Metadata Report for BODC Series Reference Number 1350765


Metadata Summary

Data Description

Data Category Water sample data
Instrument Type
NameCategories
Niskin bottle  discrete water samplers
Instrument Mounting lowered unmanned submersible
Originating Country United Kingdom
Originator Mr Mark Stinchcombe
Originating Organization National Oceanography Centre, Southampton
Processing Status banked
Project(s) -
 

Data Identifiers

Originator's Identifier CE0716_CTD_NUTS_257:CTD07
BODC Series Reference 1350765
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 2007-06-22 12:43
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval -
 

Spatial Co-ordinates

Latitude 49.00200 N ( 49° 0.1' N )
Longitude 16.45400 W ( 16° 27.2' W )
Positional Uncertainty Unspecified
Minimum Sensor Depth 6.3 m
Maximum Sensor Depth 38.0 m
Minimum Sensor Height 4802.0 m
Maximum Sensor Height 4833.7 m
Sea Floor Depth 4840.0 m
Sensor Distribution Unspecified -
Sensor Depth Datum Unspecified -
Sea Floor Depth Datum Instantaneous - Depth measured below water line or instantaneous water body surface
 

Parameters

BODC CODE Rank Units Short Title Title
ADEPZZ01 1 Metres DepBelowSurf Depth below surface of the water body
BOTTFLAG 1 Dimensionless C22_flag Sampling process quality flag (BODC C22)
NTRZAATX 1 Micromoles per litre NO3+NO2_Unfilt_ColAA Concentration of nitrate+nitrite {NO3+NO2} per unit volume of the water body [dissolved plus reactive particulate phase] by colorimetric autoanalysis
PHOSAATX 1 Micromoles per litre PO4_Unfilt_ColAA Concentration of phosphate {PO43- CAS 14265-44-2} per unit volume of the water body [dissolved plus reactive particulate phase] by colorimetric autoanalysis
ROSPOSID 1 Dimensionless RosPos Bottle rosette position identifier
SAMPRFNM 1 Dimensionless SampRef Sample reference number
SLCAAATX 1 Micromoles per litre SiOx_Unfilt_ColAA Concentration of silicate {SiO44- CAS 17181-37-2} per unit volume of the water body [dissolved plus reactive particulate phase] by colorimetric autoanalysis
 

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

Niskin Bottle

The Niskin bottle is a device used by oceanographers to collect subsurface seawater samples. It is a plastic bottle with caps and rubber seals at each end and is deployed with the caps held open, allowing free-flushing of the bottle as it moves through the water column.

Standard Niskin

The standard version of the bottle includes a plastic-coated metal spring or elastic cord running through the interior of the bottle that joins the two caps, and the caps are held open against the spring by plastic lanyards. When the bottle reaches the desired depth the lanyards are released by a pressure-actuated switch, command signal or messenger weight and the caps are forced shut and sealed, trapping the seawater sample.

Lever Action Niskin

The Lever Action Niskin Bottle differs from the standard version, in that the caps are held open during deployment by externally mounted stainless steel springs rather than an internal spring or cord. Lever Action Niskins are recommended for applications where a completely clear sample chamber is critical or for use in deep cold water.

Clean Sampling

A modified version of the standard Niskin bottle has been developed for clean sampling. This is teflon-coated and uses a latex cord to close the caps rather than a metal spring. The clean version of the Levered Action Niskin bottle is also teflon-coated and uses epoxy covered springs in place of the stainless steel springs. These bottles are specifically designed to minimise metal contamination when sampling trace metals.

Deployment

Bottles may be deployed singly clamped to a wire or in groups of up to 48 on a rosette. Standard bottles have a capacity between 1.7 and 30 L, while Lever Action bottles have a capacity between 1.7 and 12 L. Reversing thermometers may be attached to a spring-loaded disk that rotates through 180° on bottle closure.

CTD Bottle Nutrient Samples from Celtic Explorer Cruise CE0716

Data Acquisition and Analysis

Inorganic nutrients were sampled by the CTD rosette, mainly to allow the ISUS to be calibrated. A sterilin pot was rinsed three times and then filled two thirds with water. This was then frozen for transport back to NOCS.

