Metadata Report for BODC Series Reference Number 751972


Metadata Summary

Data Description

Data Category Currents -subsurface Eulerian
Instrument Type Acoustic doppler current profiler
Instrument Mounting research vessel
Originating Country United Kingdom
Originator -
Originating Organization National Oceanography Centre, Southampton
Processing Status QC in progress
Project(s) Oceans 2025
Oceans 2025 Theme 10
Oceans 2025 Theme 10 SO4
Oceans 2025 Theme 2
Oceans 2025 Theme 2 WP2.5
Oceans 2025 Theme 5
Oceans 2025 Theme 5 WP5.3
Oceans 2025 Theme 5 WP5.7
 

Data Identifiers

Originator's Identifier SUR32104
BODC Series Reference 751972
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 2007-07-28 11:05
End Time (yyyy-mm-dd hh:mm) 2007-07-29 11:05
Nominal Cycle Interval 300.0 seconds
 

Spatial Co-ordinates

Start Latitude 59.72367 N ( 59° 43.4' N )
End Latitude 59.96167 N ( 59° 57.7' N )
Start Longitude 18.75350 W ( 18° 45.2' W )
End Longitude 20.06717 W ( 20° 4.0' W )
Positional Uncertainty 0.0 to 0.01 n.miles
Minimum Sensor Depth 13.0 m
Maximum Sensor Depth 957.0 m
Minimum Sensor Height -
Maximum Sensor Height -
Sea Floor Depth -
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 -
 

Parameters

BODC CODE Rank Units Title
DBINAA01 0 Metres Depth below sea surface (ADCP bin)
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
ALATTR01 1 Degrees Latitude north (WGS84) by Trimble GPS
ALONTR01 1 Degrees Longitude east (WGS84) by Trimble GPS
APEWTR01 2 Centimetres per second Eastward velocity (over ground) of measurement platform by Trimble GPS
APNSTR01 2 Centimetres per second Northward velocity (over ground) of measurement platform by Trimble GPS
ASAMSP00 2 Decibels Signal return amplitude from the water body by shipborne acoustic doppler current profiler (ADCP) beam 1
ASAMSP02 2 Decibels Signal return amplitude from the water body by shipborne acoustic doppler current profiler (ADCP) beam 2
ASAMSP03 2 Decibels Signal return amplitude from the water body by shipborne acoustic doppler current profiler (ADCP) beam 3
ASAMSP04 2 Decibels Signal return amplitude from the water body by shipborne acoustic doppler current profiler (ADCP) beam 4
LCEWAS01 2 Centimetres per second Eastward current velocity (Eulerian) in the water body by shipborne acoustic doppler current profiler (ADCP)
LCNSAS01 2 Centimetres per second Northward current velocity (Eulerian) in the water body by shipborne acoustic doppler current profiler (ADCP)
LERRAS01 2 Centimetres per second Current velocity error in the water body by shipborne acoustic doppler current profiler (ADCP)
LREWAS01 2 Centimetres per second Eastward current velocity (relative to moving platform) in the water body by shipborne acoustic doppler current profiler (ADCP)
LRNSAS01 2 Centimetres per second Northward current velocity (relative to moving platform) in the water body by shipborne acoustic doppler current profiler (ADCP)
LRZAAS01 2 Centimetres per second Upward current velocity 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

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

No Narrative Document information held in the BODC database


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/


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


Oceans 2025 Theme 2, Work Package 2.5: Physical Processes and the Supply of Nutrients to the Euphotic Zone

The emphasis behind this Work Package is to gain a better understanding of the ocean's biological carbon pump (OBP), an important process in the global carbon cycle. Small changes in its magnitude resulting from climate change could have significant effects, both on the ocean's ability to sequester CO2 and on the natural flux of marine carbon. This work package is concerned with the effect of physical processes and circulation on nutrient supply to the euphotic zone. Many physical pathways influence nutrient supply, such as winter overturning, Ekman pumping, small-scale turbulent mixing and mesoscale ageostrophic circulations, (of which, eddy pumping is but one example). Increased stratification will change patterns of winter overturning and dampen small-scale mixing. Shifts in wind patterns will perturb Ekman pumping. Changes in gradients of ocean heating and wind-forcing will alter the distribution of potential energy released through baroclinic instability of eddies and fronts. The combined effect of change on total nutrient supply will therefore be complex. Such physically-mediated changes, coupled to changes in aeolian dust deposition, may profoundly alter upper ocean plankton communities, biogeochemical cycling and carbon export.

This Work Package will be primarily coordinated by the National Oceanography Centre, Southampton (NOC). Specific objectives are:

Aspects of this work will link to Oceans 2025 Theme 9 and 10, and Theme 2 WP 2.6.

More detailed information on this Work Package is available from pages 13-15 of the official Oceans 2025 Theme 2 document: Oceans 2025 Theme 2

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


Oceans 2025 Theme 5: Continental Margins and the Deep Ocean

The deep ocean and the seafloor beneath it are the largest yet least known environments on our planet. They profoundly influence the way in which the Earth reacts to climate change, provide vital resources, and can cause natural catastrophes (with significant risks to the UK). A better understanding of the biodiversity and resource potential of the deep ocean, its geophysics and its complex interactions with the global carbon cycle are all urgently required.

The overall aim of Theme 5 is to deliver coordinated, multidisciplinary research on the functioning of the deep ocean from the photic zone to the sub-seabed, encompassing biology, physics, geology, chemistry and mathematical modelling. Such an integrated deep-sea programme is unique in the UK and will ensure the provision of knowledge essential for underpinning UK policy in conserving marine biodiversity, controlling the effects of global change, managing ocean resources in a sustainable manner, and mitigating the effects of geohazards.

The specific objectives of Theme 5 are:

Theme 5 combines two Research Units, on Continental Margins and on the Biochemistry of the Deep Ocean. Ultimately the science of the two activities will be combined, but because the methods of study and the resources needed are largely different, the work has been planned within two groups.

In Continental Margins, the physical processes regulating the transport of sediment is investigated as well as the transport of hydrocarbons and aqueous fluids from the seafloor. The effect of both of these major processes on the landscape ecology of the continental slope will be assessed. In addition, the causes, mechanisms and frequency of submarine geohazards will be studied, particularly those that potentially could have a devastating effect on coastal communities, such as earthquake and landslide-induced tsunamis. Carbon flux from the geosphere into the ocean will be assessed. The information will be used to advise on whole ecosystem management strategies, including policy issues relating to Marine Protected Areas and international treaties on the development of open ocean resources.

In Biogeochemistry of the Deep Ocean, the flux of particles through the 'twilight zone' in order to reduce the large uncertainties in our knowledge of the magnitude of the downward flux in various biogeochemical provinces of the global ocean will be studied. The twilight zone is a large biogeochemical reactor influencing the supply of nutrients to the euphotic zone and the fate of materials consigned to the deep seafloor. Theme 5 will study how zooplankton and microbes repackage and breakdown particles, and how these processes influence carbon transfer. Direct observations and experimental approaches will provide data to drive stoichiometric models of heterotrophic OM utilisation. The impact on the deep-sea benthos of repackaged OM, and the of part of surface production that by-passes twilight zone processes, will be assessed by analysing global patterns and through ROV in situ experimentation. Proven modelling expertise in upper ocean systems will be extended to benthic ecosystems utilising the information generated by bentho-pelagic coupling observations and experimental approaches.

The official Oceans 2025 documentation for this Theme is available from the following link: Oceans 2025 Theme 5

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


Oceans 2025 Theme 5, Work Package 5.3: Physical processes regulating the transport of sediments to the deep ocean

Sediment sequences on continental margins hold a record of the processes which deposited them, including gravity flows, along-slope transport by oceanographic currents and settling of pelagic material. Deciphering this record can help us understand the relative importance of the various processes, many of which are episodic (and almost impossible to study as they happen) yet of fundamental significance to the sustainable use of continental margins. That is because they influence the distribution of benthic ecosystems, redistribute carbon and pollutants from the land and shelf seas to the deep ocean, and give insights into the formation of buried sedimentary rocks such as those that form hydrocarbon reservoirs. This WP focuses on the physical processes controlling sediment transport through canyons, and gravity flows and their deposits. It builds on current work funded by the EU HERMES project and industry sponsors, and will use information on modern sediment deposits to increase our understanding of the structure of hydrocarbon reservoirs.

More detailed information on this WP is available on pages 8-9 of the official Oceans 2025 Theme 5 document:Oceans 2025 Theme 5

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


Oceans 2025 Theme 5, Work Package 5.7: Twilight zone dynamics

The surface ocean has been partitioned into discrete functional provinces with particular biogeochemical characteristics. In the Atlantic between 50° N and 50° S, Longhurst (1998) identified six provinces based on physical forcing and primary production. Links between these contrasting production regimes and the underlying deep ocean have not been studied in any detail. Some conceptual approaches, e.g. the bifurcation model, show how surface water production might relate to export, but this is complicated by evidence for strong decoupling between the magnitude of production and particulate export.

Physical dynamics of twilight zone (TZ). We will combine the latest technology and observational techniques to tackle the physically driven pathways to, from and through the deep ocean. On transects, we will test the hypotheses that the TZ is dominated by 3D eddy transports stirring the TZ and exchanging water across the permanent thermocline, while below there is a more quiescent weakly stratified environment dominated by slow mode barotropic flows, interrupted by topographic features over which increased velocity shear leads to enhanced diffusive mixing.

Particle flux through the twilight zone. Our understanding of deep ocean biogeochemistry, community structure and function can be improved by reducing uncertainties in the magnitude of downward flux, and how this changes with depth, region and time. In addition to carbon, this improved understanding must include all limiting elements and the wide variety of complex organic molecules that support life in the deep ocean. Large uncertainties in published data make such quantification a major challenge.

Twilight zone biogeochemistry. For comparison with the microbial community, we will address the role of zooplankton in the TZ by measuring biomass and size spectra using a video plankton camera system and laser optical plankton counter, verified with physical samples from closing nets. Community energy demand will be estimated from the size spectra and allometric relationships to quantify the role of zooplankton in TZ C flux.

Modelling the twilight zone system. For the TZ zone, our modelling approach will focus on particles and their utilisation by zooplankton and bacteria, and on comparing model output with data. Particulate OM will be divided into size classes corresponding to the size spectra of sinking particles, which has consequences for their depth penetration into the ocean. Production and consumption of dissolved OM will also be represented. Both C and N will be included as model currencies, using appropriate stoichiometric models of heterotrophic OM utilisation. Ecosystem models will be tested and analysed in 1D using ecosystem testbeds (Theme 9). The most appropriate will then be used in 3D using the Harvard Ocean Prediction System model, focussed on the fine-scale survey work proposed around the PAP site. Pelagic biology, which provides the export flux, will be developed in this model as part of Theme 2 then extended to the TZ to determine the relationship between TZ processes and variability in the euphotic zone. Climate sensitivity (wind forcing, heating) tests will also be undertaken to examine their impact on export.

More detailed information on this WP is available on page 14-16 of the official Oceans 2025 Theme 5 document: Oceans 2025 Theme 5

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

References:

Longhurst, A.R. (1998) Ecological Geography of the Sea, Academic Press, 398pp


Data Activity or Cruise Information

Cruise

Cruise Name D321 (D321A)
Departure Date 2007-07-24
Arrival Date 2007-08-23
Principal Scientist(s)John T Allen (National Oceanography Centre, Southampton)
Ship RRS Discovery

Complete Cruise Metadata Report is available here


Fixed Station Information

Fixed Station Information

Station NameExtended Ellett Line
CategoryOffshore route/traverse

Extended Ellett Line

The Extended Ellett Line is a hydrographic transect consisting of 58 individual fixed stations which have been occupied, typically on an annual basis, since September 1996. The Line runs from the south of Iceland, across the Iceland Basin to the outcrop of Rockall, and across the Rockall Trough to the north west coast of Scotland (see map). CTD dips and associated water sampling for the analysis of nutrients are routinely performed during each station occupation.

