Metadata Report for BODC Series Reference Number 1359838

• 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 Clark Ross Cruise AMT14 (JR20040428) - Underway Meteorology Data Quality Report

Some spikes and periods of data were flagged suspect for the True wind speed and wind direction, EWDASS01 and EWSBSS01 respectively.

Values that exceeded the parameter, IRRDSSMS, Limit For Detection (LFM) were automatically flagged as suspect 'M', with some additional high value spikes also flagged.

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

Kipp and Zonen PAR Lite Photosynthetically Active Radiation sensor

An atmospheric radiometer that measures photosynthetically active radiation (PAR) by means of a Teflon diffuser, an optical interference filter and a photo-diode detector. The sensor measures the PAR received over the entire hemisphere and the diffuser's sensitivity is proportional to the cosine of the angle of incidence of the incoming radiation. The optical filter has a spectral response of 400-700 nm (PAR wavelengths) and the photodiode creates a voltage output that is proportional to the incoming radiation.

Specifications

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

Kipp and Zonen SP Lite and SP Lite2 Silicon Pyranometer

An atmospheric pyranometer that measures solar radiation over the range 400-1100 nm by means of a silicon photo-diode detector mounted in a diffuser. The sensor measures the radiation received over the entire hemisphere and the diffuser's sensitivity is proportional to the cosine of the angle of incidence of the incoming radiation. The photodiode creates a voltage output that is proportional to the incoming radiation. The SP Lite2 supersedes the SP Lite and features an improved sensitivity and faster response time than its predecessor.

Specifications

Further details can be found in the manufacturer's specification sheets for the SP Lite and SP Lite2.

RRS James Clark Ross Cruise AMT14 (JR20040428) - Underway Meteorology Instrumentation Document

Th following instruments were used to obtain meteorological measurements:

Where two sensors were used they are physically mounted in close proximity to each other.

CSLRR1XS was produced by merging data from two solar radiation channels.

Rotronic Precision meteorology probes for relative humidity and temperature: MP100A and MP400A series

The MP100A and MP400A series probes comprise a platinum (Pt100) resistance thermometer (with direct or linear output signal) and a Rotronic HYGROMER-C94 humidity sensor.

Instruments from the two series function in the same manner, although the the MP100A series produces voltage output while the MP400A series produces a current output (amps). Differences between the various models in each series are restricted to operational temperature ranges, supply voltages and humidity output signals.

The following specifications are common to all MP100A and MP400A series probes:

Differences between the models are detailed below:

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

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.

Vector Instruments cup anemometer

Instrument used to measure wind speed. The model is unknown. It is assumed to consist of a 3-cup rotor, a precision ball-race mounted shaft and internal modules and components to provide electrical output signals. The outline and mechanical design of Vector Instruments cup anemometers, common to the A100 series, has remained largely unchanged since the introduction of the original Porton Anemometer in 1972.

Vector Instruments wind vane

Instrument used to measure wind direction. The model is unknown. It is assumed to consist of a free-rotating fin that is mounted on a shaft and internal modules and components to provide electrical output signals.

Trimble 4000DS Global Positioning System receiver

The Trimble 4000DS Differential Surveyor is similar to the 4000RS (a Maxwell-based receiver that is oriented toward precision positioning applications. It is intended for use as a DGPS base station, generating RTCM-104 corrections). The 4000Ds can apply RTCM-104 corrections to the satellite data it receives in order to generate accurate position fixes in real time.

RRS James Clark Ross Cruise AMT14 (JR20040428) - Underway Meteorology Processing Document

Originator's Data Processing

The raw data were logged every second to the SCS logging system. The latitude and longitude navigation data originated from the Trimble 4000DS Trimble Surveyor system using Marine Star differential corrections.

The meteorological instruments were located high up on the ship's foremast (approximately 22 m above sea level).

Where two sensors were used they were physically mounted in close proximity to each other.

The data were submitted to BODC in ASCII output from the BAS SCS system for post-cruise processing and data banking.

BODC Data Processing

Reformatting

Data from the full-resolution SCS files were transferred to BODC's NetCDF format QXF under the BODC Underway Data System (BUDS). The transfer involved reducing the data to 60 second intervals.

Data processing, correction and calibration

Navigational data were available from three different systems on the JCR. These were screened in order to select the best quality data for the primary navigation channels. The data from the Trimble GPS system were consistently good and showed no spikes.

A program was run which located any null values in the latitude and longitude channels and checked to ensure that the ship's speed did not exceed 15 knots. There was 1 speed check failures in the Trimble navigation data and 2 small gaps. These points were screened again to look for improbable spikes which were flagged as null. The gaps were then filled using linear interpolation.

Relative wind speed and direction were logged from the meteorological package during the cruise. The anemometer was positioned with 0 degrees at the ship's bow. The ship's speed relative to the ground was calculated at BODC using the ship's navigational information and the ship's heading. The speed and heading were then used to correct the wind data for the effect of the ship's movement. Absolute wind speed and direction channels were created.

Screening

Each data channel was inspected on a graphics workstation and any spikes or periods of dubious data were flagged. The power of the workstation software was used to carry out comparative screening checks between channels by overlaying data channels. A map of the cruise track was simultaneously displayed in order to take account of the oceanographic context.

Values that were outside the parameters designated limits for detection were automatically flagged 'M' with some flagged in close proximity that were close to the LFM.

Project Information

The Atlantic Meridional Transect - Phase 2 (2002-2006)

Who was involved in the project?

The Atlantic Meridional Transect Phase 2 was designed by and implemented by a number of UK research centres and universities. The programme was hosted by Plymouth Marine Laboratory in collaboration with the National Oceanography Centre, Southampton. The universities involved were:

• University of Liverpool
• University of Newcastle
• University of Plymouth
• University of Southampton
• University of East Anglia

What was the project about?

AMT began in 1995, with scientific aims to assess mesoscale to basin scale phytoplankton processes, the functional interpretation of bio-optical signatures and the seasonal, regional and latitudinal variations in mesozooplankton dynamics. In 2002, when the programme restarted, the scientific aims were broadened to address a suite of cross-disciplinary questions concerning ocean plankton ecology and biogeochemistry and the links to atmospheric processes.

The objectives included the determination of:

• how the structure, functional properties and trophic status of the major planktonic ecosystems vary in space and time
• how physical processes control the rates of nutrient supply to the planktonic ecosystem
• how atmosphere-ocean exchange and photo-degradation influence the formation and fate of organic matter

The data were collected with the aim of being distributed for use in the development of models to describe the interactions between the global climate system and ocean biogeochemistry.

When was the project active?

The second phase of funding allowed the project to continue for the period 2002 to 2006 and consisted of six research cruises. The first phase of the AMT programme ran from 1995 to 2000.

Brief summary of the project fieldwork/data

The fieldwork on the first three cruises was carried out along transects from the UK to the Falkland Islands in September and from the Falkland Islands to the UK in April. The last three cruises followed a cruise track between the UK and South Africa, only deviating from the traditional transect in the southern hemisphere. During this phase the research cruises sampled further into the centre of the North and South Atlantic Ocean and also along the north-west coast of Africa where upwelled nutrient rich water is known to provide a significant source of climatically important gases.

Who funded the project?

Natural Environment Research Council (NERC)

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: