Metadata Report for BODC Series Reference Number 2228836

• Metadata Summary

• Problem Reports

• Data Access Policy

• Narrative Documents

• Project Information

• Data Activity or Cruise Information

• Fixed Station Information

• BODC Quality Flags

• SeaDataNet Quality Flags

Metadata Summary

Problem Reports

No Problem Report Found in the Database

Data Access Policy

Open 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.

If the Information Provider does not provide a specific attribution statement, or if you are using Information from several Information Providers and multiple attributions are not practical in your product or application, you may consider using the following:

"Contains public sector information licensed under the Open Government Licence v1.0."

Narrative Documents

Teledyne RDI Workhorse Sentinel 600 kHz Acoustic Doppler Current Profiler (ADCP)

The Workhorse Sentinel is a self-contained ADCP that can be used either on a mooring or mounted in the hull of a moving vessel. Its 4-beam design provides a redundant data source (in case of a blocked or damaged beam), an independent data quality measure (error velocity) and reduces the variance in data, thereby improving data reliability, quality and accuracy.

Real-time data can be transmitted to shore via a cable link or acoustic modem or they can be stored internally. Sensors for bottom tracking, pressure and directional wave measurements can be added to the instrument and a special casing is available for deeper applications.

Specifications

Further details can be found in the manufacturer's specification sheet.

Processing by BODC of moored acoustic doppler current profiler (ADCP) from cruise DY120 using Teledyne RDI Sentinel Workhorse 600kHz

DY120 Teledyne RDI Sentinel Workhorse 600kH data were submitted in file format .txt, and were converted to QXF (BODC internal NetCDF). Due to large size of data file, data was split into 3 series by calendar year. The instrument was powered on prior to deployment, and the data was trimmed to remove the period before the mooring had fully settled on the seabed.

Originator's variables were mapped to BODC parameter codes.

Processing by originator of moored acoustic doppler current profiler (ADCP) from cruise DY120 using Teledyne RDI Sentinel Workhorse 600kHz

Data Acquisition

CLASS Darwin Mounds mooring was deployed from cruise DY120 on 23rd October 2020 and was recovered by cruise JC238 on 27th July 2022.

A downwards-looking 600 kHz ADCP was deployed on a single-point mooring at 31 m above the seabed to measure currents. Measurements presented include velocity (east, north, vertical, error, magnitude, direction), echo amplitudes (for ehac of the four beams and an average value), and ancillary data (pitch, roll, heading, temperature, depth based on pressure), and orientation.

Data were processed from raw .000 files in WinADCP, outputting only data that inlcudes water column measurements.

Calibration

Deployment Cruise

Further information can be found in the DY120 Cruise report.

Recovery Cruise

Further information can be found in the JC238 Cruise report.

Project Information

Marine LTSS: CLASS (Climate Linked Atlantic Sector Science)

Introduction

CLASS is a five year (2018 to 2023) programme, funded by the Natural Environment Research Council (NERC) and extended until March 2024.

Scientific Rationale

The ocean plays a vital role in sustaining life on planet Earth, providing us with both living resources and climate regulation. The trajectory of anthropogenically driven climate change will be substantially controlled by the ocean due to its absorption of excess heat and carbon from the atmosphere, with consequent impacts on ocean resources that remain poorly understood. In an era of rapid planetary change, expanding global population and intense resource exploitation, it is vital that there are internationally coordinated ocean observing and prediction systems so policy makers can make sound evidence-based decisions about how to manage our interaction with the ocean. CLASS will underpin the UK contribution to these systems, documenting and understanding change in the marine environment, evaluating the impact of climate change and effectiveness of conservation measures and predicting the future evolution of marine environments. Over the five-year period CLASS will enhance the cost-effectiveness of observing systems by migrating them towards cutting edge autonomous technologies and developing new sensors. Finally, CLASS will create effective engagement activities ensuring academic partners have transparent access to NERC marine science capability through graduate training partnerships and access to shipborne, lab based and autonomous facilities, and modelling capabilities.

Data Activity or Cruise Information

Data Activity

Darwin Mounds Long-Term Mooring - October 2020

This rig was deployed as a contribution to the Climate Linked Atlantic Section Science (CLASS) project's sustained observations and marine protected area studies, supported by the UK Natural Environment Research Council. 'DMLTM_102020' refers to the deployment of the Darwin Sea Mounds (DMLTM) mooring in October 2020 ('102020'), located North-west of Cape Wrath, Scotland. Further details of the deployment can be found in the DY120 cruise report.

Data summary

Instrumentation

The Darwin Mounds long-term mooring, deployed on DY120, was anchored by a 1000 kg chain clump anchor and kept buoyant with 3 glass spheres. This mooring was subsurface.

Related Data Activity activities are detailed in Appendix 1

Cruise

Complete Cruise Metadata Report is available here

Fixed Station Information

Fixed Station Information

Fixed Station - Darwin Mounds Marine Protected Area (MPA) Special Area of Conservation (SAC)

The Darwin Mounds are located approximately 160 km north-west of Cape Wrath, Scotland, at the north end of the Rockall Trough. The site was designated a Marine Protected Area (MPA) in June 2002 and was formally assigned a Special Area of Conservation (SAC) from March 2018. The site area is approximately 1377 km² and the water depth ranges from 710 - 1129 m. The site consists of a large number of coral-topped 'sand volcanoes' composed of sand overlying mud. The individual mounds are up to 75 m wide and 5 m high and are morphologically unique in UK waters. The mounds themselves are unusual geological features that are thought to have been formed by fluid expulsion from the seabed. The mounds are most elevated to the north of the site and diminish in height to the south. There are two denser regions of mounds in the north-east and north-west of the site. The north-east field of the Darwin Mounds measures approximately 13 km by 9 km and contains approximately 150 mounds, whereas the north-west field measures approximately 13 km by 4 km and contains approximately 75 mounds.

The mounds in the northern part of the site show an acoustic signature of a 'tail' which generally lies to the south-west of the mound feature consisting of elongate to oval patches up to 500 m long. The 'tail' feature of the mounds is thought to be unique globally. The tails are not topographically distinct from the surrounding seabed but are covered with a fine veneer of sand. They support substantial numbers of the xenophyophore Syringammina fragilissima (a single-celled organism that can grow up to 20 cm in diameter), in densities greater than the surrounding seabed.

On the majority of the mounds there are also multiple colonies of Lophelia pertusa growing, which in many cases have formed thickets which arise from the surface of the mound. This site was the first observed record of cold-water coral reefs growing on sand at the time of discovery. Like the topography of the mounds, the frequency of coral communities diminishes towards the south of the mound field. Although the reef habitat on top of the mounds is formed primarily from Lophelia pertusa, another cold-water coral Madrepora oculata is also present. The thickets of cold-water corals provide a habitat for echiuran worms, brittlestars, brisingiid starfish and sponges. Various fish have been observed among the mounds, but not at higher densities than the wider environment.

For further information see the JNCC website. Image available to download here.

Sampling History

Related Fixed Station activities are detailed in Appendix 2

BODC Quality Control Flags

The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:

SeaDataNet Quality Control Flags

The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:

Appendix 1: DMLTM_102020

Related series for this Data Activity 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.

Appendix 2: Darwin Mounds Marine Protected Area, Special Area of Conservation

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.