Metadata Report for BODC Series Reference Number 1039361

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

Data Description

Data Category

Hydrography time series at depth

Instrument Type

Name	Categories
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

Ms Sarah Hughes

Originating Organization

Marine Scotland Aberdeen Marine Laboratory

Processing Status

banked

Online delivery of data

Download available - Ocean Data View (ODV) format

Project(s)

Data Identifiers

Originator's Identifier	772/3
BODC Series Reference	1039361

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm)	2009-05-24 15:32
End Time (yyyy-mm-dd hh:mm)	2009-10-05 07:18
Nominal Cycle Interval	120.0 seconds

Spatial Co-ordinates

Latitude	60.16650 N ( 60° 10.0' N )
Longitude	0.16667 W ( 0° 10.0' W )
Positional Uncertainty	0.05 to 0.1 n.miles
Minimum Sensor or Sampling Depth	113.0 m
Maximum Sensor or Sampling Depth	113.0 m
Minimum Sensor or Sampling Height	11.0 m
Maximum Sensor or Sampling Height	11.0 m
Sea Floor Depth	124.0 m
Sea Floor Depth Source	-
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 CODE	Rank	Units	Title
AADYAA01	1	Days	Date (time from 00:00 01/01/1760 to 00:00 UT on day)
AAFDZZ01	1	Days	Time (time between 00:00 UT and timestamp)
PREXPS01	1	Decibars	Pressure (measured variable) exerted by the water body by fixed in-situ pressure sensor and corrected to read zero at sea level
PSALPR01	1	Dimensionless	Practical salinity of the water body by conductivity cell and computation using UNESCO 1983 algorithm
TEMPPR01	1	Degrees Celsius	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 quality report

The salinity and temperature data show a significant degradation in quality towards the end of the series. No flags have been added to the data as it is impossible to identify a point at which the decline in quality begins. These data should be treated with caution.

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

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

Originator's Data Processing

Marine Scotland applied the standard manufacturers' calibrations to all current, temperature and salinity data and produced ASCII files for submission to BODC. Data files (.hmo) were named according to the mooring code and the instrument number. Each current meter file contained eastward and northward velocities and temperature. In cases where the temperature data ran for longer than the current data, the temperature records were saved as separate files appended 't'. Salinity data for each instrument were contained in files appended 's'. Header metadata were collated in additional files (.frm). Speed/Direction distributions (.csd) and harmonic analyses files (.lpr) for the current meter data were also generated.

BODC Processing

Data were received in ASCII format files. The series were reformatted to QXF (a netCDF format) using the BODC transfer function 325. The following table shows how the variables within the file were mapped to the appropriate BODC parameter codes.

Original parameter name	Original Units	BODC Parameter Code	BODC Units	Comments
Time	DD/MM/YYYY HH:MI (GMT)	AADYAA01, AAFDZZ01	day number, day fraction	Conversion by transfer
Pressure	decibars	PREXPS01	decibars
Temperature	°C	TEMPPR01	°C
Salinity	p.p.t.	PSALPR01	Dimensionless

Following transfer to QXF, the data were screened using BODC's in-house visualisation software, EDSERPLO. Any data considered as suspect were flagged accordingly. Flags from the originator marking suspect data were retained during transfer.

Project Information

No Project Information held for the Series

Data Activity or Cruise Information

Data Activity

Start Date (yyyy-mm-dd)	2009-05-24
End Date (yyyy-mm-dd)	2009-10-05
Organization Undertaking Activity	Marine Scotland Aberdeen Marine Laboratory
Country of Organization	United Kingdom
Originator's Data Activity Identifier	772
Platform Category	subsurface mooring

FRS current meter mooring (772) from East Shetland 2

A current meter mooring was deployed by Marine Scotland, Aberdeen Marine Laboratory at East Shetland 2 (60° 09.99'N, 00° 10.00'W) on 24/05/2009 during the FRV Scotia cruise 0709S. The mooring was recovered on 05/10/2009 by the FRV Scotia cruise 1309S. The station had a nominal water depth of 124m.

The mooring consisted of the following instruments

Instrument type	Series Number	Serial Number	Deployment start	Deployment end	Instrument depth (m)	No. Readings/Hour	Comments
Aanderaa Seaguard CM	7721	73	24/05/2009	05/10/2009	42	6	-
Sea-Bird SBE37-SM	7723	1684	24/05/2009	05/10/2009	113	30	-
Aanderaa Seaguard CM	7722	71	24/05/2009	05/10/2009	115	6	Degradation of salinity data due to fouling.

Related Data Activity activities are detailed in Appendix 1

Cruise

Cruise Name	0709S
Departure Date	2009-05-15
Arrival Date	2009-06-02
Principal Scientist(s)	George Slesser (Marine Scotland Aberdeen Marine Laboratory)
Ship	FRV Scotia

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