Metadata Report for BODC Series Reference Number 2201154

• 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

The port and starboard TIR sensors are offset by 8.6% which is well above the 2.5% instrumental uncertainty specified in the sensor calibration certificates. The starboard sensor appears to be compromised as it was last calibrated eighteen months prior to the cruise whereas the port sensor calibration was only six months prior. For this reason, the entire starboard TIR channel has been flagged and should be used with caution (BODC assessment).

JC191 Underway Meteorology Quality Control Report

Wind sensors

The wind data are of good quality overall but there are periods in this series where wind shielding is apparent. This was predominantly when the wind was blowing from 250-300° from the bow when the anemometer is partially blocked by the ship superstructure. Some instances of artificial acceleration and spiking were observed and flagged accordingly (BODC assessment).

Light sensors

The port and starboard PAR data look good and compare quite well. Quality control flags have been applied to instances of transient shading in both the port and starboard PAR sensors. The port TIR sensor has flags applied to instances of transient shading and appear to be of good quality overall. However, the port and starboard TIR sensors are offset by 8.6% which is well above the 2.5% instrumental uncertainty specified in the sensor calibration certificates. The starboard sensor appears to be compromised as it was last calibrated eighteen months prior to the cruise (port sensor was six months prior). For this reason, the entire starboard TIR channel has been flagged (BODC assessment).

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

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.

JC191 Underway Meteorology Instrumentation

Instrumentation

The meteorological suite of sensors was located on the forecastle deck, between 17.55 and 19.4 m above sea level. The anemometer orientation was 0° on the bow.

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

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 PTB110 barometer

An industrial, analog barometer which uses a silicon capacitive sensor (BAROCAP). The sensor produces either frequency or voltage output and is mountable on a (35 mm wide) DIN rail.

Operating ranges (1 hPa = 1 mbar)

General

Accuracy

* Defined as ±2 standard deviation limits of end-point non-linearity, hysteresis error or repeatability error.
** Defined as ±2 standard deviation limits of inaccuracy of the working standard including traceability to NIST.
*** Defined as the root sum of the squares (RSS) of end-point non-linearity, hysteresis error, repeatability error and calibration uncertainty at room temperature when using voltage output.

More detailed information can be found in the manufacturer's data sheet and user's guide.

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.

JC191 Underway Meteorology Data Processing Procedures

Originator's Data Processing

The data were logged by the TECHSAS (TECHnical and Scientific sensors Acquisition System) system into daily NetCDF files. The TECHSAS system is used as the main data logging system on NMF-SSS operated reserach vessels. Data were processed by the originator using the National Oceanography Centre MSTAR data processing routines into NetCDF format. These MSTAR (NetCDF) files were provided to BODC and used for BODC processing. Please refer to the JC191 cruise report for more information.

Files delivered to BODC

BODC Data Processing

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

oceanlogger_jr18002_01_medav_clean_cal.nc

surfmet_jc191_trueav.nc

*-*-MET-SURFMETv3.SURFMETv3

All data expressed at measurement altitude.

Calibrations

Field Calibrations

No field calibrations were applied to the data at BODC.

Manufacturers Calibrations

Air pressure

A manufacturer's calibration was not applied to the Vaisala PTB110 barometer because there was no significant offset reported on the certified calibration certificate.

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:

Relative 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 following the Shipboard Automated Meteorological and Oceanographic System (SAMOS) method, thus obtaining the BODC derived absolute wind speed and direction parameters, with codes EWSBSS01 and EWDASS01 respectively.

Relative humidity and air temperature

Manufacturer's calibrations were not applied to the Vaisala HMP45AL temperature and humidity probe data because there were no significant offsets reported on the certified calibration certificate.

Screening

All reformatted data were visualised using the in-house EDSERPLO software. Where calibrations had been applied, only the calibrated versions of those parameters were screened. Suspect data were marked by adding an appropriate quality control flag.

Project Information

Marine LTSS: CLASS (Climate Linked Atlantic Sector Science)

Introduction

CLASS is a five year (2018 to 2023) programme, funded by the Natural Environment Research Council (NERC) and extended until March 2024.

Scientific Rationale

The ocean plays a vital role in sustaining life on planet Earth, providing us with both living resources and climate regulation. The trajectory of anthropogenically driven climate change will be substantially controlled by the ocean due to its absorption of excess heat and carbon from the atmosphere, with consequent impacts on ocean resources that remain poorly understood. In an era of rapid planetary change, expanding global population and intense resource exploitation, it is vital that there are internationally coordinated ocean observing and prediction systems so policy makers can make sound evidence-based decisions about how to manage our interaction with the ocean. CLASS will underpin the UK contribution to these systems, documenting and understanding change in the marine environment, evaluating the impact of climate change and effectiveness of conservation measures and predicting the future evolution of marine environments. Over the five-year period CLASS will enhance the cost-effectiveness of observing systems by migrating them towards cutting edge autonomous technologies and developing new sensors. Finally, CLASS will create effective engagement activities ensuring academic partners have transparent access to NERC marine science capability through graduate training partnerships and access to shipborne, lab based and autonomous facilities, and modelling capabilities.

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: