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Metadata Report for BODC Series Reference Number 1272538


Metadata Summary

Data Description

Data Category Water sample data
Instrument Type
NameCategories
Niskin bottle  discrete water samplers
Instrument Mounting lowered unmanned submersible
Originating Country Belgium
Originator Dr Marc Elskens
Originating Organization Free University of Brussels Laboratory of Analytical and Environmental Chemistry
Processing Status banked
Online delivery of data Download available - Ocean Data View (ODV) format
Project(s) OMEX I
 

Data Identifiers

Originator's Identifier BG9522_CTD_NUTS_10:12C
BODC Series Reference 1272538
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 1995-09-23 05:18
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval -
 

Spatial Co-ordinates

Latitude 47.45328 N ( 47° 27.2' N )
Longitude 8.54366 W ( 8° 32.6' W )
Positional Uncertainty Unspecified
Minimum Sensor or Sampling Depth 3.0 m
Maximum Sensor or Sampling Depth 149.0 m
Minimum Sensor or Sampling Height -
Maximum Sensor or Sampling Height -
Sea Floor Depth -
Sea Floor Depth Source -
Sensor or Sampling Distribution Unspecified -
Sensor or Sampling Depth Datum Unspecified -
Sea Floor Depth Datum Unspecified -
 

Parameters

BODC CODERankUnitsTitle
ADEPZZ011MetresDepth (spatial coordinate) relative to water surface in the water body
AMONMATX1Micromoles per litreConcentration of ammonium {NH4+ CAS 14798-03-9} per unit volume of the water body [dissolved plus reactive particulate phase] by manual colorimetric analysis
BOTTFLAG1Not applicableSampling process quality flag (BODC C22)
NTRZAATX1Micromoles per litreConcentration of nitrate+nitrite {NO3+NO2} per unit volume of the water body [dissolved plus reactive particulate phase] by colorimetric autoanalysis
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

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

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 cruises Belgica BG9309, BG9322, BG9412, BG9506, BG9521 and BG9522

Document History

Converted from CDROM documentation.

Content of data series

AMONAAD2 Dissolved ammonium
Colorometric autoanalysis (0.4/0.45 µm pore filtered)
Micromoles/litre
AMONAATX Dissolved ammonium
Colorometric autoanalysis (unfiltered)
Micromoles/litre
AMONMATX Ammonium (unfiltered)
Manual colorometric analysis (unfiltered)
Micromoles/litre
NTRIAAD2 Dissolved nitrite
Colorometric autoanalysis (0.4/0.45 µm pore filtered)
Micromoles/litre
NTRIAAD5 Dissolved nitrite
Colorometric autoanalysis (0.2 µm pore filtered)
Micromoles/litre
NTRIAATX Nitrite (unfiltered)
Colorometric autoanalysis (unfiltered)
Micromoles/litre
NTRZAAD2 Dissolved nitrate + nitrite
Colorometric autoanalysis (0.4/0.45 µm pore filtered)
Micromoles/litre
NTRZAAD5 Dissolved nitrate + nitrite
Colorometric autoanalysis (0.2 µm pore filtered)
Micromoles/litre
NTRZAATX Nitrate + nitrite (unfiltered)
Colorometric autoanalysis (unfiltered)
Micromoles/litre
PHOSAAD2 Dissolved phosphate
Colorometric autoanalysis (0.4/0.45 µm pore filtered)
Micromoles/litre
PHOSAAD5 Dissolved phosphate
Colorometric autoanalysis (0.2 µm pore filtered)
Micromoles/litre
PHOSAATX Phosphate (unfiltered)
Colorometric autoanalysis (unfiltered)
Micromoles/litre
PHOSMATX Phosphate (unfiltered)
Manual colorometric analysis (unfiltered)
Micromoles/litre
SLCAAAD2 Dissolved silicate
Colorometric autoanalysis (0.4/0.45 µm pore filtered)
Micromoles/litre
SLCAAAD5 Dissolved silicate
Colorometric autoanalysis (0.2 µm pore filtered)
Micromoles/litre
SLCAAATX Silicate (unfiltered)
Colorometric autoanalysis (unfiltered)
Micromoles/litre
SLCAMATX Silicate (unfiltered)
Manual colorometric analysis (unfiltered)
Micromoles/litre
UREAMDTX Urea (unfiltered)
Manual analysis using the diacetylmonoxime method
Micromoles/litre

Data Originator

Ir Marc Elskens, VUB, Brussels, Belgium.

Sampling strategy and methodology

Water samples were taken from manually filled bottles deployed from an inflatable boat away from Belgica (ria surveys) or taken from water bottles deployed on a CTD rosette. On two cruises (BG9322 and BG9412) continuous underway measurements were also made by drawing discrete samples at frequent intervals from the continuous seawater supply.

Nutrient determinations were carried out on board ship, immediately after sampling. Nitrate plus nitrite and phosphate were determined using a Technicon AA2 autoanalyser as described by Elskens and Elskens (1989).

Ammonia was determined according to the manual method using indophenol blue described in Koroleff (1969) using a Baush and Lomb Spectronic 21 spectrophotometer.

Urea was determined using the diacetymonoxime method of Mulvena and Savidge (1992) modified to allow precise analyses when strict control of the reaction temperature is impossible as described by Goeyens et al. (submitted 1996).

