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Metadata Report for BODC Series Reference Number 168909


Metadata Summary

Data Description

Data Category CTD or STD cast
Instrument Type
NameCategories
Christian Albrechts University of Kiel Multisonde CTD profiler  CTD; water temperature sensor; salinity sensor
Instrument Mounting research vessel
Originating Country Germany
Originator -
Originating Organization Institute of Marine Sciences, Kiel (now GEOMAR Helmholtz Centre for Ocean Research, Kiel (West Shore Campus))
Processing Status banked
Online delivery of data Download available - Ocean Data View (ODV) format
Project(s) JASIN
 

Data Identifiers

Originator's Identifier PLANET/51028
BODC Series Reference 168909
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 1978-08-30 11:55
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval -
 

Spatial Co-ordinates

Latitude 58.90830 N ( 58° 54.5' N )
Longitude 12.39000 W ( 12° 23.4' W )
Positional Uncertainty Unspecified
Minimum Sensor or Sampling Depth 1.49 m
Maximum Sensor or Sampling Depth 105.48 m
Minimum Sensor or Sampling Height 1535.52 m
Maximum Sensor or Sampling Height 1639.51 m
Sea Floor Depth 1641.0 m
Sea Floor Depth Source -
Sensor or Sampling Distribution Variable common depth - All sensors are grouped effectively at the same depth, but this depth varies significantly during the series
Sensor or Sampling Depth Datum Instantaneous - Depth measured below water line or instantaneous water body surface
Sea Floor Depth Datum Unspecified -
 

Parameters

BODC CODERankUnitsTitle
PRESPR011DecibarsPressure (spatial coordinate) exerted by the water body by profiling pressure sensor and correction to read zero at sea level
SSALPR011Parts per thousandSalinity of the water body by conductivity cell
TEMPST011Degrees CelsiusTemperature of the water body by CTD or STD

Definition of Rank

  • Rank 1 is a one-dimensional parameter
  • Rank 2 is a two-dimensional parameter
  • Rank 0 is a one-dimensional parameter describing the second dimension of a two-dimensional parameter (e.g. bin depths for moored ADCP data)

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

Christian Albrechts University of Kiel Multisonde CTD profiler

A prototype conductivity-temperature-pressure profiler developed in the 1970s by what was then the Institute for Applied Physics of Kiel University. The instrument could measure up to six parameters in total, including sound velocity and light attenuation by means of an auxiliary light sensor. The unit was used by the then Institute for Marine Science, Kiel.

Specifications

  Pressure Temperature Conductivity
Range 600 or 6000 dbar -2 to 40 °C 5 to 55 mmho cm-1
Accuracy ± 0.01% ± 0.01 °C ± 10 µmho cm-1

WFS Planet Cruise 10/78 CTD Data Documentation

Introduction

Documentation for the CTD data collected on W.F.S. Planet cruise 10/78 15 August 1978 - 14 September 1978, under the direction of G. Siedler, Institut für Meereskunde an der Universität Kiel, Germany.

Instrumentation

The instrument used was a Multisonde CTD, which measured hydrostatic pressure, temperature and electrical conductivity. The initial sampling rate was 16Hz and the lowering rate between 30 to 40 metres/minute.

Calibration

In order to check the calibration during the experiment a Nansen bottle with two protected reversing thermometers was attached to the cable close to the underwater unit. Various combinations of three thermometers were used. Seventeen water samples were collected from about 200m. In addition, 20 samples were taken from lowerings of the Bathysonde CTD on this cruise.

It was assumed that a proper re-calibration could be achieved by determining the offset in temperature and conductivity at this depth level. The pressure offset was found by reading the pressure value at the sea surface. There was no time dependence of these re-calibration terms.

The results of the re-calibration analysis are summarised in the table below. The reversing thermometers were checked after the cruise and some of them had changed. A comparison with other instruments showed that the best temperature calibration was achieved by using an offset of -0.014 °C. The salinity measurements of the Nansen samples were carried out using a Beckman RS7B lab and an Autosal 8400 salinometer. 27 pairs of water samples from one Nansen bottle showed no differences between those two instruments. Conductivity was calculated from the salinity values by an iterative reversal of Fofonoff's (1974) formula using Newton's formula (Peters 1976).

