Metadata Report for BODC Series Reference Number 2207555

• 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

RRS James Clarke Ross JR17007 Navigation Quality Control Report

Position

Position channels look good. Two gaps just at the start and end of the dataset, which were trimmed off at the end of processing. Flags were automatically applied to this.

Heading

Heading channel looks good. There are some large fluctuations within the permitted maximum and minimum parameter values and there are some parts of the datasets where absent values have been recorded. These absent values were automatically flagged.

Bathymetry

All bathymetry channels show a similar pattern. Both the singlebeam and the multibeam follow GEBCO’s trend quite well. The quality of the multi-beam dataset is moderate containing a small amount of noise but has long periods with only absent value readings. Flags were automatically assigned to the absent values and to the unrealistic noisy values.

The Single Beam channel looks very good overall with only approximately 15-20% of the data flagged. It contains some noisy patches and some dropouts but still compares well with GEBCO. The noisy patches and drop outs were flagged accordingly.

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

RRS James Clark Ross Cruise JR17007 Underway Document

Cruise details

Kongsberg EA600 Single Beam Echosounder

The EA600 is a single beam echosounder with full ocean depth capability designed for bathymetric surveys. It measures water depth by monitoring the travel time of an acoustic signal that is transmitted from the ship, reflected off the seabed and received back at the ship.

The main components of the system are hull-mounted transducers linked to general purpose transceivers (GPTs). Up to four GPTs, each controlling one or more transducers, may be operated simultaneously. The GPT generates a signal, which is transmitted into the water column as an acoustic pulse by the transducer array, and the returning echo is recorded by the GPT. GPTs are in turn linked to a combined display and processor, where adjustments (such as sound-speed corrections) may be applied to the data. Available frequencies span from 12 to 710 kHz, and each GPT may operate at a separate frequency. A variety of transducers is available for water depths up to 11,000 m.

The EA600 stores all data internally but has a USB port which allows the possibility of connecting a CD-ROM/DVD drive to read and write the data. All echo data can be stored as files: bitmap, sample, depth or sidescan data.

In deeper waters, the EA600 supports a multipulse function, allowing for a higher pinger rate. While on passive mode, the pinger is normally attached to a device, with the purpose of tracking and displaying its current depth.

The EA600 replaced the EA500 in 2000.

Specifications

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

Kongsberg EM122 12kHz Multibeam Echosounder

The EM122 is designed to perform seabed mapping to full ocean depth with a high resolution, coverage and accuracy. Beam focusing is applied both during reception and transmission. The system has up to 288 beams/432 soundings per swath with pointing angles, which are automatically adjusted according to achievable coverage or operator defined limits.

This model uses both Continuous Wave and Frequency Modulated sweep pulses with pulse compression on reception, in order to increase the maximum useful swath width. The transmit fan is split in several individual sectors, with independent active steering, in order to compensate for the vessel movements.

In multiplying mode, two swaths per ping cycle are generated, with up to 864 soundings. The beam spacing is equidistant or equiangular and the transmit fan is duplicated and transmitted with a small difference in along track tilt, which takes into account depth coverage and vessel speed, to give a constant sounding separation along track. In high density mode, more than one sounding per beam can be produced, such that horizontal resolution is increased and is almost constant over the whole swath.

The EM122 transducers are modular linear arrays in a Mills cross configuration with separate units for transmit and receive. If used to deliver sub-bottom profiling capabilities with a very narrow beamwidth, this system is known as SBP120 Sub-Bottom Profiler.

The specification sheet can be accessed here Kongsberg EM122.

Specifications

EM122 versions

Kongsberg Seatex Seapath 320+ Precise Heading, Attitude and Positioning Sensor

The Seapath 320+ is a navigational system that combines two Global Navigation Satellite System (GNSS) receivers with a MRU 5+ inertial sensor to provide high resolution and accuracy positional data. The inertial sensor employs linear accelerometers and unique microelectromechanical systems (MEMS)-type angular rate gyros to provide 0.01 RMS pitch and roll accuracy. The GNSS receivers can use multiple satellite constellations (GPS, GLONASS and Galileo, when available), and combine data from these to improve heading and positional measurements. In case of missing data from one GNSS receiver, the other receiver provides position and velocity, and the inertial sensor provides heading from its internal rate sensors.

The main characteristics are presented below, and the specification sheet can be accessed here Kongsberg Seatex Seapath 320+ .

Specifications

RRS James Clark Ross cruise JR17007 navigation instrumentation

The following scientific navigational and bathymetric systems were fitted.

Sperry Marine MK-37 Gyrocompass

A family of instruments that contain a controlled gyroscope which seeks and aligns itself with the meridian and points to true north. They use the properties of the gyroscope in combination with the rotation of the earth and the effect of gravity. The effects of varying speed and latitude are compensated for by the use of manually operated controls. Models MOD I, MOD O, MOD D, MOD D/E are all with an analog output Step or/and Syncro. MOD VT is the latest model with NMEA Data output as well.

Further specifications for MOD VT can be found in the manufacturer's specification document.

Further information for MOD D/E can be found in the user manual.

RRS James Clark Ross Cruise JR17007 Navigation and Bathymetry Processing Procedures Document

Originator's Data Processing

The navigation and bathymetric data were measured by several different instruments and the data were logged every second to the SCS system and stored in comma separated ACO format. Each instrument logged data to one individual file and the associated header information is stored in TPL files.

The originator's data files exhibited the same common format for the first four columns: Year (yyyy), Julian day.day fraction (days), Julian day (days), day fraction (days). The remaining columns contain the actual data values.

The table below shows the original files delivered to BODC that contained the data in the final data series, along with start and end dates and times of each file.

