Metadata Report for BODC Series Reference Number 1847019

• 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

All values for BB117R01 and CPHLPM02 were flagged suspect and no useable data were recovered from the sensors. These channels have been removed from the final file, however the original data can be made available on request.

RRS James Clark Ross JR15005 CTD Data Quality Report

The data were screened and any obvious outliers and spikes were looked at in closer detail and flagged if necessary.

AHSFZZ01 channel has been flagged where values are constant or increase with depth. The altimeter only collects good data within 100 m of the seabed and these instances of constant values or increases with depth occur more than 100 m from the seabed.

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

Sea-Bird Dissolved Oxygen Sensor SBE 43 and SBE 43F

The SBE 43 is a dissolved oxygen sensor designed for marine applications. It incorporates a high-performance Clark polarographic membrane with a pump that continuously plumbs water through it, preventing algal growth and the development of anoxic conditions when the sensor is taking measurements.

Two configurations are available: SBE 43 produces a voltage output and can be incorporated with any Sea-Bird CTD that accepts input from a 0-5 volt auxiliary sensor, while the SBE 43F produces a frequency output and can be integrated with an SBE 52-MP (Moored Profiler CTD) or used for OEM applications. The specifications below are common to both.

Specifications

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

RRS James Clark Ross JR15005 CTD Instrumentation

A Sea-Bird 911 plus CTD system was used on cruise JR15005. This was mounted on a SBE-32 carousel water sampler holding 24 12-litre Niskin bottles. The CTD was fitted with the following scientific sensors:

External calibration dates are unavailable.

Sea-Bird Electronics SBE 911 and SBE 917 series CTD profilers

The SBE 911 and SBE 917 series of conductivity-temperature-depth (CTD) units are used to collect hydrographic profiles, including temperature, conductivity and pressure as standard. Each profiler consists of an underwater unit and deck unit or SEARAM. Auxiliary sensors, such as fluorometers, dissolved oxygen sensors and transmissometers, and carousel water samplers are commonly added to the underwater unit.

Underwater unit

The CTD underwater unit (SBE 9 or SBE 9 plus) comprises a protective cage (usually with a carousel water sampler), including a main pressure housing containing power supplies, acquisition electronics, telemetry circuitry, and a suite of modular sensors. The original SBE 9 incorporated Sea-Bird's standard modular SBE 3 temperature sensor and SBE 4 conductivity sensor, and a Paroscientific Digiquartz pressure sensor. The conductivity cell was connected to a pump-fed plastic tubing circuit that could include auxiliary sensors. Each SBE 9 unit was custom built to individual specification. The SBE 9 was replaced in 1997 by an off-the-shelf version, termed the SBE 9 plus, that incorporated the SBE 3 plus (or SBE 3P) temperature sensor, SBE 4C conductivity sensor and a Paroscientific Digiquartz pressure sensor. Sensors could be connected to a pump-fed plastic tubing circuit or stand-alone.

Temperature, conductivity and pressure sensors

The conductivity, temperature, and pressure sensors supplied with Sea-Bird CTD systems have outputs in the form of variable frequencies, which are measured using high-speed parallel counters. The resulting count totals are converted to numeric representations of the original frequencies, which bear a direct relationship to temperature, conductivity or pressure. Sampling frequencies for these sensors are typically set at 24 Hz.

The temperature sensing element is a glass-coated thermistor bead, pressure-protected inside a stainless steel tube, while the conductivity sensing element is a cylindrical, flow-through, borosilicate glass cell with three internal platinum electrodes. Thermistor resistance or conductivity cell resistance, respectively, is the controlling element in an optimized Wien Bridge oscillator circuit, which produces a frequency output that can be converted to a temperature or conductivity reading. These sensors are available with depth ratings of 6800 m (aluminium housing) or 10500 m (titanium housing). The Paroscientific Digiquartz pressure sensor comprises a quartz crystal resonator that responds to pressure-induced stress, and temperature is measured for thermal compensation of the calculated pressure.

Additional sensors

Optional sensors for dissolved oxygen, pH, light transmission, fluorescence and others do not require the very high levels of resolution needed in the primary CTD channels, nor do these sensors generally offer variable frequency outputs. Accordingly, signals from the auxiliary sensors are acquired using a conventional voltage-input multiplexed A/D converter (optional). Some Sea-Bird CTDs use a strain gauge pressure sensor (Senso-Metrics) in which case their pressure output data is in the same form as that from the auxiliary sensors as described above.

Deck unit or SEARAM

Each underwater unit is connected to a power supply and data logging system: the SBE 11 (or SBE 11 plus) deck unit allows real-time interfacing between the deck and the underwater unit via a conductive wire, while the submersible SBE 17 (or SBE 17 plus) SEARAM plugs directly into the underwater unit and data are downloaded on recovery of the CTD. The combination of SBE 9 and SBE 17 or SBE 11 are termed SBE 917 or SBE 911, respectively, while the combinations of SBE 9 plus and SBE 17 plus or SBE 11 plus are termed SBE 917 plus or SBE 911 plus.

Specifications

Specifications for the SBE 9 plus underwater unit are listed below:

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

Chelsea Technologies Group Aquatracka MKIII fluorometer

The Chelsea Technologies Group Aquatracka MKIII is a logarithmic response fluorometer. Filters are available to enable the instrument to measure chlorophyll, rhodamine, fluorescein and turbidity.

It uses a pulsed (5.5 Hz) xenon light source discharging along two signal paths to eliminate variations in the flashlamp intensity. The reference path measures the intensity of the light source whilst the signal path measures the intensity of the light emitted from the specimen under test. The reference signal and the emitted light signals are then applied to a ratiometric circuit. In this circuit, the ratio of returned signal to reference signal is computed and scaled logarithmically to achieve a wide dynamic range. The logarithmic conversion accuracy is maintained at better than one percent of the reading over the full output range of the instrument.

Two variants of the instrument are available, both manufactured in titanium, capable of operating in depths from shallow water down to 2000 m and 6000 m respectively. The optical characteristics of the instrument in its different detection modes are visible below:

* The wavelengths for the turbidity filters are customer selectable but must be in the range 400 to 700 nm. The same wavelength is used in the excitation path and the emission path.

The instrument measures chlorophyll a, rhodamine and fluorescein with a concentration range of 0.01 µg l^-1 to 100 µg l^-1. The concentration range for turbidity is 0.01 to 100 FTU (other wavelengths are available on request).

The instrument accuracy is ± 0.02 µg l^-1 (or ± 3% of the reading, whichever is greater) for chlorophyll a, rhodamine and fluorescein. The accuracy for turbidity, over a 0 - 10 FTU range, is ± 0.02 FTU (or ± 3% of the reading, whichever is greater).

Further details are available from the Aquatracka MKIII specification sheet.

WETLabs ECO-FL Fluorometer

The Environmental Characterization Optics series of single channel fluorometers are designed to measure concentrations of natural and synthetic substances in water, and are therefore useful for biological monitoring and dye trace studies. Selected excitation and emission filters allow detection of the following substances: chlorophyll-a, coloured dissolved organic matter (CDOM), uranine (fluorescein), rhodamine, phycoerythrin and phycocyanin.

The ECO-FL can operate continuously or periodically and has two different types of connectors to output the data (analogue and RS-232 serial output). The potted optics block results in long term stability of the instrument and the optional anti-biofouling technology delivers truly long term field measurements.

In addition to the standard model, five variants are available, and the differences between these and the basic ECO-FL are listed below:

• FL(RT): similar to the FL but operates continuously when power is supplied
• FL(RT)D: similar model to the (RT) but has a depth rating of 6000 m
• FLB: includes internal batteries for autonomous operation and periodic sampling
• FLS: similar to FLB but has an integrated anti-fouling bio-wiper
• FLSB: similar to the FLS, but includes internal batteries for autonomous operation

Specifications

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

Biospherical Instruments Log Quantum Cosine Irradiance Sensor QCD-905L

The QCD-905L is a submersible radiometer designed to measure irradiance over Photosynthetically Active Radiation (PAR) wavelengths (400-700 nm). It features a cosine directional response when fully immersed in water.

The sensor is a blue-enhanced high stability silicon photovoltaic detector with dielectric and absorbing glass filter assembly, and produces a logarithmic output. Normal output range is -1 to 6 volts with 1 volt per decade. Typically, the instrument outputs 5 volts for full sunlight and has a minimum output of 0.001% full sunlight, where typical noon solar irradiance is 1.5 to 2 x 10¹⁷ quanta cm^-2 s^-1. The instrument can be calibrated with constants for µE cm^-2 s^-1 or quanta cm^-2 s^-1.

The QCD-905L can be coupled to a fixed range data acquisition system like a CTD (Conductivity-Temperature-Depth) profiler or current meter. It has an aluminium and PET housing, and a depth rating of 7000 m.

Specifications

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

WETLabs Single-angle Backscattering Meter ECO BB

An optical scattering sensor that measures scattering at 117°. This angle was determined as a minimum convergence point for variations in the volume scattering function induced by suspended materials and water. The measured signal is less determined by the type and size of the materials in the water and is more directly correlated to their concentration.

Several versions are available, with minor differences in their specifications:

• ECO BB(RT)provides analog or RS-232 serial output with 4000 count range
• ECO BB(RT)D adds the possibility of being deployed in depths up to 6000 m while keeping the capabilities of ECO BB(RT)
• ECO BB provides the capabilities of ECO BB(RT) with periodic sampling
• ECO BBB is similar to ECO BB but with internal batteries for autonomous operation
• ECO BBS is similar to ECO BB but with an integrated anti-fouling bio-wiper
• ECO BBSB has the capabilities of ECO BBS but with internal batteries for autonomous operation

Specifications

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

Tritech Digital Precision Altimeter PA200

This altimeter is a sonar ranging device that gives the height above the sea bed when mounted vertically. When mounted in any other attitude the sensor provides a subsea distance. It can be configured to operate on its own or under control from an external unit and can be supplied with simultaneous analogue and digital outputs, allowing them to interface to PC devices, data loggers, telemetry systems and multiplexers.

These instruments can be supplied with different housings, stainless steel, plastic and aluminum, which will limit the depth rating. There are three models available: the PA200-20S, PA200-10L and the PA500-6S, whose transducer options differ slightly.

Specifications

Common specifications are presented below

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

Paroscientific Absolute Pressure Transducers Series 3000 and 4000

Paroscientific Series 3000 and 4000 pressure transducers use a Digiquartz pressure sensor to provide high accuracy and precision data. The sensor comprises a quartz crystal resonator that responds to pressure-induced stress, and temperature is measured for thermal compensation of the calculated pressure.

The 3000 series of transducers includes one model, the 31K-101, whereas the 4000 series includes several models, listed in the table below. All transducers exhibit repeatability of better than ±0.01% full pressure scale, hysteresis of better than ±0.02% full scale and acceleration sensitivity of ±0.008% full scale /g (three axis average). Pressure resolution is better than 0.0001% and accuracy is typically 0.01% over a broad range of temperatures.

Differences between the models lie in their pressure and operating temperature ranges, as detailed below:

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

WETLabs C-Star transmissometer

This instrument is designed to measure beam transmittance by submersion or with an optional flow tube for pumped applications. It can be used in profiles, moorings or as part of an underway system.

Two models are available, a 25 cm pathlength, which can be built in aluminum or co-polymer, and a 10 cm pathlength with a plastic housing. Both have an analog output, but a digital model is also available.

This instrument has been updated to provide a high resolution RS232 data output, while maintaining the same design and characteristics.

Specifications

Further details are available in the manufacturer's specification sheet or user guide.

RRS James Clark Ross JR15005 CTD BODC Processing

Data were submitted to BODC in raw SeaBird format. The following procedures were applied using the SBE Data Processing software (Version 7.26.6.28):

• DATCNV - used to read in the raw CTD data file (.hex) which contained the data in engineering units and apply calibrations as appropriate through the instrument configurations (.con) file
• BOTSUM - generated summary data files (.btl file) for bottles fired at depth
• FILTER - filtered high frequency data from the pressure channel
• ALIGNCTD - aligned instruments to ensure no spikes in salinity, ran only for the oxygen channel and applied a 5 second correction
• CENTRAL THERMAL MASS - used alpha = 0.03 and 1/beta = 7 values to correct for conductivity errors induced by the transfer of heat from the conductivity cell to the seawater
• SECTION/LOOPEDIT - both procedures identified and removed the surface soak
• DERIVE - generated salinity and oxygen saturation data channels
• BINAVERAGE - averaged the files to 1 dbar in pressure channel
• STRIP - removed the primary and secondary salinity and oxygen concentration channels from the files

No further processing or calibrations were applied to these data. The final files in .cnv format were then transferred into BODC's internal NetCDf format and original variables were mapped to the appropiate BODC codes, as follows:

Potential Temperature (POTMCV01), Sigma-theta (SIGTPR01) and oxygen saturation (OXYSZZ01) have been re-derived and transferred to the internal NetCDF file.

Screening of data files were then completed using the in-house software EDSERPLO, which allows a visual inspection to take place of the data values and to flag any missing data or obvious spikes in the data.Please note the original data submitted to BODC can be made available on request.

RRS James Clark Ross JR15005 CTD Data Originator's Processing

Originator's Sampling

A total of 28 CTDs were deployed at various sites around the South Orkney Islands to aid investigations understanding diversity within and outside the South Orkney Islands Southern Shelf (SOISS) Marine Protected Area (MPA) region. CTDs were deployed for the purpose of gathering physical oceanographic data as well as for use in calibrating EM122 multibeam echosounder.

Project Information

South Orkney State of the Antarctic Ecosystem (SO-AntEco)

South Orkney State of the Antarctic Ecosystem (SO-AntEco) project was a British Antarctic Survey (BAS) yearlong funded programme from 20 August 2015 and 24 August 2016 and involved international collaboration with scientists from the British Antarctic Survey (BAS), Scientific Committee for Antarctic Research (SCAR), Universities (Bristol, Hull, Liverpool, and Oxford University) and the Natural History Museum (NHM), London.

This project was part of the wider SCAR biological research programme - State of the Antarctic Ecosystem (AntEco). This programme focuses its research on past and present patterns of biodiversity across the Southern Ocean. The broad objectives of the programme is to increase knowledge of biodiversity from genes to ecosystems along with species diversity to infer conservation and management of Antarctic ecosystems using multidisciplinary research approaches in five sectors, led by international scientists:

• Spatial Ecology (Huw Griffiths, British Antarctic Survey)
• Molecular Ecology and Evolution (Jan Strugnell, Latrobe University, Australia)
• Eco informatics and System Biology (Alison Murray, Desert Research Institute, USA)
• Paleoecology (Dominic Hodgson, British Antarctic Survey)
• Impacts, trends and conservation (Annick Wilmotte, University of Liège, Belgium)

SO-AntEco contributes to helping meet these research programmes objectives.

Project Aims and Objectives

The Commission for Conservation of Antarctic Marine Living Resources (CCAMLR) closed all finfish fisheries around South Orkney in 1989. In 2009 they established the South Orkney Islands Southern Shelf Marine Protected Area (SOISS MPA), the first designated MPA within the high seas.

SO-AntEco investigated diversity inside and outside the SOISS MPA to understand species distribution and composition around the Orkney Islands. The main objectives include:

• To find and identify seafloor animals from around the South Orkney Islands and to name any species new to science.
• To detect any significant differences between the types of species and numbers of animals in different habitats.
• To identify species that are indicative of specific habitat types to help with future habitat mapping.
• To map all vulnerable species found and to report their presence and distribution to relevant stakeholders such as CCAMLR.

Fieldwork involved one cruise on the RRS James Clark Ross JR15005 (February 2015) lead by Principal Scientist, Huw Griffiths, using instrumentation such as swath bathymetry, trawling equipment (Agassiz trawl, Rauschert dredge and Epi-benthic sledge) and shallow underwater camera systems to investigate seafloor habitats.

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: