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Metadata Report for BODC Series Reference Number 1282822


Metadata Summary

Data Description

Data Category Water sample data
Instrument Type
NameCategories
Technicap NOEX bottle  discrete water samplers
Instrument Mounting lowered unmanned submersible
Originating Country United Kingdom
Originator Dr Roger Proctor
Originating Organization Proudman Oceanographic Laboratory (now National Oceanography Centre, Liverpool)
Processing Status banked
Online delivery of data Download available - Ocean Data View (ODV) format
Project(s) LOIS Shelf Edge Study (LOIS - SES)
 

Data Identifiers

Originator's Identifier CD92B_CTD_NUTS_115:CTD41
BODC Series Reference 1282822
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 1995-04-21 01:25
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval -
 

Spatial Co-ordinates

Latitude 56.45230 N ( 56° 27.1' N )
Longitude 9.06670 W ( 9° 4.0' W )
Positional Uncertainty Unspecified
Minimum Sensor or Sampling Depth 5.0 m
Maximum Sensor or Sampling Depth 350.0 m
Minimum Sensor or Sampling Height 10.0 m
Maximum Sensor or Sampling Height 355.0 m
Sea Floor Depth 360.0 m
Sea Floor Depth Source -
Sensor or Sampling Distribution Unspecified -
Sensor or Sampling Depth Datum Unspecified -
Sea Floor Depth Datum Instantaneous - Depth measured below water line or instantaneous water body surface
 

Parameters

BODC CODERankUnitsTitle
ADEPZZ011MetresDepth (spatial coordinate) relative to water surface in the water body
BOTTFLAG1Not applicableSampling process quality flag (BODC C22)
NTRZAAD11Micromoles per litreConcentration of nitrate+nitrite {NO3+NO2} per unit volume of the water body [dissolved plus reactive particulate
PHOSAAD11Micromoles per litreConcentration of phosphate {PO43- CAS 14265-44-2} per unit volume of the water body [dissolved plus reactive particulate
SAMPRFNM1DimensionlessSample reference number

Definition of BOTTFLAG

BOTTFLAGDefinition
0The sampling event occurred without any incident being reported to BODC.
1The filter in an in-situ sampling pump physically ruptured during sample resulting in an unquantifiable loss of sampled material.
2Analytical evidence (e.g. surface water salinity measured on a sample collected at depth) indicates that the water sample has been contaminated by water from depths other than the depths of sampling.
3The feedback indicator on the deck unit reported that the bottle closure command had failed. General Oceanics deck units used on NERC vessels in the 80s and 90s were renowned for reporting misfires when the bottle had been closed. This flag is also suitable for when a trigger command is mistakenly sent to a bottle that has previously been fired.
4During the sampling deployment the bottle was fired in an order other than incrementing rosette position. Indicative of the potential for errors in the assignment of bottle firing depth, especially with General Oceanics rosettes.
5Water was reported to be escaping from the bottle as the rosette was being recovered.
6The bottle seals were observed to be incorrectly seated and the bottle was only part full of water on recovery.
7Either the bottle was found to contain no sample on recovery or there was no bottle fitted to the rosette position fired (but SBE35 record may exist).
8There is reason to doubt the accuracy of the sampling depth associated with the sample.
9The bottle air vent had not been closed prior to deployment giving rise to a risk of sample contamination through leakage.

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

Technicap NOEX bottle

The Technicap NOEX water bottle was designed for oceanographic sampling. The bottle comprises a plastic tube with caps at each end and is deployed with the caps held open, then closed at the target depth. Multiple bottles can be deployed on a CTD frame rosette. Bottle capacity is variable, but normally several litres. The bottle was developed by Technicap in the 1990s but has been superseded by more recent models. There is no known source of support available for this sampler.

Nutrients for cruises Charles Darwin and RRS Challenger

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 Roger Proctor, CCMS Proudman Oceanographic Laboratory, UK.

Sampling strategy and methodology

Charles Darwin cruises CD92B, CD93A and CD93B and RRS Challenger cruises CH120 and CH121B.

Samples were collected using either Niskin bottles deployed on a CTD rosette (CD93A, CD93B and CH121B) or NIO bottles deployed on a hydrographic wire in conjunction with a CTD cast (CD92B and CH120). The samples were immediately frozen at -18°C. The samples were transferred to the laboratory (CCMS Dunstaffnage Marine Laboratory) in dry ice and stored frozen until analysed.

Some 2-3 months after the cruise, the samples were thawed, filtered through a GF/F filter and analysed 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 NO3+NO2 = 0.93 DML NO3+NO2 - 0.14 (R2 = 0.80)
POL PO4 = 0.84 DML PO4 + 0.07 (R2 = 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:

  • To identify the time and space scales of ocean-shelf momentum transmission and to quantify the contributions to ocean-shelf water exchange by physical processes.

  • To estimate fluxes of water, heat and certain dissolved and suspended constituents across a section of the shelf edge with special emphasis on net carbon export from, and nutrient import to, the shelf.

  • To incorporate process understanding into models and test these models by comparison with observations and provide a basis for estimation of fluxes integrated over time and the length of the shelf.

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

Cruise

Cruise Name CD92B
Departure Date 1995-04-13
Arrival Date 1995-05-02
Principal Scientist(s)Anton Edwards (Dunstaffnage Marine Laboratory)
Ship RRS Charles Darwin

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
Q value below limit of quantification