BODC Data Processing

The data were reformatted to BODC internal format using standard banking procedures. Data were averaged at 60 second intervals. The following table shows how variables within the file were mapped to appropriate BODC parameter codes:

All the reformatted data were visualised using the in-house EDSERPLO software. Suspect data were marked by adding an appropriate quality control flag.

Position

A check was run on positional data to identify gaps and improbable values (through the calculation of speed). There was one gap in the positional data at the start and end of the file, produced during loading to the BODC system. These gaps were trimmed after processing was complete.

Ship velocities

Ship velocities were calculated from the main latitude and longitude channels using standard BODC procedures.

Distance Run

Distance run was calculated from the main latitude and longitude channels, starting from the beginning of the file, using BODC standard procedures.

GEBCO

GEBCO bathymetry was added to the file using the main latitude and longitude channels.

Bathymetry

Bathymetry data were screened independently as well as against GEBCO bathymetry measurements. The single-beam echo sounder was deemed to be the best quality source of bathymetry and was retained in the file.

Calibration

No sample calibrations were applied to these data.

Project Information

Changing Arctic Ocean: Implications for marine biology and biogeochemistry

Changing Arctic Ocean (CAO) is a £16 million, five year (2017-2022) research programme initially funded by the Natural Environment Research Council (NERC). The aim of the CAO programme is to understand how change in the physical environment (ice and ocean) will affect the large-scale ecosystem structure and biogeochemical functioning of the Arctic Ocean, the potential major impacts and provide projections for future ecosystem services. In July 2018, additional projects were added to the programme that were jointly funded by NERC and the German Federal Ministry of Education and Research.

Background

The Arctic Ocean is responding to global climate change in ways that are not yet fully understood and in some cases, not yet identified. The impacts of change in the Arctic are global in range and international in importance. To achieve the aim, the programme has two key research challenges:

• To develop quantified understanding of the structure and functioning of Arctic ecosystems.
• To understand the sensitivity of Arctic ecosystem structure, functioning and services to multiple stressors and the development of projections of the impacts of change.

The decision to fund the CAO project was both scientific and political and is the second largest research programme funded by NERC.

The programme involves 33 organisations, the majority of which are research institutions in the UK and Germany, and over 170 scientists. The programme consists of four large projects with an additional 12 research projects added in July 2018.

Further information can be found on the Changing Arctic Ocean website.

Participants

There are 33 organisations involved in the Changing Arctic Ocean project, these are:

• Alfred Wegener Institut (AWI)
• Bangor University
• British Antarctic Survey (BAS)
• Centre for Environment, Fisheries and Aquaculture Science (CEFAS)
• Durham University
• GEOMAR
• Helmholtz-Zentrum Geesthacht Centre for Materials and Coastal Research
• Lancaster University
• Marine Biological Association (MBA)
• Max Planck Institute for the Science of Human History
• National Oceanography Centre (NOC)
• Newcastle University
• Northumbria University
• Ocean Atmosphere Systems GmbH
• Plymouth Marine Laboratory (PML)
• Scottish Association for Marine Science (SAMS)
• Scottish Universities Environmental Research Centre (SUERC)
• Université Libre de Bruxelles
• University College London (UCL)
• University of Bristol
• University of East Anglia (UEA)
• University of Edinburgh
• University of Glasgow
• University of Huddersfield
• University of Leeds
• University of Liverpool
• University of Manchester
• University of Oldenburg
• University of Oxford
• University of Southampton
• University of St Andrews
• University of Stirling
• University of Strathclyde

In addition to the core organisation, there are a number of international collaborators.

Research Details

The four large projects funded by NERC are:

• Arctic Productivity in the seasonal Ice Zone (Arctic PRIZE)
• Can we detect changes in Arctic ecosystems? (ARISE)
• The Changing Arctic Ocean Seafloor (ChAOS) - How changing sea ice conditions impact biological communities, biogeochemical processes and ecosystems
• Mechanistic understanding of the role of diatoms in the success of the Arctic Calanus complex and implications for a warmer Arctic (DIAPOD)

The additional 12 projects added in July 2018 funded jointly by NERC and the German Federal Ministry of Education and Research are:

• Advective Pathways of nutrients and key Ecological substances in the Arctic (APEAR)
• How will changing freshwater export and terrestrial permafrost thaw influence the Arctic Ocean? (CACOON)
• Chronobiology of changing Arctic Sea Ecosystems (CHASE)
• Potential benefits and risks of borealisation for fish stocks and ecosystems in a changing Arctic Ocean (Coldfish)
• Diatom Autecological Responses with Changes To Ice Cover (Diatom-ARCTIC)
• Ecosystem functions controlled by sea ice and light in a changing Arctic (Eco-Light)
• Effects of ice stressors and pollutants on the Arctic marine cryosphere (EISPAC)
• Linking Oceanography and Multi-specific, spatially-Variable Interactions of seabirds and their prey in the Arctic (LOMVIA)
• Understanding the links between pelagic microbial ecosystems and organic matter cycling in the changing Arctic (Micro-ARC)
• Microbes to Megafauna Modelling of Arctic Seas (MiMeMo)
• Primary productivity driven by escalating Arctic nutrient fluxes? (PEANUTS)
• Pathways and emissions of climate-relevant trace gases in a changing Arctic Ocean (PETRA)

Fieldwork and Data Collection

The programme consists of seven core cruises that survey areas in the Barents Sea and the Fram Strait on board the NERC research vessel RRS James Clark Ross. Measurements will include temperature, salinity, dissolved oxygen, dissolved inorganic carbon, total alkalinity, inorganic nutrients, oxygen and carbon isotopes and underway meteorological and surface ocean observations. In addition to ship based cruise datasets gliders, moorings and animal tags are part of the fieldwork. Further data are collected from model runs.

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: