Metadata Report for BODC Series Reference Number 1223176


Metadata Summary

Data Description

Data Category Hydrography time series at depth
Instrument Type
NameCategories
Sea-Bird SBE 39 temperature recorder  water temperature sensor
Instrument Mounting subsurface mooring
Originating Country United Kingdom
Originator Mr Povl Abrahamsen
Originating Organization British Antarctic Survey
Processing Status banked
Project(s) -
 

Data Identifiers

Originator's Identifier CI1_0607_3_SBE39_110_3578M
BODC Series Reference 1223176
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 2005-12-27 00:34
End Time (yyyy-mm-dd hh:mm) 2007-02-24 15:50
Nominal Cycle Interval 300.0 seconds
 

Spatial Co-ordinates

Latitude 60.27284 S ( 60° 16.4' S )
Longitude 45.26256 W ( 45° 15.8' W )
Positional Uncertainty 0.0 to 0.01 n.miles
Minimum Sensor Depth 3578.0 m
Maximum Sensor Depth 3578.0 m
Minimum Sensor Height 400.0 m
Maximum Sensor Height 400.0 m
Sea Floor Depth 3978.0 m
Sensor Distribution Fixed common depth - All sensors are grouped effectively at the same depth which is effectively fixed for the duration of the series
Sensor Depth Datum Approximate - Depth is only approximate
Sea Floor Depth Datum Instantaneous - Depth measured below water line or instantaneous water body surface
 

Parameters

BODC CODE Rank Units Short Title Title
AADYAA01 1 Days Date(Loch_Day) Date (time from 00:00 01/01/1760 to 00:00 UT on day)
AAFDZZ01 1 Days Time(Day_Fract) Time (time between 00:00 UT and timestamp)
ACYCAA01 1 Dimensionless Record_No Sequence number
TEMPPR01 1 Degrees Celsius Temp Temperature 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


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

SeaBird SBE 39 Temperature Recorder

The SBE 39 is a high-accuracy temperature recorder (pressure optional) with internal battery and non-volatile memory for deployment at depths up to 10500 meters. The SBE 39 is intended for moorings or other long-term, fixed-site applications, as well as shorter-term deployments on nets, towed vehicles or ROVs. Calibration coefficients stored in EEPROM allow the SBE 39 to transmit data in engineering units. The SBE 39's thermistor has a long history of exceptional accuracy and stability (typical drift is less than 0.002°C per year). The SBE 39 communicates directly with a computer via a standard RA-232 interface.

  Temperature (°C) Pressure (optional)
Measurement Range -5 to +35 0 to full scale range: 20 / 100 / 350 / 1000 / 2000 / 3500 / 7000 metres
Pressure expressed in metres of deployment depth capability
Initial Accuracy 0.002 0.1% of full scale range
Typical Stability (per month) 0.0002 0.004% of full scale range
Resolution 0.0001 0.002% of full scale range
Sensor Calibration -1 to + 32 Ambient pressure to full scale range in 5 steps
Memory 4M byte non-volatile FLASH memory
Data Storage Converted temperature: 3 bytes per sample
Time: 4 bytes per sample
Pressure(optional): 2 bytes per sample
Real-Time Clock Watch-crystal type 32,768 Hz; Accuracy 5 seconds/month
Internal Battery Standard: 9 volt non-hazardous lithium battery
Optional: 9-volt alkaline transistor battery
Materials Standard: Celcon plastic pressure case rated at 350 metres
Optional: Titanium pressure case rated at 10500 metres

Further information can be found via the following link Official Seabird Website .

Data Processing Notes

Data submitted to BODC were transferred using standardised procedures and originator's parameters were matched to the BODC parameter vocabulary. Unit conversions were applied when originator's units did not match the ones specified on the dictionary.

Once data were transferred, several checks were performed on the file's header and data cycles. These include:

Data were inspected visually for anomalous values, spikes, jumps, effects of mooring "knock-down" and quality flags applied where appropriate. The term 'knock-down' refers to the situation when the 'drag' exerted on a mooring at high current speeds may cause instruments to tilt beyond the angle at which they are intended to operate. At this point the efficiency of the current sensors to accurately record the flow is reduced.

Inconsistencies between the characteristics of the data set and those of its neighbours are sought, and where necessary, documented. This covers inconsistencies in the following:

Originator's Data processing

Sampling strategy

Sampling was carried out as part of the BAS LTMS (British Antarctic Survey Long Term Monitoring and Survey). The project involved the deployment of moorings CI1, CI2, OP1, OP2, OP3, OP4, OP5 and OP6 in the Southern Ocean, situated north of Coronation Island and the Orkney Passage in the Weddell and Scotia Sea.

SBE 37 and SBE39 instruments were deployed on all mooring sites from 2005 onwards. Data have been collected at variable intervals: 5 minutes interval on CI moorings, 7.5 minute interval on the instruments deployed on OP2 in 2007 and 15 minute intervals since then. Gaps in the series may be caused by either instruments not being recovered, or data not being collected due to instrument malfunction.

Data processing

Little information is known with regards to the exact details of the calibrations carried out on the mooring data. Data processing, visualisation and calibration were carried out through the use of scripts for Matlab version R2014b produced and ran by the originator.

General Data Screening carried out by BODC

BODC screen both the series header qualifying information and the parameter values in the data cycles themselves.

Header information is inspected for:

Documents are written by BODC highlighting irregularities which cannot be resolved.

Data cycles are inspected using time or depth series plots of all parameters. Currents are additionally inspected using vector scatter plots and time series plots of North and East velocity components. These presentations undergo intrinsic and extrinsic screening to detect infeasible values within the data cycles themselves and inconsistencies as seen when comparing characteristics of adjacent data sets displaced with respect to depth, position or time. Values suspected of being of non-oceanographic origin may be tagged with the BODC flag denoting suspect value; the data values will not be altered.

The following types of irregularity, each relying on visual detection in the plot, are amongst those which may be flagged as suspect:

If a large percentage of the data is affected by irregularities then a Problem Report will be written rather than flagging the individual suspect values. Problem Reports are also used to highlight irregularities seen in the graphical data presentations.

Inconsistencies between the characteristics of the data set and those of its neighbours are sought and, where necessary, documented. This covers inconsistencies such as the following:

This intrinsic and extrinsic screening of the parameter values seeks to confirm the qualifying information and the source laboratory's comments on the series. In screening and collating information, every care is taken to ensure that errors of BODC making are not introduced.


Project Information


No Project Information held for the Series

Data Activity or Cruise Information

Data Activity

Start Date (yyyy-mm-dd) 2005-12-27
End Date (yyyy-mm-dd) 2007-02-24
Organization Undertaking ActivityBritish Antarctic Survey
Country of OrganizationUnited Kingdom
Originator's Data Activity IdentifierCI
Platform Categorysubsurface mooring

Coronation Island mooring 1

The mooring was deployed at the following positions:

Organisation Undertaking Activity British Antarctic Survey, Cambridge
Country of Organisation United Kingdom
Originator's Data Activity Identifier CI1
Platform Category Subsurface mooring
Latitude (+ve N) -60.2728
Longitude (+ve E) -45.2626
Water Depth (m) 3912

The mooring was deployed off Coronation Island on cruise JR20051226 (JR151) on 27 December 2005 and recovery was done on cruise ES20070116 (ES031, ES038, ES048) on 24 February 2007.

The table below lists the instruments deployed on this mooring:

Instrument type Serial Number Data start (UT) Data end (UT) Instrument depth (m)
Aanderaa RCM8 12677 2005-12-27 02:00:00 2007-02-24 14:46:00 3378
Sea Bird SBE39 110 2005-12-27 00:34:59 2007-02-24 15:49:59 3578
Aanderaa RCM11 532 2005-12-27 01:00:00 2007-02-24 14:57:00 3778
Aanderaa RCM11 517 2005-12-27 00:59:00 2007-02-24 14:49:00 3928

Data issues found at recovery

Aanderaa conductivity sensors also exhibited large jumps in two records and a rapid initial drift which the originator estimates is due to distortion/creeping to accomodate the water pressure.

Other Series linked to this Data Activity - 1368805 1618129 1618130

Cruise

Cruise Name JR20051226 (JR151)
Departure Date 2005-12-26
Arrival Date 2005-12-27
Principal Scientist(s)Povl Abrahamsen (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