10.867 W||850 m||7.6 nm|
|L||57.367 N||10.667 W||2076 m||6.8 nm|
|M||57.300 N||10.383 W||2340 m||10.1 nm|
|N||57.233 N||10.050 W||2100 m||11.5 nm|
|O||57.150 N||9.700 W||1900 m||12.4 nm|
|P||57.100 N||9.417 W||1050 m||9.7 nm|
|Q||57.050 N||9.217 W||350 m||7.2 nm|
|R||57.000 N||9.000 W||135 m||7.7 nm|
|S||56.950 N||8.783 W||125 m||7.7 nm|
|15G||56.883 N||8.500 W||125 m||10.1 nm|
|T||56.837 N||8.333 W||120 m||6.1 nm|
|14G||56.808 N||8.167 W||115 m||5.7 nm|
|13G||56.783 N||8.000 W||110 m||5.7 nm|
|12G||56.758 N||7.833 W||80 m||5.7 nm|
|11G||56.733 N||7.667 W||55 m||5.7 nm|
|10G||56.733 N||7.500 W||220 m||5.5 nm|
|9G||56.733 N||7.333 W||160 m||5.5 nm|
|8G||56.733 N||7.167 W||175 m||5.5 nm|
|7G||56.733 N||7.000 W||145 m||5.5 nm|
|6G||56.733 N||6.750 W||35 m||8.2 nm|
|5G||56.733 N||6.600 W||75 m||4.9 nm|
|4G||56.733 N||6.450 W||115 m||4.9 nm|
|3G||56.708 N||6.367 W||75 m||3.1 nm|
|2G||56.683 N||6.283 W||40 m||3.2 nm|
|1G||56.667 N||6.133 W||190 m||5.0 nm|
History of Ellett Line occupations (1975-January 1996)
|BODC Cruise Identifier||Cruise Dates||Ship|
|CH3/75||4-13 March 1975||RRS Challenger|
|CH7A/75||1-6 May 1975||RRS Challenger|
|CH10A/75||4-10 July 1975||RRS Challenger|
|CH12A/75||26 August-2 September 1975||RRS Challenger|
|CH14A/75||7-12 November 1975||RRS Challenger|
|CH5A/76||29 March-5 April 1976||RRS Challenger|
|CH8/76||19 May-1 June 1976||RRS Challenger|
|CH12/76||4-15 August 1976||RRS Challenger|
|CH15/76||7-16 October 1976||RRS Challenger|
|CH17/76||7-20 December 1976||RRS Challenger|
|CH4/77||25 February-11 March 1977||RRS Challenger|
|CH6B/77||14-19 April 1977||RRS Challenger|
|CH10/77||29 June-10 July 1977||RRS Challenger|
|CH11/77||12-26 July 1977||RRS Challenger|
|CH13/77||20 August-3 September 1977||RRS Challenger|
|CH2/78||30 January-13 February 1978||RRS Challenger|
|CH6/78||11-21 April 1978||RRS Challenger|
|CH9/78||31 May-10 June 1978||RRS Challenger|
|CH11B/78||29 July-12 August 1978||RRS Challenger|
|CH11D/78||3-17 September 1978||RRS Challenger|
|CH14B/78||4-11 November 1978||RRS Challenger|
|CH7/79||10-23 May 1979||RRS Challenger|
|S5/79||19 June-2 July 1979||RRS Shackleton|
|CH13/79||11-16 September 1979||RRS Challenger|
|CH16/79||28 October-11 November 1979||RRS Challenger|
|CH4/80||26 February-7 March 1980||RRS Challenger|
|CH7/80||21 April-6 May 1980||RRS Challenger|
|CH2/81||26 January-4 February 1981||RRS Challenger|
|CH6A/81 CH6B/81||6-25 April 1981||RRS Challenger|
|CH10/81||4-14 July 1981||RRS Challenger|
|CH15/81||6-20 October 1981||RRS Challenger|
|CH7A/82 CH7B/82||26 April-16 May 1982||RRS Challenger|
|CH15/82||16-30 October 1982||RRS Challenger|
|CH7B/83||23 May-2 June 1983||RRS Challenger|
|CH11/83||10-24 August 1983||RRS Challenger|
|CH2/84||23 June-8 July 1984||RRS Challenger|
|CH10/84||16 November-6 December 1984||RRS Challenger|
|CH1/85||20 January-5 February 1985||RRS Challenger|
|CH4/85||2-16 May 1985||RRS Challenger|
|CH8/85||14-28 August 1985||RRS Challenger|
|CH9||8-22 January 1987||RRS Challenger|
|CH14||24 April-7 May 1987||RRS Challenger|
|CH22||23 November-5 December 1987||RRS Challenger|
|CH25||24 February-7 March 1988||RRS Challenger|
|CH30||6-23 June 1988||RRS Challenger|
|D180||20 January-4 February 1989||RRS Discovery|
|LF1/89||5-11 May 1989||RV Lough Foyle|
|LF2/89||4-10 August 1989||RV Lough Foyle|
|CD44||24 November-2 December 1989||RRS Charles Darwin|
|CH67A||21-29 June 1990||RRS Challenger|
|CH71A||29 August-5 September 1990||RRS Challenger|
|CH75B||23 February-3 March 1991||RRS Challenger|
|CH81||1-8 July 1991||RRS Challenger|
|CH97||25 September-6 October 1992||RRS Challenger|
|CH101B||13-20 March 1993||RRS Challenger|
|CH103||12-24 May 1993||RRS Challenger|
|CH105||3-16 September 1993||RRS Challenger|
|CH110||10-20 March 1994||RRS Challenger|
|CH112||28 April-13 May 1994||RRS Challenger|
|CH114||15-29 August 1994||RRS Challenger|
|CH116||17-29 November 1994||RRS Challenger|
|CD92B||13 April-2 May 1995||RRS Charles Darwin|
|CH120||18 July-6 August 1995||RRS Challenger|
|CH124||8-27 January 1996||RRS Challenger|
Other Cruises linked to this Fixed Station (with the number of series) - 0508S (29) 0700S (20) 0703S (20) CD176 (32) CD44 (34) CD92B (47) CH1/85 (19) CH10/77 (3) CH10/81 (21) CH10/84 (22) CH101B (13) CH103 (37) CH105 (34) CH10A/75 (15) CH11/77 (28) CH11/83 (35) CH110 (19) CH112 (35) CH114 (31) CH116 (25) CH11B/78 (26) CH11D/78 (14) CH120 (28) CH124 (32) CH12A/75 (3) CH13/77 (18) CH13/79 (17) CH14 (29) CH14A/75 (21) CH14B/78 (17) CH15/80 (8) CH15/81 (16) CH16/79 (13) CH2/78 (32) CH2/81 (13) CH2/82 (4) CH2/84 (29) CH22 (14) CH25 (18) CH3/83 (1) CH30 (23) CH4/77 (19) CH4/80 (29) CH4/85 (30) CH5A/76 (18) CH6/78 (25) CH63_2 (5) CH67A (27) CH6A/81 (14) CH6B/77 (24) CH6B/81 (20) CH7/79 (18) CH7/80 (16) CH71A (32) CH74A_1 (13) CH75B (31) CH7A/75 (24) CH7A/82 (24) CH7B/82 (13) CH7B/83 (29) CH8/76 (27) CH8/85 (30) CH81 (30) CH86B (8) CH89B (9) CH9 (25) CH9/78 (22) CH97 (30) CH9B/80 (10) D180 (30) D233 (10) D242 (23) D245 (25) D312 (34) D321B (35) D340A (34) D351 (34) DSK1/86 (10) FR13/85 (12) FR13/87 (2) FR14B/87 (2) FR18/87 (11) FR7B/86 (6) FR8/86 (13) LF1/89 (29) LF2/89 (30) PO300_2 (31) S5/79 (8)
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|