Due to the slow response of the Multisonde thermometers compared to the conductivity sensors, spikes occurred in the salinity profiles. The thermometer time constants were changed in the calculations to optimise the spike reduction. After clipping remaining spikes in salinity, a running mean over about 0.5 dbar was taken. The data were then interpolated to 0.5 dbar increments and again a running mean over 1.5 dbar was calculated.

Re-calibration data for Multisonde CTD

CTD pressure reading at the sea surface (600 dbar) -4.1 dbar
CTD pressure reading at 6000 dbar -22.0 dbar
Mean difference between reversing thermometer and CTD temperature reading (T(NANSEN)-T(CTD)) -0.026 °C (±0.012 °C)
Mean temperature difference between two reversing thermometers in a Nansen bottle -0.015 °C (±0.009 °C)
Mean difference between Nansen bottle and CTD conductivity reading (C(NANSEN)-C(CTD)) +0.0134 10-3 S/cm(±0.0069 10-3 S/cm)
Time constant of the thermometer 150 milliseconds

The final data series are at 0.5 dbar intervals, this information has not been included with the series header details.

References

Peters, H. 1978.
A compilation of CTD and profiling current meter data from GATE 1974, FS Meteor and WFS Planet. 'Meteor' Forschungsergebnisse A No.20 p49-80.

Fofonoff, N.P., Hayes, S.P. and Millard Jr., R.C. (1974).
WHOI/Brown Micro- profiler: Methods of calibration and data handling. WHOI Technical Report No. 74-89, 64pp (unpublished manuscript)

Knoll, M. (1983).
CTD and current profiler data from JASIN 1978. Meteor Forschungsergebnisse, A/B, No.24, p25-40


Project Information

Joint Air Sea Interaction Experiment (JASIN)

The JASIN Project was designed to study the interaction of the atmospheric and oceanic boundary layers with the larger scale motions of the sea and the air.

The primary aims may be summarized as follows:

  1. To observe and distinguish between the physical processes causing mixing in the atmospheric and oceanic boundary layers and relate them to the mean properties of the layers.

  2. To examine and quantify aspects of the momentum and heat budgets in the atmospheric and oceanic boundary layers and fluxes across and between them.

The multiplicity of processes to be sampled necessitated a large experiment and JASIN involved 14 ships and 3 aircraft with more than 50 teams of investigators from 9 countries. Altogether 35 mooring systems were deployed.

The experiment lasted for 2 months from mid-July to mid-September 1978 and comprised 2 intensive measuring periods preceded by a preparatory test period. The project took place in the north Rockall Trough, an area of deep water (1000m - 2000m) several hundred kilometres off the west coast of Scotland.


Data Activity or Cruise Information

Cruise

Cruise Name 10/78
Departure Date 1978-08-15
Arrival Date 1978-09-14
Principal Scientist(s)Gerold Siedler (Institute of Marine Sciences, Kiel)
Ship Planet

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:

Flag Description
Blank Unqualified
< Below detection limit
> In excess of quoted value
A Taxonomic flag for affinis (aff.)
B Beginning of CTD Down/Up Cast
C Taxonomic flag for confer (cf.)
D Thermometric depth
E End of CTD Down/Up Cast
G Non-taxonomic biological characteristic uncertainty
H Extrapolated value
I Taxonomic flag for single species (sp.)
K Improbable value - unknown quality control source
L Improbable value - originator's quality control
M Improbable value - BODC quality control
N Null value
O Improbable value - user quality control
P Trace/calm
Q Indeterminate
R Replacement value
S Estimated value
T Interpolated value
U Uncalibrated
W Control value
X Excessive difference

SeaDataNet Quality Control Flags

The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:

Flag Description
0 no quality control
1 good value
2 probably good value
3 probably bad value
4 bad value
5 changed value
6 value below detection
7 value in excess
8 interpolated value
9 missing value
A value phenomenon uncertain
B nominal value
Q value below limit of quantification