Metadata Report for BODC Series Reference Number 1816997

• 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 Discovery cruise DY072 meteorology quality control report

Light sensors

All PAR and TIR channels display occasional negative readings during night time. This most likely results from excessive loss of radiation after sunset, which suggests that day-time data recorded during cloud cover should also be treated with caution. Another explanation would be that outdated calibrations added an offset to the data. All negative PAR and TIR data were flagged. (BODC assessment)

Wind sensors

Evidence of faint wind shielding was observed in meteorological data when winds were coming from 170-190° relative to the bow. All meteorology channels (except light) were flagged appropriately. (BODC assessment).

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

Gill Instruments Windsonic Anemometer

The Gill Windsonic is a 2-axis ultrasonic wind sensor that monitors wind speed and direction using four transducers. The time taken for an ultrasonic pulse to travel from the North to the South transducers is measured and compared with the time for a pulse to travel from South to North. Travel times between the East and West transducers are similarly compared. The wind speed and direction are calculated from the differences in the times of flight along each axis. This calculation is independent of environmental factors such as temperature.

Specifications

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

Kipp and Zonen Pyranometer Model CM6B

The CM6B pyranometer is intended for routine global solar radiation measurement research on a level surface. The CM6B features a sixty-four thermocouple junction (series connected) sensing element. The sensing element is coated with a highly stable carbon based non-organic coating, which delivers excellent spectral absorption and long term stability characteristics. The sensing element is housed under two concentric fitting Schott K5 glass domes.

Specifications

RRS Discovery cruise DY072 meteorology instrumentation

Instrumentation

The meteorological suite of sensors was located on the forecastle deck, at approximately 17.4 m above sea level. The anemometer orientation was 0° on the bow.

Skye Instruments PAR Energy Sensor Model SKE 510

The SKE 510 is suitable for measuring photosynthetically active radiation (PAR) from natural or artificial light sources. The sensor is fully waterproof and guaranteed submersible to 4m depth, and indoor versions are also available.

The instrument uses a blue-enhanced planar diffused silicon detector to measure energy (in W m^-2) over the 400-700 nm waveband. It has a cosine-corrected head and a square spectral response. The sensor can operate over a temperature range of -35 to 70 °C and a humidity range of 0-100% RH.

Specifications

Vaisala PTB210 Digital Barometer

The basic specifications for this pressure sensor are as follows:

• Manufacturer: Vaisala
• Type: Silicon capacitive sensor
• Model: PTB210
• Range: 900 - 1100 hPa
• Output: 0-5VDC
• Total Accuracy (20°C): ±0.30hPa
• Operating temperature: -40 to +60 deg C
• Weight: 110g
• Certification Ingress Protection: IP65

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

Vaisala Temperature and Relative Humidity HMP Sensors

A family of sensors and instruments (sensors plus integral displays or loggers) for the measurement of air temperature and relative humidity. All are based on a probe containing a patent (HUMICAP) capacitive thin polymer film capacitanece humidity sensor and a Pt100 platinum resistance thermometer. The probes are available with a wide range of packaging, cabling and interface options all of which have designations of the form HMPnn or HMPnnn such as HMP45 and HMP230. Vaisala sensors are incorporated into weather stations and marketed by Campbell Scientific.

All versions operate at up to 100% humidity. Operating temperature ranges vary between models, allowing users to select the version best suited to their requirements.

Further details can be found in the manufacturer's specification sheets for the HMP 45 series, HMP 70 series and HMP 230 series.

RRS Discovery cruise DY072 meteorology data processing procedures

Originator's Data Processing

The data were logged by the TECHSAS (TECHnical and Scientific sensors Acquisition System) version 5.9 data logging system into daily NetCDF files which were provided to BODC for processing. Data was additionally logged into the RVS Level-C format which have been archived at BODC.

Files delivered to BODC

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:

yyyymmdd-090000-MET-DY-SM_DY1.SURFMETv2

yyyymmdd-090000-Light-DY-SM_DY1.SURFMETv2

All data expressed at measurement altitude.

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

Calibrations

Field Calibrations

No field calibrations were applied to the data at BODC.

Manufacturers Calibrations

PAR/TIR

The following manufacturer's calibrations were applied to the PAR and TIR light sensors using:

y (W m ^-2 ) = (a x 10 ⁶ )/b

where 'a' is the raw data in volts and 'b' is the calibration offset (µV per W m ^-2 ) as shown below.

Absolute wind speed and direction

Relative wind speed and direction were corrected for the ship's heading and speed using the POS MV gyro heading, ship velocities (calculated at BODC from the main positional channels) and an anemometer orientation of 0° on the bow, thus obtaining the BODC derived absolute wind speed and direction parameters, with codes EWSBSS01 and ERWDSS01 respectively.

Air pressure

A manufacturer's calibration was not applied to the barometer because there was no significant offset reported on the certified calibration certificate.

Air temperature and humidity

Manufacturer's calibrations were not applied to the temperature and humidity probe because there were no significant offsets reported on the certified calibration certificate.

Project Information

Passive Imaging of the Lithosphere Asthensphere Boundary (PiLAB)

PiLAB is a three-year collaborative research project that aims taims to systematically image the entire length of an oceanic plate, from its birth at the Mid-Atlantic Ridge, to its oldest formation on the African margin, in order to determine the processes and properties that define and strengthen a plate.

Through this, PiLAB will improve global understanding of plate physiology and structure.

The PiLAB project is led by the University of Southampton, school of Ocean and Earth Sciences and is a collaboration between IFM GEOMAR, Germany, the Institute of Earth Physics, IPGP, France, and the universities of California and Bristol. The project received funding from the Natural Environmental Research Council and runs between February 2016 and January 2019 and forms part of the UK contribution to the global GEOTRACES project.

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: