Metadata Report for BODC Series Reference Number 1902223

• 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

DISCOVERY 2010 Cruise RRS James Clark Ross JR20071230 (JR177, JR205, JR207) Underway Meteorology Data Quality Document

Negative data values were identified during night periods of the time series. These instances have been flagged M as they are likely to be an artefact of the sensor's own radiation at night.

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 & Zonen Photosynthetically Active Radiation Quantum Sensor PQS1

The PQS1 is an atmospheric radiometer designed to measure incident radiation at photosynthetically active radiation (PAR) wavelengths. It incorporates a diffuser with an excellent directional (cosine) response and a silicon photodiode detector.

If used in field research applications, the PQS1 can be connected with the METEON handheld display unit, which also as data-logging capability. For permanent installations, it can be connected to the LOGBOX SD data logger.

Specifications

A link to the PQS1 specification sheet can be found here: PQS1 Spec 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

Rotronic Hygromet MP102H and MP402H temperature and humidity probes

This meteorological probe measures humidity and temperature with the plug-in HygroClip HC2-S3 sensor module, and can also be equipped with a signal conditioned Pt100 temperature probe.

The two models differ in that the MP102H produces a voltage output while the MP402H produces a current output. Other characteristics are common to both models.

The specification sheet can be accessed here Rotronic MP102H and MP402H.

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.

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

DISCOVERY 2010 Cruise RRS James Clark Ross JR20071230 (JR177, JR205, JR207) Underway Meteorology Instrumentation Document

Meteorological measurements were performed by several sensors located at the meteorological mast. All instruments were located at a height of 20 m except the anemometer which was located 22.5 m above the water. The secondary air temperature, air pressure and relative humidity sensors were not logging during the cruise.

DISCOVERY 2010 Cruise RRS James Clark Ross JR20071230 (JR177, JR205, JR207) Underway Meteorology Processing Procedures Document

Originator's Data Processing

Data processing was done by the originator in Unix and Matlab using modified versions of programs developed by Mike Meredith (BAS) and then read over into netCDF format. Procedures included data loading, setting unrealistic values to NaN and linear interpolation to fill data gaps.

All instruments, except the anemometer, which was on a mast 22.5 m above sea level, were located on the ship's meteorological mast, the sensors were placed side by side, 20 m above sea level.

Meteorological data originated from duplicate sensors located on the RRS James Clark Ross meteorological mast. The originator sent data in 45 files containing wind direction and speed, and one file containing PAR.

Other meteorological parameters, as air temperature, air pressure, relative humidity and TIR were retrieved from data processed by the BAS Polar Data Centre (BAS-PDC). The processing procedures include:

• check for duplicate dates and times
• standardising time
• check for gaps in data
• check data against defined thresholds
• flagging
• unit conversion

Originator's files contain data from 01 January 2008 00:00 hours to 13 February 2008 23:59 hours. BAS-PDC files cover a period from 30 December 2007 00:00 hours to 15 February 2008 23:59 hours.

File delivered to BODC

BODC Data Processing

The files mentioned above were selected for data banking as they contain the best version of processed meteorological parameters. Data were banked at BODC following standard data banking procedures, including reduction through averaging, checking meteorological channels for improbable values, working out absolute wind speed and direction, and screening the data for anomalous values. The originator's variables were mapped to appropriate BODC parameter codes as follows:

jr177_ocl_exactsec

anemom001 to anemom045

JR177_alldataCal_1min

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

The meteorological data were collected with two sets of instruments. Data from both sensors, primary and secondary, were transferred and visually checked.

Absolute wind speed and direction

Relative wind speed and direction were corrected for the ship's heading and speed using the gyrocompass heading, ship velocities (calculated at BODC from the main positional channels) and an anemometer orientation of 0° on the bow.

EWSBSS01 and EWDASS01 were assigned M flags in different instances:

• to all cycles flagged in ERWDSS01 and ERWSSS01
• to sudden changes in wind speed and direction identified during screening

PAR and TIR

N flags were applied to null values on all channels. Slightly negative data was identified during night periods. These instances have been flagged M as they might be an artefact of the sensor's own radiation at night.

Air Pressure

Both channels were screened and they exhibit a similar quality.

Air Temperature and Relative Humidity

All channels were screened and it was clear that the secondary sensors were not logging during the cruise. The final file contains data for CRELZZ01 and CDTAZZ01 only.

Project Information

DISCOVERY 2010

DISCOVERY 2010 will investigate and describe the response of an ocean ecosystem to climate variability, climate change and commercial exploitation. The programme builds on past studies by BAS on the detailed nature of the South Georgia marine ecosystem and its links with the large-scale physical and biological behaviour of the Southern Ocean.

The aim is to identify, quantify and model key interactions and processes on scales that range from microscopic life forms to higher predators (penguins, albatrosses, seals and whales), and from the local to the circumpolar.

Objectives

Assess the links between the status of local marine food webs and variability and change in the Southern Ocean. Develop a linked set of ecosystem models applying relevant marine physics and biology over scales from the local to that of the entire Southern Ocean.

Relevance to Global Science

Ocean ecosystems play a crucial role in maintaining biodiversity, in depositing carbon into the deep ocean, and as a source of protein for humans. However, fishing and climate change are having significant and often detrimental effects. To predict the future state of ocean ecosystems we must develop computer models capable of simulating biological and physical processes on a range of scales from the local to an entire ocean. Developing such predictive models is crucial to the sustainable management of world fisheries and requires integrated analyses of the way whole ecosystems work. DISCOVERY 2010 aims to take this work forward and at the same time help manage the South Georgia and South Sandwich Islands maritime zone. We will do this through providing information on the state of the ecosystem to the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR), the international body that manages sustainable fishing in the Southern Ocean.

Delivering the Results

DISCOVERY 2010 will undertake an integrated programme of shipboard and land-based field studies of the marine food web, combined with modelling. We will pay particular attention to critical phases in the life cycles of key species, and to examining interactive effects in food webs. Interacting biological and physical processes will be modelled across a range of spatial scales to significantly improve our representation of the ocean ecosystem, upon which sustainable management and the prediction of future climate change can be based. DISCOVERY 2010 will link to BIOFLAME, ACES, and COMPLEXITY, two international programmes, and to a collaborative programme with the University of East Anglia on the role of the Southern Ocean in the global carbon cycle.

Component Projects

• DISCOVERY-OEM: Ocean Ecosystems and Management
• DISCOVERY-FOOD-WEBS: Scotia Sea FOOD-WEBS
• DISCOVERY-FLEXICON: FLEXIbility and CONstraints in life histories
• DISCOVERY-CEMI: Circumpolar Ecosystems; Modelling and Integration

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: