Metadata Report for BODC Series Reference Number 1174058


Metadata Summary

Data Description

Data Category Bathythermograph -expendable
Instrument Type
NameCategories
Lockheed Martin Sippican T-5 XBT probe  bathythermographs; water temperature sensor
Instrument Mounting research vessel
Originating Country United Kingdom
Originator Dr Claire Waluda
Originating Organization British Antarctic Survey
Processing Status banked
Project(s) BAS Long Term Monitoring and Survey
GSAC
 

Data Identifiers

Originator's Identifier T5_00029
BODC Series Reference 1174058
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 2009-01-03 12:11
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval 1.0 metres
 

Spatial Co-ordinates

Latitude 53.32444 S ( 53° 19.5' S )
Longitude 37.77298 W ( 37° 46.4' W )
Positional Uncertainty 0.0 to 0.01 n.miles
Minimum Sensor Depth 2.0 m
Maximum Sensor Depth 1830.5 m
Minimum Sensor Height -
Maximum Sensor Height -
Sea Floor Depth -
Sensor Distribution Variable common depth - All sensors are grouped effectively at the same depth, but this depth varies significantly during the series
Sensor Depth Datum Instantaneous - Depth measured below water line or instantaneous water body surface
Sea Floor Depth Datum -
 

Parameters

BODC CODE Rank Units Short Title Title
ACYCAA01 1 Dimensionless Record_No Sequence number
DEPHCV01 1 Metres Depth Depth below surface of the water body by computation from probe free-fall time using unspecified algorithm
SVELCV01 1 Metres per second Cmpval Sound velocity in the water body by computation from temperature and salinity by unspecified algorithm
TEMPET01 1 Degrees Celsius XBTTmp Temperature of the water body by expendable bathythermograph (XBT)
 

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

Quality report for James Clark Ross cruise JR20081228 (JR188) XBT data

All casts were screened and M flags applied to cycles where suspect data were identified. The following series/cycles were flagged:

Series reference Cycles Comments
51000 648-2904 Constant/suspect values
51100 873-2904 Constant/suspect values
51200 570-2905 Constant/suspect values
51900 615-2903 Constant/suspect values
52000 416-2904 Constant/suspect values
52100 all cycles flagged values are suspect
52300 1076-2904 Constant/suspect values
52400 564-2904 Constant/suspect values
52500 588-2904 Constant/suspect values
52600 569-2905 Constant/suspect values
52700 556-2905 Constant/suspect values
53400 580-2905 Constant/suspect values
53500 175-2904 Constant/suspect values

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

Instrument description

Lockheed Martin Sippican T-5 XBT Probe

The Expendable Bathythermograph system uses a sea water ground. As soon as an electrode within the nose of the expendable probe makes contact with the water, the circuit is complete and temperature or sound velocity data can be telemetered to the ship-board data processing equipment. The T-5 XBT Probe can be used within a maximum depth of 1830 m, with a rated ship speed of 6 knots and has a vertical resolution of 65 cm.

Manufacturer specifications can be found here

BODC processing document for XBT data

BODC Processing

The files were sent to BODC in .EDF format, which can be opened with a text editor. No processing was carried out at BODC.

The files were converted to BODC internal format (QXF) using BODC established procedures. There was no need to apply unit conversions as the originator's units were equivalent to the units stored on BODC's vocabulary dictionary.

The following table shows how the variables within the originator's files were mapped to appropriate BODC parameter codes:

Originator's Parameter Name Units Description BODC Parameter Code Units
Depth m Depth below surface of the water body by computation from probe free-fall time using unspecified algorithm DEPHCV01 m
Temperature °C Temperature of the water body by expendable bathythermograph (XBT) TEMPET01 °C
Sound Velocity m s -1 Sound velocity in the water body by computation from temperature and salinity by unspecified algorithm SVELCV01 m s -1

Reformatted XBT data were visualised using the in-house graphical editor EDSERPLO. Quality control flags were applied to data as necessary.

Originator's processing document for JR20081228 (JR188) XBT data

A total of 30 expendable bathymetry thermographs (XBT) were launched during cruise JR20081228 (JR188) whilst the ship was sailing. The speed was reduced from 10 to 6 knots to allow for data acquisition. The data were transferred to a PC via a USB interface that provided the communication with the XBT launcher.

The data were were obtained with T5 Sippican probes and were not processed or calibrated by the originator.


Project Information

BAS Long Term Monitoring and Survey

Introduction

The Long Term Monitoring and Survey project (LTMS) has been running since the British Antarctic Survey (BAS) was created. This project is one of the BAS core projects, with several groups of scientists collecting various types of data e.g biological, geological, atmospheric, among others.

Data collection is achievable through a wide scope of instruments and platforms, e.g. the Antarctic research stations, autonomous instrument platforms deployed on or from BAS research ships, BAS aircrafts, satellite remote sensing and others.

Scientific Objectives

This project was implemented in order to measure change and variability in the Earth system. Its long term duration allows for the monitoring of processes that could be missed in shorter term studies and experiments. The data collected is also used to check and improve the reliability of models used to stimulate and predict the behavior of the Earth system.

The main objectives are:

Data Availability

The data sets obtained through this project are available to the academic community.


Global Science in an Antarctic Context (GSAC)

Introduction

GSAC is the British Antarctic Survey research programme from 2005 to 2009, it encompasses 8 programmes, including 18 projects as well as long-term monitoring and survey activities.

This programme was created to fulfill BAS vision of becoming, by 2012, the leading international centre making use of the of the Antarctic and the Southern Ocean. This research programme consists of an integrated set of inter-disciplinary research, monitoring and survey activities designed to extract new knowledge from the Antarctic, provide information to policy makers and benefit society in general.

GSAC supports the Natural Environment Research Council (NERC) strategy Science for a Sustainable Future and contributes to other programmes such as the World Climate Research programme, the International Geosphere-Biosphere Programme, the Convention on Biological Diversity, the Scientific Committee for Antarctic Research and the International Polar Year 2007-2009.

The programme's components are highly interconnected and its content makes full use of BAS Antarctic infrastructure and builds on previous BAS research, survey and monitoring, whilst also exploring new areas.

The programmes contributing to GSAC are:

More detail is provided in each programme document.


Data Activity or Cruise Information

Cruise

Cruise Name JR20081228 (JR188)
Departure Date 2008-12-28
Arrival Date 2009-01-06
Principal Scientist(s)Claire Waluda (British Antarctic Survey)
Ship RRS James Clark Ross

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