Metadata Report for BODC Series Reference Number 1080180

• 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 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

D321B MSS Microstructure Profiler: Processing undertaken by BODC

96 individual ASCII .TOB files were supplied to BODC by scientists at SAMS. These were accompanied by 96 associated raw (.MRD) data files, as output directly from the profiler.

The .TOB files, representing the definitive version of MSS data (as required for the scientific aims of cruise D321B) were reformatted to BODC's internal QXF (netCDF) format. Latitude, longitude and bathymetry (where available) at the start of each profile were extracted from the ship's underway data stream and merged with the MSS data (using profile start time as the linking mechanism).

As part of the reformatting exercise, variables were also mapped to standard BODC parameter codes as described in the table below:

The reformatted data were visualised using the in-house EDSERPLO software. Suspect data were marked with an appropriate quality control flag, whilst missing data were highlighted by assigning an appropriate absent data value and applying a quality control flag.

Note: The raw .MRD files for this cruise are preserved in the BODC archive and can be supplied upon request.

RRS Discovery Cruise D321B Microstructure Profiler: Originator Processing

Sampling Strategy

A total of five microstructure profiling surveys took place during the cruise, each at a distinct locality within the Wyville Thomson basin. In total, 104 individual profiling events were completed between 03/09/2007 and 06/09/2007, all of which were performed with a single MSS090 profiler. The following table summarises the sampling campaign:

NB MSS001-MSS005 and MSS052 were testing events and therefore not included in the total deployment count.

The microstructure profiler was deployed from a winch mounted on the gunnel of the starboard quarter of the ship. 1000 metres of neutrally buoyant Kevlar cored conducting cable was used on the winch to allow profiling to a maximum depth of 801 metres. Ultimately, the maximum depth achieved on each profile was dependent on weather conditions and the ship's speed through the water (typically in the region of 0.5 knots, but occasionally as great as 1 knot). As a result, a maximum depth of 630 metres was more typically achieved.

Data Processing

Each profile generated a single raw .MRD file. These were post-processed after the cruise following SAMS standard procedures for MSS data, which utilise the ISW processing software (MSSpro). A summary of the main SAMS processing steps is presented below (as outlined in the report for cruise D340B). More comprehensive details are available in the MSSpro software manual.

SAMS processing steps:

• Conversion of sensor output voltages to shear measurements using the gradient of velocity as a function of pressure through the water column

• Application of calibration coefficients specific to the shear probes

• Checking of shear spectra with Nasmyth's universal spectrum of turbulence in the ocean and subsequent application of a low pass filter to remove high frequency noise from the profiles

• Calculation of the dissipation rate of turbulent kinteic energy (epsilon) over the measurable range from the profiler. Spectral fitting using the Nasmyth spectrum to address those frequencies outside of the range

• Generation of 1 metre-binned ASCII (.tob) files containing the key variables identified by the originator.

Post processing resulted in the creation of 96 individual .tob files from the original 104 profiling events. An aborted deployment (MSS056) is noted in the cruise report. Reasons for the absence of data from the remaining profiles (MSS014, MSS021, MSS035, MSS039, MSS052, MSS081 and MSS105) are not documented, but it is thought that there were data quality issues uncovered at the time of post-cruise processing.

References

Inall M. E., 2009. RRS Discovery Cruise D340b. Dunstaffnage to Govan via Barra Head and the Surrounding Shelf. Internal Report No 265. Scottish Association for Marine Science.

Sherwin T. A. et al., 2007. RRS Discovery Cruise D321b. Reykjavic to Clyde via Rockall, Scotland and the Wyville Thomson Ridge. Internal Report No 255. Scottish Association for Marine Science.

D321B Microstructure Profiler Instrumentation

The microstructure profiler deployed during the cruise was a MSS90 profiler (Serial Number 034), which had undergone modification to enable operation in up to 4000 m water depth. Measurements are made at 380 Hz.

The MSS90 sensor configuration is detailed in the following table:

Sea and Sun Technology MSS 90 Microstructure Profiler

A multiparameter probe used to measure micro-scale water stratification as well as the intensity of small scale turbulence in the water column in marine and limnic environments. The instrument can be used for free sinking or rising measurements. The instruments sinking or rising velocity can be adjusted by a combination of weights and buoyancy elements. It has a depth rating of approximately 500 m, samples at 1024 Hz and is equipped with high resolution micro-structure and turbulence sensors (temperature, current shear) and standard CTD sensors (temperature, conductivity, pressure). All microstructure channels have a response time of less than 12 ms. The unit includes internal sensors to control for vibrations and tilt internally.

The system comprises the profiler, a winch, a probe interface and data acquisition computer. Additional sensors, such as oxygen and optical scattering, can be attached to the profiler. The instrument can support up to a maximum of nine sensors.

There are two different models available which have the same electronic and sensor equipment, with the difference relating to the size and weight of the instruments, see the table below for further details. The shear sensor data quality of the MSS90L is however superior due to the higher mass and stability.

Further details can be found in the manufacturer's manual.

Project Information

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 - 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:

• National Oceanography Centre, Southampton (NOCS)
• Plymouth Marine Laboratory (PML)
• Marine Biological Association (MBA)
• Sir Alister Hardy Foundation for Marine Science (SAHFOS)
• Proudman Oceanographic Laboratory (POL)
• Scottish Association for Marine Science (SAMS)
• Sea Mammal Research Unit (SMRU)

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:

• British Oceanographic Data Centre (BODC), hosted at POL
• Permanent Service for Mean Sea Level (PSMSL), hosted at POL
• Culture Collection of Algae and Protozoa (CCAP), hosted at SAMS

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:

• improve knowledge of how the seas behave, not just now but in the future;
• help assess what that might mean for the Earth system and for society;
• assist in developing sustainable solutions for the management of marine resources for future generations;
• enhance the research capabilities and facilities available for UK marine science.

In order to address these aims there are nine science themes supported by the Oceans 2025 programme:

• Climate, circulation and sea level (Theme 1)
• Marine biogeochemical cycles (Theme 2)
• Shelf and coastal processes (Theme 3)
• Biodiversity and ecosystem functioning (Theme 4)
• Continental margins and deep ocean (Theme 5)
• Sustainable marine resources (Theme 6)
• Technology development (Theme 8)
• Next generation ocean prediction (Theme 9)
• Integration of sustained observations in the marine environment (Theme 10)

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:

• physical, biological and chemical parameters sampling throughout the North and South Atlantic during collaborative research cruises aboard NERC's research vessels RRS Discovery, RRS James Cook and RRS James Clark Ross;
• the Continuous Plankton Recorder being deployed by SAHFOS in the North Atlantic and North Pacific on 'ships of opportunity';
• physical parameters measured and relayed in near real-time by fixed moorings and ARGO floats;
• coastal and shelf sea observatory data (Liverpool Bay Coastal Observatory (LBCO) and Western Channel Observatory (WCO)) using the RV Prince Madog and RV Quest.

The data is to be fed into models for validation and future projections. Greater detail can be found in the Theme documents.

Data Activity or Cruise Information

Cruise

Complete Cruise Metadata Report is available here

Fixed Station Information

No Fixed Station Information held for the Series

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: