Metadata Report for BODC Series Reference Number 2223807

• 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

BAS Long Term Monitoring and Survey RRS James Clark Ross JR15004 navigation quality control report

Null HEADCM01 data were found from 19 February 2016 07:44:00 hours to the end of the cruise period.

MBANZZ01 was extensively flagged due to anomalous data (e.g. reflection, noise or jumps in data). Data should be used with caution.

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

BAS Long Term Monitoring and Survey RRS James Clark Ross JR15004 Underway Cruise Document

Cruise details

JR15004 consisted of a series of science modules operating at different spatial scales in the South Orkney Island region of the Scotia Sea. The main objectives for the cruise were:

• to characterise physical and biological environment on a latitudinal transect upstream of the South Orkney region
• to characterise the physical and biological environment of the northern shelf and shelf break region of the South Orkney Islands.
• to determine the fine scale distribution of krill across the most heavily fished area of the north coast of the South Orkney Islands
• to understand physical-biological drivers at the small scale of the Western Canyon
• to map distribution and biomass of krill and predators in large krill aggregation detected on shelf break of Coronation Island
• to understand physical-biological drivers of behaviour in krill aggregations
• to calibrate EK60 and EK80 systems on JCR. WBAT stand-alone system for moorings and CTD. RDI ship-mounted ADCP

The research activities link with concurrent observations from commercial fishing vessels operating in the region, together with a regional 5 day krill survey undertaken by Norwegian fishing vessel FV Saga Sea. The ship-based activities are also tightly linked to predator tracking studies being undertaken from key penguin and fur seal colonies in the South Orkney region.

Upon leaving port, the ship sailed towards Scotia Bay, then the northern shelf of Coronation Island, the Inaccessible Canyon, Signy and from there transited back to Mare Harbour, Falklands.

Data were not processed by the originator.

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

BAS Long Term Monitoring and Survey RRS James Clark Ross JR15004 Underway Navigation Instrumentation

The following scientific navigational and bathymetry systems were fitted.

Furuno GPS/WAAS Navigator GP32

The GP32 is an advanced GPS navigator with a Wide Area Augmentation System (WAAS) receiver which can receive up to 12 discrete GPS channels, all-in-view, and also has DGPS capabilities.

The WAAS applies correction data by means of geostationary satellites. The reference stations on earth monitor the GPS constellation and route GPS error data to the WAAS satellite via the master earth station.

This equipment is comprised of a compact unit designed for coastal activities with several display modes, e.g. Plotter, Nav Data, Steering, Highway, Speedometer and two other costumisable modes. The data can be viewed in WGS-84 or other geodetic systems.

Specifications

The equipment's specification sheet can be accessed Furuno GP32

Kongsberg Seatex Seapath 200 GPS and Gyrocompass

The Seapath 200 is a highly accurate, real-time heading, attitude and position information system that integrates the best signal characteristics of Inertial Measurement Units (IMU) and Global Positioning System (GPS), using a differential GPS method to acquire this data.

The high-rate motion data is obtained from the Seatex MRU5 inertial sensor and two fixed baseline GPS carrier-phase receivers. The raw data is integrated in a Kalman filter in the Seapath Processing Unit. The IMU contains an accurate linear accelerometer and Bosch Coriolis force angular rate gyros (CFG).

This system is equipped to utilise up to six different DGPS reference stations, it checks for consistency within measurements from the different sensors to ensure reliability and rejects noisy data or reports its inaccuracy. The data is available through various output protocols, RS-232, RS-422 and Ethernet.

This instrument is no longer in production; the main characteristics are presented below, and the specification sheet can be accessed here Kongsberg Seatex Seapath 200 .

Specifications

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.

BAS Long Term Monitoring and Survey RRS James Clark Ross JR15004 Underway Navigation Document

Content of data series

Data Processing Procedures

Originator's Data Processing

No processing was done on the data streams by the originator. The files used contain the raw data as collected by the ship's logging system.

Files delivered to BODC

BODC Data Processing

The files mentioned above were selected for data banking as they contain the best version of position, heading and bathymetry. Data were banked at BODC following standard data banking procedures, including reduction through averaging, checking navigation channels for improbable values, working out speed over ground, and screening the data for anomalous values.

The originator's variables were mapped to appropriate BODC parameter codes as follows:

furuno-gga

gyro

ea600

em122

BODC's procedures included the transfer of originator's parameters into BODC codes and visual screening in Edserplo. N flags were applied to absent values during the data transfer.

Position

One gap was identified in ALATGP01 and ALONGP01 from 19 January 2016 16:44:00 hours to 19 January 2016 16:54:00 hours. These cycles were interpolated using established procedures.

Ship's velocities

Ship's eastward and northward velocities were calculated from the main latitude and longitude channels. No flags were needed as data are of good quality.

Distance Run

Distance run was calculated from the main latitude and longitude channels, starting from the beginning of the cruise period.

Ship's orientation

Data were loaded and screening and it was found that from 19 February 2016 07:44:00 hours data were all null. Flags were applied accordingly.

Bathymetry

Bathymetry data from the multibeam and echosounder were loaded and screened. It was found that multibeam data were much less than the echsounder data. M flags were extensively applied to MBANZZ01 to all cycles where data were considered anomalous due to reflection or jumps.

Project Information

BAS Long Term Monitoring and Survey

Introduction

The Long Term Monitoring and Survey project (LTMS) has been running since the British Antarctic Survey (BAS) was created. This project is one of the BAS core projects, with several groups of scientists collecting various types of data e.g biological, geological, atmospheric, among others.

Data collection is achievable through a wide scope of instruments and platforms, e.g. the Antarctic research stations, autonomous instrument platforms deployed on or from BAS research ships, BAS aircrafts, satellite remote sensing and others.

Scientific Objectives

This project was implemented in order to measure change and variability in the Earth system. Its long term duration allows for the monitoring of processes that could be missed in shorter term studies and experiments. The data collected is also used to check and improve the reliability of models used to stimulate and predict the behavior of the Earth system.

The main objectives are:

• Topographic survey
• Geosciences survey
• Biological survey and monitoring
• Atmospheric and oceanographic monitoring

Data Availability

The data sets obtained through this project are available to the academic community.

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: