Metadata Report for BODC Series Reference Number 86546

• 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

Public domain 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.

The recommended acknowledgment is

"This study uses data from the data source/organisation/programme, provided by the British Oceanographic Data Centre and funded by the funding body."

Narrative Documents

Bissett-Berman 9060 Salinity Temperature and Depth

The B-B 9060 STD measured salinity, temperature and depth and whose analogue output was in graphical form. The plots created were of salinity and temperature versus depth which had to be manually digitised.

RRS Discovery Cruise 69 STD Data Documentation

Introduction

Documentation for STD data collected on RRS Discovery Cruise 69 (January - March 1975) by the Department of Oceanography, University of Liverpool, Liverpool, U.K., under the direction of P. Hughes.

Instrumentation,

The instrument used was the University of Liverpool Bissett Berman Salinity-Temperature-Depth system type 9006, with a Rosette water sampler attached to the wire above it. The data output from each STD lowering and raising was automatically recorded in digital and analogue form. Data storage was effected on paper tape and separately on disk on the ship's IBM 1800 computer.

Sampling

There were some troublesome faults on the salinity sensor which produced occasional loss of signal when hauling in. The intermittent nature of the malfunction made it difficult to locate, but the problem was eventually resolved by changing the interconnecting harness between the mixer and sensor units and by making good a suspect connection on a circuit board in the salinity unit. Despite these difficulties STD casts were made successfully at all the proposed positions. An IOS water sampling bottle with associated reversing thermometers was located as near to the probe as possible on each cast for calibration purposes. Consistent calibrations with the makers specified tolerances were determined. The rosette multi sampler was initially used for salinity calibrations and to take samples at standard depths for chemical determinations. Its use was eventually discontinued in favor of separate bottle casts because it suffered from intermittent failures and bottle leakage.

Stations were identified by their 4 digit Discovery station number. Time series measurements were taken at 2 stations. These were at station 8765, where STD dips were made to 300m every hour between 06:30h and 18:30h on 24 Feb 1975, and station 8772, where STD dips were made every hour to 300m between 06:30h and 18:30h on 26 February 1975. For stations 8765 and 8772 individual dips are identified by the 4 digit Discovery station number, followed by the sequence number of the dip (from 01 to 13).

Data Quality and Calibration

The absolute accuracies of the temperature and salinity measurements were checked by comparison with a series of temperature measurements and salinity samples obtained with reversing thermometers and water bottles over the course of the cruise. The comparisons using the reversing thermometers showed that the temperature sensor was operating within the manufacturer's specified tolerances and no corrections were necessary. For the salinity 0.03ppt was added to all the observations taken during the first leg of the cruise (21 January - 18 Febuary 1975) and 0.016ppt on the second leg (18 Febuary - 18 March 1975). After calibration against the water bottle observations the STD data were despiked, smoothed and interpolated to 1m depth intervals.

References

RRS Discovery Cruise 69, 21 January - 18 March 1975.
Upwelling off north- west Africa. Institute of Oceanographic Sciences Cruise Report No. 51. 1977.

Brockmann, C., Hughes, P. and Tomczak, M. (1977).
Data report on currents, winds and stratification in the North-west African upwelling region during early 1975. Berichte aus dem Institute fur Meereskunde No. 32.

Project Information

No Project Information held for the Series

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: