Metadata Report for BODC Series Reference Number 1170371

• 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

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

VEMCO Minilog12-TR temperature logger

Description

The VEMCO Minilog12-TR is a miniature data logger that records temperature at a user programmed time interval. It is housed in a waterproof cylinder and the temperature sensor is mounted on a protruding stainless steel probe.

Specifications

For more information please see the Manufacturer's information sheet.

PO328 Moored Minilogger sensors originators processing document

Data processing

The thermistor inside the Vemco minilogger initially produced an analogue value representing how its electrical resistance changes with temperature. This value was converted into a digital value using an analogue-to-digital (AtoD) converter inside the logger. When the data were downloaded an internally stored calibration was applied to the value to give the temperature in °C and the raw digital output as AtoD. Next, the data were converted from binary to ASCII format by the data originator. Data files supplied to BODC included both the digital temperature value as well as the raw digital output. The originator also supplied suggested correction factors for data from some of the loggers (summarised below). These were calculated by the originator to maintain a decreasing temperature-depth profile. The corrections have not been applied to the data.

Corrections supplied with the data

PO328 Moored VEMCO Minilogger Sensor Processing undertaken by BODC

Data were received by BODC in ASCII files for each sensor deployed. The series were reformatted to internal BODC format using established procedures. The following table details mapping of variables to BODC parameter codes.

Parameters to be processed further

Parameters not to be processed further

The raw digital output of the sensor supplied by the originator has been archived and is available on request if required.

BODC Quality Control

The reformatted data were visualised using BODC in-house software. Suspect data were marked by adding an appropriate quality control flag, and missing data marked by both setting the data to an appropriate absent data value and setting the quality control flag.

Project Information

No Project Information held for the Series

Data Activity or Cruise Information

Data Activity

PO328 East temperature logger mooring

Deployment and recovery

The temperature logger array was deployed and recovered from FS Poseidon cruise PO328.

The mooring was deployed from the afterdeck using the A-frame. The sub-surface buoyancy is deployed first followed by the mooring wire, instruments being attached at pre-marked intervals on the wire. The MORS release is attached to the bottom end of the wire followed by the anchor clump which is cut free when the ship is on station. The ascent rate of the mooring was estimated as 100 m min^-1.

Recovery was over the port side with the strayline attached to the sub-surface buoy being grappled first and the buoy winched onboard. This was then unshackled and the mooring wire attached to the winch. As the wire was wound in the Minilogs were removed one by one until finally the Oceano release was brought onboard.

Mooring setup

The moorings consisted of a 50 m mooring wire attached to a 500 kg anchor clump via an Oceano transponding release. Buoyancy was provided by a syntactic barrel buoy. Each had a 15 m stray line and pickup float to aid recovery. Vemco Minilog temperature recorders were attached using cable ties and PVC tape at 4 m intervals along the mooring wire. In addition a Seabird MicroCAT (temperature, conductivity and pressure) recorder was deployed at the deepest point; nominally 4 m above the bed. The Minilog sampling interval, either two minutes or four minutes, was determined by the memory capacity of the individual loggers.

Rig description

*The originator was unable to download the data from this logger.

POL - Proudman Oceanographic Laboratory, Liverpool
UKORS - UK Ocean Research Services

Related Data Activity activities are detailed in Appendix 1

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:

Appendix 1: PO328_East

Related series for this Data Activity are presented in the table below. Further information can be found by following the appropriate links.

If you are interested in these series, please be aware we offer a multiple file download service. Should your credentials be insufficient for automatic download, the service also offers a referral to our Enquiries Officer who may be able to negotiate access.