Metadata Report for BODC Series Reference Number 1015776
Metadata Summary
Problem Reports
Data Access Policy
Narrative Documents
Project Information
Data Activity or Cruise Information
Fixed Station Information
BODC Quality Flags
Metadata Summary
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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
Aanderaa Recording Current Meter Model 9/11
The RCM 9/11 is a family of single-point Doppler recording current meters with different casing options to allow working at depths of up to 300 (RCM 9 LW), 2000 (RCM 9 IW) or 6000 (RCM 11) metres. The recording unit is 51.3 cm or 59.5 cm high (RCM 9 and RCM 11, respectively) with a diameter of 12.8 cm.
The RCM is most commonly deployed in an in-line mooring configuration. As it operates under a tilt up to 35° from vertical, it has a variety of in-line mooring applications by use of surface buoy or sub surface buoy. The instrument is installed in a mooring frame that allows easy installation and removal of the instrument without disassembly of the mooring line. The instrument can also be used for direct reading of the various parameters. This is conveniently done due to its compact design, low drag force and easy handling. Data can be stored internally and read after retrieval or be read in real time on deck by use of the profiling cable.
Meter comprises:
- A Vane Plate (3681) to stabilise the meter during profiling (stops spin).
- Stainless Steel Mooring Frame made to facilitate easy installation and removal of the instrument by use of two knobs.
- Doppler Current Sensor (Current speed sensor) - Range of speed recorded 0-300 cm s-1 with a 0.3 cm s-1 resolution.
- Hall Effect Compass - Direction recorded with 0.35 ° resolution, 5 ° for 0.15 ° tilt and 7.5 ° for 15-35 ° tilt.
- Thermistor (Temperature sensor) - With selectable wide, low, high and Arctic ranges. Standard range -2.70 to 21.77 °C, accuracy 0.05 °C, resolution 0.1% of selected range, 63% response time (12 sec).
- Inductive Cell Conductivity Sensor (optional) - Range 0 to 75 mS cm-1, standard resolution 0.002 mS cm-1.
- Pressure Sensor (optional) - Silicon piezoresistive bridge, standard range 0 to 3500 kPa, resolution 0.1% of range.
- Turbidity Sensor (optional) - Optical back-scatter sensor, resolution 0.1% of full scale, (RCM 11 depth capacity 2000 m).
- Oxygen Sensor (optional) - Oxygen optode, range 0 to 500 µM, resolution < 1µM, response time 60 sec, depth capacity 6000 m.
- Data storage units DSU 2990 and 2990E are standard data storage devices for Aanderaa data collecting instruments.
A built-in quartz clock allows the time of the first measurement to be recorded in the DSU. The measuring system is made up of a self-balancing bridge with sequential measurement of 10 channels and solid state memory. Channel 1 is a fixed reference reading for control purposes and data identification. Channels 2 and 3 represent measurement of current speed and direction. The direction is found by the use of measurements along two orthogonal axis and linking them to true north by use of an internal compass reading. The instrument can operate continuously or in eight intervals from 1 to 120 minutes. At 60-minute recording interval the operating time is more than two years. The current speed and direction are averaged over the measuring interval. Channels 4, 5 and 6 represent temperature, conductivity and pressure respectively.
Further information can be found in the manufacturer's instrument specification.
RAPIDMOC/MOCHA Current Meter data processing document
This document outlines the procedures undertaken to process and quality assure current meter data collected under the RAPIDMOC and MOCHA projects.
Originator's processing
The raw data are downloaded from the instrument and converted to ASCII format.
Once in ASCII format the data are corrected for the following -
- Speed bias (caused by the mooring motion)
- Sound speed (as electromagnetic current meter sensors use the speed of sound in water to calculate the doppler shift in the returned signal, they are corrected for variations in sound speed using temperature data as sound speed varies with temperature).
- Magnetic variation
A 40 hour low pass filter is also applied to the data.
Calculating and applying calibrations
Manufacturers calibrations are applied.
Quality Control
Data were visually inspected for out-lying data and instrument electrical spikes removed.
