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Metadata Report for BODC Series Reference Number 1763934


Metadata Summary

Data Description

Data Category Hydrography time series at depth
Instrument Type
NameCategories
Sea-Bird SBE 37 MicroCat SM-CT with optional pressure (submersible) CTD sensor series  water temperature sensor; salinity sensor
Instrument Mounting subsurface mooring
Originating Country United Kingdom
Originator Mr Povl Abrahamsen
Originating Organization British Antarctic Survey
Processing Status banked
Online delivery of data Download available - Ocean Data View (ODV) format
Project(s) Ice Sheet Stability (iSTAR) Programme
Ocean2ice (iSTAR A)
 

Data Identifiers

Originator's Identifier MOORING_PIG_N_SBE37_8539
BODC Series Reference 1763934
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 2014-02-18 14:20
End Time (yyyy-mm-dd hh:mm) 2016-02-02 22:39
Nominal Cycle Interval 300.0 seconds
 

Spatial Co-ordinates

Latitude 74.86720 S ( 74° 52.0' S )
Longitude 102.07992 W ( 102° 4.8' W )
Positional Uncertainty 0.05 to 0.1 n.miles
Minimum Sensor or Sampling Depth 647.63 m
Maximum Sensor or Sampling Depth 647.63 m
Minimum Sensor or Sampling Height 322.37 m
Maximum Sensor or Sampling Height 322.37 m
Sea Floor Depth 970.0 m
Sea Floor Depth Source CRREP
Sensor or Sampling Distribution Fixed common depth - All sensors are grouped effectively at the same depth which is effectively fixed for the duration of the series
Sensor or Sampling Depth Datum Instantaneous - Depth measured below water line or instantaneous water body surface
Sea Floor Depth Datum Instantaneous - Depth measured below water line or instantaneous water body surface
 

Parameters

BODC CODERankUnitsTitle
AADYAA011DaysDate (time from 00:00 01/01/1760 to 00:00 UT on day)
AAFDZZ011DaysTime (time between 00:00 UT and timestamp)
ACYCAA011DimensionlessSequence number
CNDCPR011Siemens per metreElectrical conductivity of the water body by in-situ conductivity cell
PRESPS011DecibarsPressure (measured variable) exerted by the water body by fixed in-situ pressure sensor and corrected to read zero at sea level
PSALPR011DimensionlessPractical salinity of the water body by conductivity cell and computation using UNESCO 1983 algorithm
TEMPPR011Degrees CelsiusTemperature of the water body

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 - iSTAR Moorings

It is clear from data from pressure sensors (and other sensors measuring the orientation of instruments on the mooring) that the iSTAR moorings were occasionally displaced in the water column. Given the location of the mooring it is likely that this disruption was caused by ice bergs knocking in to the mooring array. This was particularly noticeable in the data from moorings iSTAR6 (where the array became ~ 60m deeper on 05 January 2013), iSTAR9 (where the array became ~ 10 m deeper between 14 and 17 November 2013) and PIG_S (where the array became ~ 50 m deeper on the 20 July 2014 and then ~50 m deeper again on 30 July 2015).


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

Sea-Bird SBE 37-SM MicroCAT

The SBE 37-SM MicroCAT is a high accuracy conductivity and temperature recorder (pressure optional). Designed for moorings and other long-duration, fixed-site deployments, MicroCATs have non-corroding titanium housings rated for operation to 7000 metres or pressure sensor full scale-range. Communication with the MicroCAT is over an internal, 3-wire, RS-232C link. The MicroCAT's aged and pressure-protected thermistor has a long history of exceptional accuracy and stability (typical drift is less than 0.002° per year). Electrical isolation of the conductivity electronics eliminates any possibility of ground-loop noise.

