Metadata Report for BODC Series Reference Number 1292379


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 Dr Ken Jones
Originating Organization Dunstaffnage Marine Laboratory (now Scottish Association for Marine Science)
Processing Status banked
Project(s) LOIS Shelf Edge Study (LOIS - SES)
 

Data Identifiers

Originator's Identifier CH128A_CTD_NUTS_59:CP43
BODC Series Reference 1292379
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 1996-07-18 14:13
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval -
 

Spatial Co-ordinates

Latitude 56.45747 N ( 56° 27.4' N )
Longitude 9.15317 W ( 9° 9.2' W )
Positional Uncertainty 0.05 to 0.1 n.miles
Minimum Sensor Depth 1.8 m
Maximum Sensor Depth 101.2 m
Minimum Sensor Height 558.0 m
Maximum Sensor Height 657.4 m
Sea Floor Depth 659.2 m
Sensor Distribution Unspecified -
Sensor Depth Datum Unspecified -
Sea Floor Depth Datum Unspecified -
 

Parameters

BODC CODE Rank Units Short Title Title
ADEPZZ01 1 Metres DepBelowSurf Depth below surface of the water body
AMONAATX 1 Micromoles per litre NH4_Unfilt_Col Concentration of ammonium {NH4+ CAS 14798-03-9} per unit volume of the water body [dissolved plus reactive particulate phase] by colorimetric autoanalysis
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
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.

Nutrients for Charles Darwin and RRS Challenger cruises

Document History

Converted from CDROM documentation.

Content of data series

AMONAATX Ammonium (unfiltered)
Colorometric autoanalysis (unfiltered)
Micromoles/litre
NTRZAAD1 Dissolved nitrate + nitrite
Colorometric autoanalysis (GF/F filtered)
Micromoles/litre
NTRZAATX Nitrate + nitrite (unfiltered)
Colorometric autoanalysis (unfiltered)
Micromoles/litre
PHOSAAD1 Dissolved phosphate
Colorometric autoanalysis (GF/F filtered)
Micromoles/litre
PHOSAATX Phosphate (unfiltered)
Colorometric autoanalysis (unfiltered)
Micromoles/litre
SLCAAATX Silicate (unfiltered)
Colorometric autoanalysis (unfiltered)
Micromoles/litre

Data Originator

Dr Ken Jones, CCMS Dunstaffnage Marine Laboratory, UK.

Sampling strategy and methodology

Charles Darwin cruises CD92B, CD93A and CD93B and RRS Challenger cruises CH120, CH121B, CH123B, CH124, CH125B, CH126B and CH128A.

Samples were collected using either Niskin bottles deployed on a CTD rosette (CD93A, CD93B, CH121B, CH123B, CH125B, CH126B and CH128A) or NIO bottles deployed on a hydrographic wire in conjunction with a CTD cast (CD92B, CH120 and CH124).

The samples were transferred to a refrigerator at 4°C immediately after collection and were analysed within a few hours on a Lachat autoanalyser using standard colorometric chemistry.

Comments on data quality

An intercalibration of the two nutrient data sets was carried out. Simple regression, excluding data values deemed suspect, yielded the following equations:

POL NO 3 +NO 2 = 0.93 DML NO 3 +NO 2 - 0.14 (R 2 = 0.80)
POL PO 4 = 0.84 DML PO 4 + 0.07 (R 2 = 0.78)

The POL nutrient values are systematically significantly lower than the DML data. When individual data values are inspected it can be seen that in some samples the POL values are down to a half of the DML values. This nutrient loss may be attributed to biological activity during sample storage.

The POL data were primarily collected to allow estimation of dissolved organic nitrogen and phosphorus from contemporary total nitrogen and phosphorus determinations. It is therefore recommended that the DML data be used for all considerations of ambient nutrient concentrations and that the POL data be considered as metadata for the TDN and TDP data.


Project Information

LOIS Shelf Edge Study (LOIS - SES)

Introduction

SES was a component of the NERC Land Ocean Interaction Study (LOIS) Community Research Programme that made intensive measurements from the shelf break in the region known as the Hebridean Slope from March 1995 to September 1996.

Scientific Rationale

SES was devoted to the study of interactions between the shelf seas and the open ocean. The specific objectives of the project were:

Fieldwork

The SES fieldwork was focussed on a box enclosing two sections across the shelf break at 56.4-56.5 °N and 56.6-56.7 °N. Moored instrument arrays were maintained throughout the experiment at stations with water depths ranging from 140 m to 1500 m, although there were heavy losses due to the intensive fishing activity in the area. The moorings included meteorological buoys, current meters, transmissometers, fluorometers, nutrient analysers (but these never returned any usable data), thermistor chains, colour sensors and sediment traps.