The nutrients were analysed at NOCS using a Skalar SanPlus Autoanalyser for nitrate, nitrite, phosphate and silicate, using the methodology of Kirkwood (1996). The following calibrations were applied:

Further information about the sampling and processing of chlorophyll samples can be found in the cruise report

References Cited

Kirkwood, D. S., 1996. Nutrients: Practical notes on their determination in seawater. In: ICES Techniques in Marine Environmental Sciences Report 17, International Council for the Exploration of the Seas, Copenhagen (1996), p.25.

BODC Data Processing Procedures

The data arrived at BODC in an excel spreadsheet. This was then saved as a comma separated values ( .csv ) format file, containing calibrated nutrient data collected during the cruise.

Originator's Parameter Unit Description BODC Parameter Code BODC Unit Comments
Nitrate μM/l Concentration of nitrate+nitrite {NO3+NO2} per unit volume of the water body [unknown phase] by colorimetric autoanalysis NTRZAATX μM/l n/a
Silicate μM/l Concentration of silicate {SiO4} per unit volume of the water body [unknown phase] by colorimetric autoanalysis SLCAAATX μM/l n/a
Phosphate μM/l Concentration of phosphate {PO4} per unit volume of the water body [unknown phase] by colorimetric autoanalysis PHOSAATX μM/l n/a

The data values were plotted and checked for consistency, and as a result none were flagged.

Data Quality Issues

Data for CTD4, Rosette position 3, flagged, as the table in the cruise report does not show a sample being taken in that location.


Project Information


No Project Information held for the Series

Data Activity or Cruise Information

Data Activity

Start Date (yyyy-mm-dd) 2007-06-22
End Date (yyyy-mm-dd) 2007-06-22
Organization Undertaking ActivityNational Oceanography Centre, Southampton
Country of OrganizationUnited Kingdom
Originator's Data Activity IdentifierCE0716_CTD_CTD07
Platform Categorylowered unmanned submersible

BODC Sample Metadata Report for CE0716_CTD_CTD07

Sample reference number Nominal collection volume(l) Bottle rosette position Bottle firing sequence number Minimum pressure sampled (dbar) Maximum pressure sampled (dbar) Depth of sampling point (m) Bottle type Sample quality flag Bottle reference Comments
209213   1     38.00   38.60   38.00 Niskin bottle No problem reported    
209214   2     31.60   31.90   31.50 Niskin bottle No problem reported    
209215   4     14.40   16.60   15.40 Niskin bottle No problem reported    
209216   13     15.40   16.10   15.60 Niskin bottle No problem reported    
209217   14     15.70   16.20   15.80 Niskin bottle No problem reported    
614675   3     20.50   21.30   20.70 Niskin bottle No problem reported    
614678   5     14.50   15.70   15.00 Niskin bottle No problem reported    
614681   6     15.20   16.80   15.90 Niskin bottle No problem reported    
614684   7     15.20   16.70   15.80 Niskin bottle No problem reported    
614687   8     15.00   16.00   15.40 Niskin bottle No problem reported    
614690   9     15.50   16.20   15.70 Niskin bottle No problem reported    
614693   10     16.00   16.30   16.00 Niskin bottle No problem reported    
614696   11     15.50   16.10   15.70 Niskin bottle No problem reported    
614699   12     15.20   15.60   15.30 Niskin bottle No problem reported    
614702   15     15.60   16.30   15.80 Niskin bottle No problem reported    
614705   16     15.20   16.20   15.60 Niskin bottle No problem reported    
614708   17     11.00   12.00   11.40 Niskin bottle No problem reported    
614711   18      6.00    6.70    6.30 Niskin bottle No problem reported    

Please note:the supplied parameters may not have been sampled from all the bottle firings described in the table above. Cross-match the Sample Reference Number above against the SAMPRFNM value in the data file to identify the relevant metadata.

Cruise

Cruise Name CE0716
Departure Date 2007-06-19
Arrival Date 2007-06-25
Principal Scientist(s)Richard Stephen Lampitt (National Oceanography Centre, Southampton)
Ship Celtic Explorer

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