Comments on data quality

Belgica cruise BG9309

The SKALAR autoanalyser phosphate data were supplied with a warning that there may be problems. On a number of stations all three laboratories provided phosphates and for a number of stations there were also manually analysed phosphates from ULB. Comparing these data it can be clearly seen that the SKALAR values are frequently way too high. Consequently, the SKALAR phosphate data set has been flagged 'L'.

For the stations where inter-comparison of NO3+NO2 data is possible, the ULB data are generally higher than the VUB data which are, in turn, generally higher than the CSIC data. None of the data have been flagged. Users are advised to retrieve all three data sets and reach their own conclusions about which data to use.

Belgica cruise BG9412

On this cruise the ULB NO3+NO2 data, with the exception of a handful of points, are significantly lower than the VUB data. Differences of 10 per cent and more are predominant throughout the overlapping data set.

The phosphate and nitrite data sets show excellent agreement.

References

Armstrong, F.A.J., Stearns, C.R. and Strickland, J.D.H., 1967. The measurement of upwelling and subsequent biological processes by means of the Technicon Autoanalyser and associated equipment. Deep Sea Res. 14, 381-389.

Eberlein, K. and Kattner, G. 1987. Automatic method for the determination of ortho-phosphate and total dissolved phosphorus in the marine environment. Fresenius Z. anal. Chem., 326, 354-357.

Elskens, I. and Elskens, M., 1989. Handleing voor de bepaling van nutrienten in zeewater met an Autoanalyser IITM systeem. Vrije Universiteit Brussel, 50pp..

Føyn, L., Magnussen, M. and Seglem, K., 1981. Automatisk analyse av naeringsalter med "on-line" databehandling. En presentasjon av oppbyggning og virkemåte av systemet i bruk på Havforskningsinstituttets båter og i laboratoriet. Fisken Hav., Ser. B., 4, 1-40.

Goeyens, L,. Kindermans, N., Yusuf, M.A. and Elskens, M. (submitted 1996). A room temperature procedure for the manual determination of urea in seawater. Submitted to Marine Chemistry.

Grasshoff, K., Ehrhardt, M. and Kremling, K. eds. 1983. Methods of seawater analysis. Verlag Chemie.

Koroleff, F., 1969. Direct determination of ammonia in natural waters as indophenol blue. Int. Counc. Explor. Sea, CM., 9, 19-22.

Mourino, C. and Fraga, F., 1985. Determinacion de nitratos en aqua de mar. Investigacion Pesquera, 49, 81-96.

Mulvena, P. and Savidge, G., 1992. A modified manual method for the determination of urea in seawater using diacetylmonoxime reagent. Estuarine, Coastal and Shelf Science, 34, 429-438.

Murphy, J. and Riley, J.P., 1962. A modified single solution method for the determination of phosphate in natural waters. Analytica Chim. Acta, 27, 31-36.

Rees, A.P., Owens, N.J.P. and Woodward, E.M.S. (1995). Phytoplankton nitrogen assimilation at low nutrient concentrations in the NW Mediterranean Sea. Water Pollution Research Report 32 in EROS 2000 ed J-M Martin and H. Barth, European Commission, 141-148.


Project Information

Ocean Margin EXchange (OMEX) I

Introduction

OMEX was a European multidisciplinary oceanographic research project that studied and quantified the exchange processes of carbon and associated elements between the continental shelf of western Europe and the open Atlantic Ocean. The project ran in two phases known as OMEX I (1993-1996) and OMEX II - II (1997-2000), with a bridging phase OMEX II - I (1996-1997). The project was supported by the European Union under the second and third phases of its MArine Science and Technology Programme (MAST) through contracts MAS2-CT93-0069 and MAS3-CT97-0076. It was led by Professor Roland Wollast from Université Libre de Bruxelles, Belgium and involved more than 100 scientists from 10 European countries.

Scientific Objectives

The aim of the Ocean Margin EXchange (OMEX) project was to gain a better understanding of the physical, chemical and biological processes occurring at the ocean margins in order to quantify fluxes of energy and matter (carbon, nutrients and other trace elements) across this boundary. The research culminated in the development of quantitative budgets for the areas studied using an approach based on both field measurements and modeling.

OMEX I (1993-1996)

The first phase of OMEX was divided into sub-projects by discipline:

  • Physics
  • Biogeochemical Cycles
  • Biological Processes
  • Benthic Processes
  • Carbon Cycling and Biogases

This emphasises the multidisciplinary nature of the research.

The project fieldwork focussed on the region of the European Margin adjacent to the Goban Spur (off the coast of Brittany) and the shelf break off Tromsø, Norway. However, there was also data collected off the Iberian Margin and to the west of Ireland. In all a total of 57 research cruises (excluding 295 Continuous Plankton Recorder tows) were involved in the collection of OMEX I data.

Data Availability

Field data collected during OMEX I have been published by BODC as a CD-ROM product, entitled:

  • OMEX I Project Data Set (two discs)

Further descriptions of this product and order forms may be found on the BODC web site.

The data are also held in BODC's databases and subsets may be obtained by request from BODC.


Data Activity or Cruise Information

Cruise

Cruise Name BG9522
Departure Date 1995-09-22
Arrival Date 1995-09-29
Principal Scientist(s)Ann Dewicke (University of Gent Department of Biology)
Ship RV Belgica

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