The moorings were serviced by research cruises at approximately three-monthly intervals. In addition to the mooring work this cruises undertook intensive CTD, water bottle and benthic surveys with cruise durations of up to 6 weeks (3 legs of approximately 2 weeks each).

Moored instrument activities associated with SES comprised current measurements in the North Channel in 1993 and the Tiree Passage from 1995-1996. These provided boundary conditions for SES modelling activities.

Additional data were provided through cruises undertaken by the Defence Evaluation and Research Agency (DERA) in a co-operative programme known as SESAME.


Data Activity or Cruise Information

Data Activity

Start Date (yyyy-mm-dd) 1996-07-18
End Date (yyyy-mm-dd) 1996-07-18
Organization Undertaking ActivityUniversity of Wales, Bangor School of Ocean Sciences (now Bangor University School of Ocean Sciences)
Country of OrganizationUnited Kingdom
Originator's Data Activity IdentifierCH128A_CTD_CP43
Platform Categorylowered unmanned submersible

BODC Sample Metadata Report for CH128A_CTD_CP43

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
83888   10.00      103.10  103.80  101.20 Niskin bottle No problem reported    
83889   10.00        5.40    5.80    4.30 Niskin bottle No problem reported    
83966   10.00       40.60   41.00   39.10 Niskin bottle No problem reported    
83967   10.00       25.50   25.80   24.10 Niskin bottle No problem reported    
83968   10.00       15.40   15.80   14.20 Niskin bottle No problem reported    
84260   10.00        3.00    3.30    1.80 Niskin bottle No problem reported    
84357   10.00       46.50   47.20   45.10 Niskin bottle No problem reported    
84358   10.00       35.40   36.20   34.20 Niskin bottle No problem reported    
84359   10.00       30.20   31.10   29.10 Niskin bottle No problem reported    
84360   10.00       20.50   20.80   19.20 Niskin bottle No problem reported    
84361   10.00       10.40   10.70    9.20 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.

Other Series linked to this Data Activity - 1677049

Cruise

Cruise Name CH128A
Departure Date 1996-07-10
Arrival Date 1996-07-26
Principal Scientist(s)John H Simpson (University of Wales, Bangor School of Ocean Sciences)
Ship RRS Challenger

Complete Cruise Metadata Report is available here


Fixed Station Information

Fixed Station Information

Station NameLOIS (SES) Repeat Section S
CategoryOffshore route/traverse

LOIS (SES) Repeat Section S

Section S was one of four repeat sections sampled during the Land-Ocean Interaction Study (LOIS) Shelf Edge Study (SES) project between March 1995 and September 1996.

The CTD measurements collected at repeat section S, on the Hebridean Slope, lie within a box bounded by co-ordinates 56° 16.8' N, 9° 40.2 W at the southwest corner and 56° 30.0' N, 8° 10.8' W at the northeast corner.

Cruises occupying section S

Cruise Start Date End Date
Charles Darwin 91B 22/03/1995 02/04/1995
Charles Darwin 92B 13/04/1995 02/05/1995
Charles Darwin 93A 07/05/1995 16/05/1995
Charles Darwin 93B 16/05/1995 30/05/1995
Challenger 120 18/07/1995 06/08/1995
Challenger 121A 10/08/1995 18/08/1995
Tydeman SESAME-1 10/08/1995 11/09/1995
Challenger 121B 18/08/1995 01/09/1995
Challenger 121C 01/09/1995 10/09/1995
Challenger 123A 15/11/1995 29/11/1995
Challenger 123B 01/12/1995 15/12/1995
Challenger 124 08/01/1996 27/01/1996
Challenger 125A 31/01/1996 12/02/1996
Challenger 125B 13/02/1996 03/03/1996
Challenger 126A 11/04/1996 26/04/1996
Challenger 126B 27/04/1996 12/05/1996
Challenger 128A 10/07/1996 26/07/1996
Challenger 128B 26/07/1996 08/08/1996

Other Series linked to this Fixed Station for this cruise - 860165 860208 860221 860233 860245 860325 860337 860349 860350 860362 860374 860386 860398 860405 860429 860430 860442 860454 860478 860522 860534 860546 860558 860583 860614 860687 860699 860706 860718 860755 860767 860779 860780 860792 860988 861003 861015 861039 1292042 1292066 1292146 1292158 1292171 1292183 1292195 1292202 1292214 1292299 1292306 1292318 1292343 1292355 1292367 1292380 1292392 1292411 1292423 1292435 1292447 1292681 1292693 1292700

Other Cruises linked to this Fixed Station (with the number of series) - CD91B (10) CD92B (16) CD93A (30) CD93B (69) CH120 (7) CH121A (21) CH121B (79) CH121C (9) CH123A (10) CH123B (28) CH125A (17) CH125B (40) CH126A (38) CH126B (54) CH128B (13)


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