BODC processing
Data are received after quality checks have been made and calibrations have been applied. The data files are submitted in ASCII format as one file per instrument.
Once the submitted data files are safely archived, the data undergo reformatting and banking procedures:
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The data files are transferred into a common format, a NetCDF subset.
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Standard parameter codes are assigned that accurately describe the data (see Parameter mapping section below).
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Unit conversions are applied, if necessary, so that units are standardised (see Parameter mapping section below).
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The data are screened visually and any spikes or instrument malfunctions can be clearly labelled with quality control flags.
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Comprehensive documentation is prepared describing the collection, processing and quality of each data series.
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Detailed metadata and documents are loaded to the database and linked to each series so that the information is readily available to future users.
Parameter mapping
The following describes the parameters contained in the originator's files and their mapping to BODC parameter codes:
| Identifier | Unit | Definition | BODC parameter code | Units | Unit conversion | Comments |
|---|---|---|---|---|---|---|
| YY | year | Year | AADYAA01 | days | - | Combined with MM and DD to form a date and transferred |
| MM | month | Month | AADYAA01 | days | - | Combined with MM and DD to form a date and transferred |
| DD | day | Day | AADYAA01 | days | - | Combined with MM and DD to form a date and transferred |
| HH | hour | Decimal hours | AAFDZZ01 | days | /24 | Transferred |
| T | °C | Temperature | TEMPPR01 | °C | - | Transferred |
| P | dbar | Pressure | PRSTPR01 | dbar | - | Transferred |
| U | cm/s | Eastward velocity | LCEWEL01 | cm/s | - | Transferred |
| V | cm/s | Northward velocity | LCNSEL01 | cm/s | - | Transferred |
Project Information
Rapid Climate Change (RAPID) Programme
Rapid Climate Change (RAPID) is a £20 million, six-year (2001-2007) programme of the Natural Environment Research Council (NERC). The programme aims to improve our ability to quantify the probability and magnitude of future rapid change in climate, with a main (but not exclusive) focus on the role of the Atlantic Ocean's Thermohaline Circulation.
Scientific Objectives
- To establish a pre-operational prototype system to continuously observe the strength and structure of the Atlantic Meridional Overturning Circulation (MOC).
- To support long-term direct observations of water, heat, salt, and ice transports at critical locations in the northern North Atlantic, to quantify the atmospheric and other (e.g. river run-off, ice sheet discharge) forcing of these transports, and to perform process studies of ocean mixing at northern high latitudes.
- To construct well-calibrated and time-resolved palaeo data records of past climate change, including error estimates, with a particular emphasis on the quantification of the timing and magnitude of rapid change at annual to centennial time-scales.
- To develop and use high-resolution physical models to synthesise observational data.
- To apply a hierarchy of modelling approaches to understand the processes that connect changes in ocean convection and its atmospheric forcing to the large-scale transports relevant to the modulation of climate.
- To understand, using model experimentation and data (palaeo and present day), the atmosphere's response to large changes in Atlantic northward heat transport, in particular changes in storm tracks, storm frequency, storm strengths, and energy and moisture transports.
- To use both instrumental and palaeo data for the quantitative testing of models' abilities to reproduce climate variability and rapid changes on annual to centennial time-scales. To explore the extent to which these data can provide direct information about the thermohaline circulation (THC) and other possible rapid changes in the climate system and their impact.
- To quantify the probability and magnitude of potential future rapid climate change, and the uncertainties in these estimates.
Projects
Overall 38 projects have been funded by the RAPID programme. These include 4 which focus on Monitoring the Meridional Overturning Circulation (MOC), and 5 international projects jointly funded by the Netherlands Organisation for Scientific Research, the Research Council of Norway and NERC.
The RAPID effort to design a system to continuously monitor the strength and structure of the North Atlantic Meridional Overturning Circulation is being matched by comparative funding from the US National Science Foundation (NSF) for collaborative projects reviewed jointly with the NERC proposals. Three projects were funded by NSF.
A proportion of RAPID funding as been made available for Small and Medium Sized Enterprises (SMEs) as part of NERC's Small Business Research Initiative (SBRI). The SBRI aims to stimulate innovation in the economy by encouraging more high-tech small firms to start up or to develop new research capacities. As a result 4 projects have been funded.
Monitoring the Meridional Overturning Circulation at 26.5N (RAPIDMOC)
Scientific Rationale
There is a northward transport of heat throughout the Atlantic, reaching a maximum of 1.3PW (25% of the global heat flux) around 24.5°N. The heat transport is a balance of the northward flux of a warm Gulf Stream, and a southward flux of cooler thermocline and cold North Atlantic Deep Water that is known as the meridional overturning circulation (MOC). As a consequence of the MOC northwest Europe enjoys a mild climate for its latitude: however abrupt rearrangement of the Atlantic Circulation has been shown in climate models and in palaeoclimate records to be responsible for a cooling of European climate of between 5-10°C. A principal objective of the RAPID programme is the development of a pre-operational prototype system that will continuously observe the strength and structure of the MOC. An initiative has been formed to fulfill this objective and consists of three interlinked projects:
- A mooring array spanning the Atlantic at 26.5°N to measure the southward branch of the MOC (Hirschi et al., 2003 and Baehr et al., 2004).
- Additional moorings deployed in the western boundary along 26.5°N (by Prof. Bill Johns, University of Miami) to resolve transport in the Deep Western Boundary Current (Bryden et al., 2005). These moorings allow surface-to-bottom density profiles along the western boundary, Mid-Atlantic Ridge, and eastern boundary to be observed. As a result, the transatlantic pressure gradient can be continuously measured.
- Monitoring of the northward branch of the MOC using submarine telephone cables in the Florida Straits (Baringer et al., 2001) led by Dr Molly Baringer (NOAA/AOML/PHOD).
The entire monitoring array system created by the three projects will be recovered and redeployed annually until 2008 under RAPID funding. From 2008 until 2014 the array will continue to be serviced annually under RAPID-WATCH funding.
The array will be focussed on three regions, the Eastern Boundary (EB), the Mid Atlantic Ridge (MAR) and the Western Boundary (WB). The geographical extent of these regions are as follows:
- Eastern Boundary (EB) array defined as a box with the south-east corner at 23.5°N, 25.5°W and the north-west corner at 29.0°N, 12.0°W
- Mid Atlantic Ridge (MAR) array defined as a box with the south-east corner at 23.0°N, 52.1°W and the north-west corner at 26.5°N, 40.0°W
- Western Boundary (WB) array defined as a box with the south-east corner at 26.0°N, 77.5°W and the north-west corner at 27.5°N, 69.5°W
References
Baehr, J., Hirschi, J., Beismann, J.O. and Marotzke, J. (2004) Monitoring the meridional overturning circulation in the North Atlantic: A model-based array design study. Journal of Marine Research, Volume 62, No 3, pp 283-312.
Baringer, M.O'N. and Larsen, J.C. (2001) Sixteen years of Florida Current transport at 27N Geophysical Research Letters, Volume 28, No 16, pp3179-3182
Bryden, H.L., Johns, W.E. and Saunders, P.M. (2005) Deep Western Boundary Current East of Abaco: Mean structure and transport. Journal of Marine Research, Volume 63, No 1, pp 35-57.
Hirschi, J., Baehr, J., Marotzke J., Stark J., Cunningham S.A. and Beismann J.O. (2003) A monitoring design for the Atlantic meridional overturning circulation. Geophysical Research Letters, Volume 30, No 7, article number 1413 (DOI 10.1029/2002GL016776)
RAPID- Will the Atlantic Thermohaline Circulation Halt? (RAPID-WATCH)
RAPID-WATCH (2007-2014) is a continuation programme of the Natural Environment Research Council's (NERC) Rapid Climate Change (RAPID) programme. It aims to deliver a robust and scientifically credible assessment of the risk to the climate of UK and Europe arising from a rapid change in the Atlantic Meridional Overturning Circulation (MOC). The programme will also assess the need for a long-term observing system that could detect major MOC changes, narrow uncertainty in projections of future change, and possibly be the start of an 'early warning' prediction system.
The effort to design a system to continuously monitor the strength and structure of the North Atlantic MOC is being matched by comparative funding from the US National Science Foundation (NSF) for the existing collaborations started during RAPID for the observational arrays.
Scientific Objectives
- To deliver a decade-long time series (2004-2014) of calibrated and quality-controlled measurements of the Atlantic MOC from the RAPID-WATCH arrays.
- To exploit the data from the RAPID-WATCH arrays and elsewhere to determine and interpret recent changes in the Atlantic MOC, assess the risk of rapid climate change, and investigate the potential for predictions of the MOC and its impacts on climate.
This work will be carried out in collaboration with the Hadley Centre in the UK and through international partnerships.
Mooring Arrays
The RAPID-WATCH arrays are the existing 26°N MOC observing system array (RAPIDMOC) and the WAVE array that monitors the Deep Western Boundary Current. The data from these arrays will work towards meeting the first scientific objective.
The RAPIDMOC array consists of moorings focused in three geographical regions (sub-arrays) along 26.5° N: Eastern Boundary, Mid-Atlantic Ridge and Western Boundary. The Western Boundary sub-array has moorings managed by both the UK and US scientists. The other sub-arrays are solely led by the UK scientists. The lead PI is Dr Stuart Cunningham of the National Oceanography Centre, Southampton, UK.
The WAVE array consists of one line of moorings off Halifax, Nova Scotia. The line will be serviced in partnership with the Bedford Institute of Oceanography (BIO), Halifax, Canada. The lead PI is Dr Chris Hughes of the Proudman Oceanographic Laboratory, Liverpool, UK.
All arrays will be serviced (recovered and redeployed) either on an annual or biennial basis using Research Vessels from the UK, US and Canada.
Modelling Projects
The second scientific objective will be addressed through numerical modelling studies designed to answer four questions:
- How can we exploit data from the RAPID-WATCH arrays to obtain estimates of the MOC and related variables?
- What do the observations from the RAPID-WATCH arrays and other sources tell us about the nature and causes of recent changes in the Atlantic Ocean?
- What are the implications of RAPID-WATCH array data and other recent observations for estimates of the risk due to rapid change in the MOC?
- Could we use RAPID-WATCH and other observations to help predict future changes in the MOC and climate?
Data Activity or Cruise Information
Data Activity
| Start Date (yyyy-mm-dd) | 2009-04-30 |
| End Date (yyyy-mm-dd) | 2010-04-02 |
| Organization Undertaking Activity | National Oceanography Centre, Southampton |
| Country of Organization | United Kingdom |
| Originator's Data Activity Identifier | WB1#6 |
| Platform Category | subsurface mooring |
RAPID Moored Instrument Rig WB1#6
This rig was deployed as part of the Western Boundary (WB) array of the RAPIDMOC project.
| Deployment cruise | RV Ronald H. Brown cruise RB0901 |
|---|---|
| Recovery cruise | RV Oceanus cruise OC459-1 |
The rig was anchored by a 1800 kg chain and was kept erect by a large sub-surface float supplemented by groups of smaller buoyancy all attached on swivels.
Instruments deployed on the rig
| Depth | Instrument |
|---|---|
| 50 m | Sea-Bird SBE37 SMP MicroCAT (#3206) |
| 100 m | Aanderaa RCM11 current meter (#381) |
| 100 m | Sea-Bird SBE37 SMP MicroCAT (#3219) |
| 175 m | Sea-Bird SBE37 SMP MicroCAT (#6837) |
| 250 m | Sea-Bird SBE37 SMP MicroCAT (#6838) |
| 325 m | Sea-Bird SBE37 SMP MicroCAT (#6839) |
| 400 m | Aanderaa RCM11 current meter (#383) |
| 400 m | Sea-Bird SBE37 SMP MicroCAT (#6840) |
| 500 m | Sea-Bird SBE37 SMP MicroCAT (#6841) |
| 600 m | Sea-Bird SBE37 SMP MicroCAT (#3209) |
| 700 m | Sea-Bird SBE37 SMP MicroCAT (#3215) |
| 814 m | Aanderaa RCM11 current meter (#395) |
| 815 m | Sea-Bird SBE37 SMP MicroCAT (#3216) |
| 900 m | Sea-Bird SBE37 SMP MicroCAT (#3221) |
| 1000 m | Sea-Bird SBE37 SMP MicroCAT (#3224) |
| 1100 m | Sea-Bird SBE37 SMP MicroCAT (#3225) |
| 1224 m | Aanderaa RCM11 current meter (#399) |
| 1224 m | Sea-Bird SBE37 SMP MicroCAT (#3234) |
| 1350 m | Sea-Bird SBE37 SMP MicroCAT (#3222) |
Instrument Aanderaa RCM11 current meter #381 recorded no data whilst deployed. Instrument Aanderaa RCM11 current meter #383 data could not be downloaded from the instrument, hence no data are available.
Other Series linked to this Data Activity - 1091860 1091927 1091884 1091964 1091823 1091835 1091872 1015764 1091847 1091859 1091896 1091940 1091903 1091915 1091939 1091952
Cruise
| Cruise Name | RB0901 |
| Departure Date | 2009-04-15 |
| Arrival Date | 2009-05-05 |
| Principal Scientist(s) | Christopher S Meinen (NOAA Atlantic Oceanographic and Meteorological Laboratory) |
| Ship | NOAA Ship Ronald H. Brown |
Complete Cruise Metadata Report is available here
Fixed Station Information
Fixed Station Information
| Station Name | Western Boundary Array |
| Category | Offshore area |
| Latitude | 26° 37.50' N |
| Longitude | 73° 37.50' W |
| Water depth below MSL |
RAPIDMOC Western Boundary (WB) Array
The Western Boundary Array defines a box in which moorings were deployed at the western side of the North Atlantic as part of the RAPIDMOC project and the collaborative project Meridional Overturning Circulation and Heatflux Array (MOCHA). The box region has latitudinal limits of 26° N to 27.5° N and longitudinal limits of 69.5° W to 77.5° W. Moorings have occupied this region since 2004 and are typically deployed for 6 to 18 months.
Moored data summary
| Year | Cruise ID | Number of moorings | Data types (number of instruments) |
|---|---|---|---|
| 2004 | D278 | 9 (6 RAPIDMOC, 3 MOCHA) | ADCP (2), BPR (8), CM (29), MCTD (52), MMP (1) |
| 2005 | KN182_2 | 11 (6 RAPIDMOC, 5 MOCHA) | ADCP (2), BPR (6), CM (27), MCTD (56) |
| 2006 | RB06-02, SJ14-06 | 11 (6 RAPIDMOC, 5 MOCHA) | ADCP (1), BPR (3), CM (22), IES (7), MCTD (60) |
| 2007 | RB07-01 | 7 (7 RAPIDMOC) | ADCP (1), BPR (4), CM (16), MCTD (47) |
| 2008 | SJ08-03 | 11 (8 RAPIDMOC, 3 MOCHA) | ADCP (2), BPR (3), CM (40), MCTD (80) |
| 2009 | RB0901, D344, D345 | 16 (11 RAPIDMOC, 5 MOCHA) | ADCP (2), BPR (5), CM (39), MCTD (91), DVS (1) |
| 2010 | OC459-1, RB1009 | 9 (8 RAPIDMOC, 1 MOCHA) | ADCP (1), BPR (7), CM (23), MCTD (54) |
| 2011 | KN200-4 | 7 (7 RAPIDMOC, 6 MOCHA) | ADCP (2), BPR (7), CM (43), MCTD (86), DVS (1), IES (1) |
Cruise data summary
During the cruises to service the moored array, a variety of data types are collected. The table below is a summary of these data. The number of CTD profiles performed on these cruises within the box region defined above is also included. Trans-Atlantic hydrographic CTD sections have also been performed since 2004 and are included in the table.
| Cruise ID | Cruise description | Data types | Number of CTD profiles performed within the box region |
|---|---|---|---|
| D277 | Initial array deployment | DIS, MET, NAV, SADCP, SURF | 1 |
| D278 | Initial array deployment | DIS, MET, NAV, SADCP, SURF | 16 |
| D279 | Hydrographic section | CTD, DIS, LADCP, MET, NAV, SADCP, SURF | 31 |
| KN182_2 | Array service | CTD, DIS, MET, NAV, SADCP, SURF | 64 |
| RB0601 | Array service | CTD, DIS, LADCP, MET, NAV, SADCP, SURF | 39 |
| SJ14-06 | Array service | CTD, DIS, LADCP, MET, NAV, SADCP, SURF | 33 |
| RB07-01 | Array service | CTD, DIS, LADCP, MET, NAV, SADCP, SURF | 36 |
| SJ08-03 | Array service | CTD, DIS, LADCP, MET, NAV, SADCP, SURF | 33 |
| RB0901 | Array service | CTD, DIS, LADCP, MET, NAV, SADCP, SURF | 35 |
| D344 | Array service | CTD, DIS, MET, NAV, SADCP, SURF | 3 |
| D345 | Array service | CTD, DIS, LADCP, MET, NAV, SADCP, SURF | 24 |
| OC459-1 | Array service | CTD, DIS, MET, NAV, SADCP, SURF | 9 |
| OC459-2 | Western Boundary Hydrographic section | CTD, DIS, LADCP, MET, NAV, SADCP, SURF | 27 |
| D346 | Hydrographic section | CTD, DIS, LADCP, MET, NAV, SADCP, SURF | 31 |
| RB1009 | WB4 service | CTD, MET, SURF, NAV | 2 |
| KN200-4 | Array service | CTD, DIS, MET, NAV, SURF | 34 |
Data type ID and description
| Data type ID | Description |
|---|---|
| ADCP | Acoustic Doppler Current Profiler |
| BATH | Bathymetry |
| BPR | Bottom Pressure Recorder |
| CM | Current Meter |
| CTD | Conductivity-Temperature-Depth profiler |
| DIS | Discrete water bottle samples |
| DVS | Doppler Volume sampler |
| IES | Inverted Echo Sounder |
| LADCP | Lowered Acoustic Doppler Current Profiler |
| MET | Meteorology |
| MCTD | Moored Conductivity-Temperature-Depth sensor |
| MMP | McLane Moored Profiler - profiling CTD and current meter |
| NAV | Navigation |
| SADCP | Shipborne Acoustic Doppler Current Profiler |
| SURF | Sea surface data |
Other Series linked to this Fixed Station for this cruise - 946093 973816 973828 973841 973853 973865 1015647 1015764 1015868 1015881 1015893 1015900 1015912 1015924 1015936 1016000 1016012 1016024 1016036 1091823 1091835 1091847 1091859 1091860 1091872 1091884 1091896 1091903 1091915 1091927 1091939 1091940 1091952 1091964 1091976 1091988 1092003 1092015 1092027 1092039 1092040 1092052 1092064 1092076 1092088 1092107 1092119 1092120 1092132 1092144 1092156 1092168 1092181 1092193 1092200 1092212 1092224 1092236 1092248 1092261 1092273 1092285 1092297 1092304 1092316 1092328 1092341 1092353 1097542 1097554 1097566 1097578 1097591 1097609
Other Cruises linked to this Fixed Station (with the number of series) - D278 (90) D344 (8) D345 (41) D346 (31) KN182_2 (85) KN200-4 (86) OC459-1 (56) RB0602 (42) RB0701 (58) RB0901 (74) RB1009 (24) RB1201 (55) SJ-08-03 Leg 1 (37) SJ-08-03 Leg 2 (75) SJ-14-06 (62)
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 |