The Extended Ellett Line augments the original Ellett Line time series - a shorter repeated transect which encompassed those stations between Rockall and Scotland. Work on the Ellett Line was typically carried out at least once a year between 1975 and 1996.

Map of standard stations (1996-present)

BODC image

Map produced using the GEBCO Digital Atlas

The white triangles indicate the nominal positions of the Extended Ellett Line stations visited since September 1996. Measurements made along the Extended Ellett Line lie within a box bounded by co-ordinates 56° N, 21° W at the south west corner and 65° N, 6° W at the north east corner.

Nominal Extended Ellett Line stations (September 1996-present)

Listed below are nominal details of the standard hydrographic stations that have formed the Extended Ellett Line since September 1996.

Station Latitude Longitude Depth Range
IB23S 63.318 N 20.210 W 125 m -
IB22S 63.217 N 20.067 W 660 m 0.0 nm
IB21S 63.133 N 19.917 W 1030 m 6.5 nm
IB20S 62.917 N 19.550 W 1415 m 16.4 nm
IB19S 62.667 N 19.667 W 1500 m 16.0 nm
IB18S 62.333 N 19.833 W 1800 m 16.0 nm
IB17 62.000 N 20.000 W 1700 m 20.6 nm
IB16 61.500 N 20.000 W 2000 m 30.1 nm
IB15 61.250 N 20.000 W 2375 m 15.0 nm
IB14 61.000 N 20.000 W 2400 m 15.0 nm
IB13 60.500 N 20.000 W 2500 m 30.1 nm
IB12 60.000 N 20.000 W 2700 m 30.1 nm
IB11 59.667 N 19.117 W 2680 m 33.3 nm
IB10 59.400 N 18.417 W 2420 m 26.7 nm
IB9 59.333 N 18.233 W 1910 m 6.9 nm
IB8 59.200 N 17.883 W 1540 m 13.4 nm
IB7 59.117 N 17.667 W 1000 m 8.3 nm
IB6 58.950 N 17.183 W 850 m 18.0 nm
IB5 58.883 N 17.000 W 1150 m 7.0 nm
IB4 58.500 N 16.000 W 1210 m 38.8 nm
IB3 58.250 N 15.333 W 680 m 25.8 nm
IB2 57.950 N 14.583 W 480 m 29.9 nm
IB1 57.667 N 13.900 W 160 m 27.7 nm
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

Occupations of the Extended Ellett Line (September 1996-present)

BODC Cruise Identifier Cruise Dates Ship
D223A 28 September-21 October 1996 RRS Discovery
D230 7 August-17 September 1997 RRS Discovery
D233 23 April-1 June 1998 RRS Discovery
D242 7 September-6 October 1999 RRS Discovery
D245 * 27 January-20 February 2000 RRS Discovery
0700S * 8-22 May 2000 FRV Scotia
D253 4 May-20 June 2001 RRS Discovery
0703S * 15 April-5 May 2003 FRV Scotia
PO300_2 * 19 July-6 August 2003 RRS Poseidon
PO314 11 July-23 July 2004 RV Poseidon
CD176 6 October-1 November 2005 RRS Charles Darwin
D312 11-31 October 2006 RRS Discovery
D321A 24 July-23 August 2007 RRS Discovery
D321B 24 August-9 September 2007 RRS Discovery
0508S * 6-25 May 2008 FRV Scotia
D340A 10-25 June 2009 RRS Discovery
D351 10-28 May 2010 RRS Discovery
D365 13 May-02 June 2011 RRS Discovery

* These cruises only surveyed the original hydrographic section between Scotland and Rockall.

Other Series linked to this Fixed Station for this cruise - 751960 753573 753585 756478 771438 771451 771487 772245 772257 772269 1043415

Other Cruises linked to this Fixed Station (with the number of series) - 0508S (29) 0700S (20) 0703S (20) CD176 (40) D233 (25) D242 (45) D245 (25) D312 (51) D321 (D321A) (11) D321B (59) D340A (58) D351 (23) PO300_2 (31)


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