Specifications

  Temperature
(°C)
Conductivity (S m-1) Optional Pressure
Measurement Range -5 to +35 0 to 7 (0 to 70 mS cm-1) 0 to full scale range: 20 / 100 / 350 / 1000 / 2000 / 3500 / 7000 metres
Initial accuracy 0.002 0.0003 0.1% of full scale range
Typical Stability 0.0002 per month 0.0003 per month 0.05% of full scale range per year
Resolution 0.0001 0.00001 0.002% of full scale range
Sensor Calibration +1 to +32 0 to 6; physical calibration over range 2.6 to 6 S m-1, plus zero conductivity (air) Ambient pressure to full scale range in 5 steps
Memory 8 Mbyte non-volatile FLASH memory
Data Storage Converted temperature and conductivity: 6 bytes per sample (3 bytes each)
Time: 4 bytes per sample
Pressure (optional): 5 bytes per sample
Real-Time Clock 32,768 Hz TCXO accurate to ±1 minutes year-1
Standard Internal Batteries Nominal 10.6 Ampere-hour pack consisting of 12 AA lithium batteries. Provides sufficient capacity for more than 630,000 samples for a typical sampling scheme
Housing Titanium pressure case rated at 7000 metres
Weight (without pressure) In water: 2.3 kg
In air: 3.8 kg

Further information can be found via the following link: SBE 37-SM MicroCAT Datasheet

BODC Processing - iSTAR Moored Microcats

Data were received by BODC in Matlab files, with one file containing all data from an iSTAR mooring array. The data were reformatted to QXF (a NetCDF file format) by in house software. A separate QXF file was created for data from each instrument. Metadata were also extracted from the originator's file and used to populate the BODC database.

The following tables shows how the variables within the files were mapped to appropriate BODC parameter codes:

Originator's parameter name Originator's units Description BODC Parameter Code BODC Units Comments
temp Degrees Celsius Temperature of the water body TEMPPR01 Degrees Celsius  
cond mS/cm Electrical conductivity of the water body CNDCPR01 S/m A unit conversion of /10 has been applied to the data
press dbar Pressure exerted by the water body by fixed in situ pressure sensor and corrected to read zero at sea level PRESPS01 dbar  
salin dimensionless Practical salinity of the water body by conductivity cell and computation using UNESCO 1983 algorithm PSALPR01 dimensionless  
    Sigma-theta of the water body by CTD and computation from salinity and potential temperature using UNESCO algorithm SIGTPR01 kg/m3 Derived by BODC
    Potential temperature of the water body by computation using UNESCO 1983 algorithm POTMCV01 Degrees Celsius Derived by BODC

Following transfer to QXF, the data were quality controlled using BODC's in-house visualisation software.

Originator's processing - iSTAR Moored Microcats

Temperature, Conductivity and Pressure data were collected from SeaBird SBE-37 Microcats deployed on mooring arrays.

The originator calibrated data from the moorings with data from CTD casts taken at deployment and recovery. The Mircocats were removed from the mooring upon recovery and attached to the CTD frame to enable calibration against the ship's CTD sensors. Where appropriate offsets were applied (these are documented in the table below). In addition the conductivity and salinity data have had outliers (spikes) and few longer periods of bad data removed (set to NaN) prior to the data being supplied to BODC. It is presumed by the originator that these bad data were caused by fouling of the conductivity sensor.

2012 Deployments

Mooring Serial number Temperature offset applied
(degrees Celsius)
Conductivity offset applied
(mS/cm)
Pressure offset applied
(dbar)
Pressure scale applied
(dbar)
istar1 8530 0.0005 0.0020 0 0
istar1 8531 0.0005 0.0010 0 0
istar4 8543 0 0.0035 0 0
istar4 8544 0 0.0035 0 0
istar5 8540 0 0.0150 0 0
istar5 8541 0 0.0040 0 0
istar5 8542 0 0.0025 0 0
istar6 8538 0 0.0055 0 0
istar6 8539 0.0030 0.0027 0.5 0
istar7 8532 0 0.0060 0 0
istar7 8533 0.0013 0.0030 -0.5 0
istar8 8534 -0.0015 0.0040 0 0
istar8 8535 -0.0003 0.01200 0 0
istar9 8536 0.0006 0.01000 0 0
istar9 8537 -0.0015 0.00900 0 0

2014 Deployments

Mooring Serial number Temperature offset applied
(degrees Celsius)
Conductivity offset applied
(mS/cm)
Pressure offset applied
(dbar)
Pressure scale applied
(dbar)
pig_n 8539 0.001 0.0027 0.5 0
pig_n 8538 0 0.0055 0 0
pig_s 8532 0 0.006 0 0
pig_s 8533 0.0013 0.003 0.5 0
trough_w 8536 0.0006 0.01 0 0
trough_w 8537 -0.0015 0.009 0 0
trough_e 8543 0 0.0035 0 0
trough_e 8544 0 0.0035 0 0

Project Information

The Ice Sheet Stability (iSTAR) programme

Background and objectives

The iSTAR programme aims to measure the rate that ice is being lost from the West Antarctic ice sheet, and to improve our understanding of what might be driving this loss how it is changing over time. The rate of loss of water from ice in glaciers in the Antarctic (and Greenland) is more than the amount of water being deposited in these areas by precipitation. This has changed our understanding of these systems and the rate of ice loss is a matter of interest for sea level and climate research. Improving our understanding of the processes and impacts of changes to these systems is vital for better predictions for sea level rise in the future and will feed in to climate research. This programme combines scientific research of glaciers and the surrounding ocean environment (including how they impact each other). Research about the oceans was focused on the Amundsen Sea Sector of West Antarctica with instruments deployed from the research ship RRS James Clark Ross. Research about the ice was focused on Pine Island Glacier, Thwaites Glacier and Union Glacier with measurements taken during two expeditions across the ice. This programme was funded by the Natural Environment Research Council (NERC)

The programme is split in to four projects:

Ocean2ice: Processes and variability of ocean heat transport toward ice shelves in the Amundsen Sea Embayment (iSTAR A)

Ocean under ice: Ocean circulation and melting beneath the ice shelves of the south-eastern Amundsen Sea (iSTAR B)

Dynamic ice: Dynamical control on the response of Pine Island Glacier (iSTAR C)

Ice loss: The contribution to sea-level rise of the Amundsen Sea sector of Antarctica (iSTAR D)

Participants

The iSTAR research programme is managed by British Antarctic Survey (BAS) on behalf of NERC. Operational support, in the form of logistics planning and infrastructure, and Communication and Knowledge Exchange support are provided by BAS. There are four science projects and participants in these projects represent the following organisations:

  • British Antarctic Survey
  • National Oceanography Centre
  • Newcastle University
  • Scott Polar Research Institute
  • University College London
  • University of Bristol
  • University of East Anglia
  • University of Edinburgh
  • University of Leeds
  • University of Southampton
  • University of St. Andrews
  • University of Tasmania
  • University of Washington

Fieldwork and data collection

A wide range of data parameters were collected for this programme. Physical and chemical measurements of the ocean close to and next to the ice shelf were made using instruments deployed from ship, on moorings, on autonomous platforms and seal tags. Measurements were also made of the glaciers and ice shelfs including radar and seismic surveys and ice cores. There were also meteorological and atmospheric measurements taken. For more information about the data collected on each of the four projects see the project web pages.

Data management

Data management for ocean data will be done by the British Oceanographic Data Centre whilst ice data will be managed by the Polar Data Centre.

For more information about iSTAR programme see the: iSTAR Programme Website


Ocean2ice: Processes and variability of ocean heat transport toward ice shelves in the Amundsen Sea Embayment (iSTAR A)

Background and objectives

Ocean2ice (otherwise referred to as iSTAR A) is a project that is part of NERC's Ice Sheet Stability programme. The project was designed to investigate how relatively warm water gets close to and beneath glaciers in the Antarctic and what impact this warm water has on the rate of ice melt at these sites. This research and collection of data will to feed in to climate and sea level forecasting and research. This project was funded by the Natural Environment Research Council.

Participants

The principal investigator for the Ocean2ice project is Professor Karen Heywood, University of East Anglia. Other participants in the project represent the following organisations:

  • British Antarctic Survey
  • National Oceanography Centre
  • University of East Anglia
  • University of Southampton
  • University of St. Andrews

Fieldwork and data collection

Oceanographic data were collected from a wide range of instruments from the research ship RRS James Clark Ross between 26 January and 08 March 2014 in the Amundsen Sea. Data collected include measurements of the physical conditions (including temperature and salinity), current speeds and directions, chemical measurements of the water column (including oxygen and chlorophyll-a concentrations). A fleet of Seagliders (ocean robots that measure physical parameters including temperature, salinity and current speeds and directions) were also deployed to measure conditions close to the ice shelf. Moorings were deployed by the project and have measured conditions in the area over a couple of years. In addition Seal tags (small sensors glued to the fur of seals which fall off when the seals moult their fur) were deployed and transmit data back via satellite networks to scientists. These seal tag deployments give the scientists the rare opportunity to measure water properties below the ice shelf.

Data management

All data collected by the Ocean2ice project are to be submitted to the British Oceanographic Data Centre for careful storage, quality control, archiving and distribution to scientists, education, industry and the public.

For more information about Ocean2ice see the iSTAR A project page


Data Activity or Cruise Information

Data Activity

Start Date (yyyy-mm-dd) 2014-02-18
End Date (yyyy-mm-dd) 2016-02-03
Organization Undertaking ActivityBritish Antarctic Survey
Country of OrganizationUnited Kingdom
Originator's Data Activity IdentifierPIG_N
Platform Categorysubsurface mooring

PIG_N Mooring

PIG_N is a mooring array deployed for the iSTAR programme. The mooring was deployed from RRS James Clark Ross cruise JR20140126 in February 2014 and were recovered on RV Araon cruise ANA06B in February 2016.

Deployment date (UTC) 2014-02-18 14:00
Recovery date (UTC) 2016-02-02 23:55
Latitude (degrees, +ve North) -74.8672
Longitude (degrees, +ve East) -102.0799
Nominal water depth (m) 970

Instrument setup

Instrument Serial number Nominal depth of instrument (m) Comments
Aquatec Aqualogger 520PT Temperature/ Pressure Recorder 1308 482.4  
Aquatec Aqualogger 520T Temperature Recorder 1198 531.4  
Aquatec Aqualogger 520T Temperature Recorder 1199 581.4  
Aquatec Aqualogger 520T Temperature Recorder 1200 631.4  
Nortek Aquadopp 9391 689.0  
SeaBird SBE-37 Microcat 8539 689.5  
Aquatec Aqualogger 520T Temperature Recorder 1201 767.5  
Aquatec Aqualogger 520T Temperature Recorder 1204 848.1  
300 kHz RDI ADCP 15384 927.3  
SeaBird SBE-37 Microcat 8538 929.6  
Aquatec Aqualogger 520T Temperature Recorder 1205 956.6  

Related Data Activity activities are detailed in Appendix 1

Cruise

Cruise Name JR20140126 (JR294, JR295)
Departure Date 2014-01-26
Arrival Date 2014-03-08
Principal Scientist(s)Karen J Heywood (University of East Anglia School of Environmental Sciences)
Ship RRS James Clark Ross

Complete Cruise Metadata Report is available here


Fixed Station Information

Fixed Station Information

Station NameiSTAR8 (mid-shelf)
CategoryCoastal location
Latitude74° 51.80' S
Longitude102° 6.25' W
Water depth below MSL954.0 m

iSTAR8 (PIG_N)

Fixed station Area Latitude, degrees (positive North) Longitude, degrees (positive East)
North-West corner -74.8633 -102.1042
South-East corner -74.8672 -102.0799

Water depth = 954 m

Sampling history

Activity Latitude Longitude Deployment date Recovery date Instruments Deployment ship/ cruise Recovery ship/ cruise Comments
iSTAR8 Mooring -74.8633 -102.1042 2012-02-23 2014-02-12 one Aquatec Aqualogger (temperature and pressure)
four Aquatec Aqualoggers (temperature only)
two SeaBird SBE-37 Microcats
one Nortec Aqaudopp
one 300 kHz RDI ADCP
RV Araon RRS James Clark Ross JR20140126  
CTD Cast 59 -74.8647 -102.0837 2014-02-18 N/A SeaBird SBE 911plus CTD
C-Star transmissometer
Aquatracka Fluorometer
SeaBird SBE-43 Oxygen sensor
PAR sensor
Altimeter PA200
RRS James Clark Ross JR20140126 N/A  
CTD bottle samples -74.8647 -102.0837 2014-02-18 N/A Salinity RRS James Clark Ross JR20140126 N/A  
PIG_N mooring -74.8672 -102.0799 2014-02-18 2016-02-02 one Aquatec Aqualogger (temperature and pressure)
six Aquatec Aqualoggers (temperature only)
two SeaBird SBE-37 Microcats
one Nortec Aqaudopp
one 300 kHz RDI ADCP
RRS James Clark Ross JR20140126 RV Araon ANA06B  .

Related Fixed Station activities are detailed in Appendix 2


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

Appendix 1: PIG_N

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.

Series IdentifierData CategoryStart date/timeStart positionCruise
1748728Currents -subsurface Eulerian2014-02-18 14:20:0074.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748808Hydrography time series at depth2014-02-18 14:20:0074.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748821Hydrography time series at depth2014-02-18 14:20:0074.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748833Hydrography time series at depth2014-02-18 14:20:0074.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748845Hydrography time series at depth2014-02-18 14:20:0074.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748857Hydrography time series at depth2014-02-18 14:20:0074.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748869Hydrography time series at depth2014-02-18 14:20:0074.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748949Hydrography time series at depth2014-02-18 14:20:0074.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1763922Hydrography time series at depth2014-02-18 14:20:0174.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748624Currents -subsurface Eulerian2014-02-18 14:30:0074.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748636Currents -subsurface Eulerian2015-01-01 00:08:1274.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748648Currents -subsurface Eulerian2016-01-01 00:17:4174.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)

Appendix 2: iSTAR8 (mid-shelf)

Related series for this Fixed Station 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.

Series IdentifierData CategoryStart date/timeStart positionCruise
1748600Currents -subsurface Eulerian2012-02-22 17:00:0074.8633 S, 102.10417 WNot applicable
1717428Hydrography time series at depth2012-02-23 18:39:5374.8633 S, 102.10417 WNot applicable
1717489Currents -subsurface Eulerian2012-02-23 18:39:5974.8633 S, 102.10417 WNot applicable
1717011Hydrography time series at depth2012-02-23 18:40:0174.8633 S, 102.10417 WNot applicable
1717023Hydrography time series at depth2012-02-23 18:40:0174.8633 S, 102.10417 WNot applicable
1717324Hydrography time series at depth2012-02-23 18:44:5374.8633 S, 102.10417 WNot applicable
1717336Hydrography time series at depth2012-02-23 18:44:5774.8633 S, 102.10417 WNot applicable
1717312Hydrography time series at depth2012-02-23 18:45:0074.8633 S, 102.10417 WNot applicable
1717300Hydrography time series at depth2012-02-23 18:45:0474.8633 S, 102.10417 WNot applicable
1748612Currents -subsurface Eulerian2013-01-01 00:08:1874.8633 S, 102.10417 WNot applicable
1748728Currents -subsurface Eulerian2014-02-18 14:20:0074.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748808Hydrography time series at depth2014-02-18 14:20:0074.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748821Hydrography time series at depth2014-02-18 14:20:0074.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748833Hydrography time series at depth2014-02-18 14:20:0074.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748845Hydrography time series at depth2014-02-18 14:20:0074.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748857Hydrography time series at depth2014-02-18 14:20:0074.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748869Hydrography time series at depth2014-02-18 14:20:0074.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748949Hydrography time series at depth2014-02-18 14:20:0074.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1763922Hydrography time series at depth2014-02-18 14:20:0174.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748624Currents -subsurface Eulerian2014-02-18 14:30:0074.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748636Currents -subsurface Eulerian2015-01-01 00:08:1274.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)
1748648Currents -subsurface Eulerian2016-01-01 00:17:4174.8672 S, 102.07992 WRRS James Clark Ross JR20140126 (JR294, JR295)