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Metadata Report for BODC Series Reference Number 1306948

Metadata Summary

Data Description

Data Category Water sample data
Instrument Type
unknown  unknown
Instrument Mounting lowered unmanned submersible
Originating Country United Kingdom
Originator Mr Mick Whitehouse
Originating Organization British Antarctic Survey
Processing Status banked
Online delivery of data Download available - Ocean Data View (ODV) format
Project(s) -

Data Identifiers

Originator's Identifier JB10_LEG_2_CTD_NUTS_42:JB10_673
BODC Series Reference 1306948

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 1990-02-16 18:55
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval -

Spatial Co-ordinates

Latitude 53.65500 S ( 53° 39.3' S )
Longitude 38.57000 W ( 38° 34.2' W )
Positional Uncertainty Unspecified
Minimum Sensor or Sampling Depth 8.9 m
Maximum Sensor or Sampling Depth 1478.4 m
Minimum Sensor or Sampling Height 72.6 m
Maximum Sensor or Sampling Height 1542.1 m
Sea Floor Depth 1551.0 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


BODC CODERankUnitsTitle
ADEPZZ011MetresDepth (spatial coordinate) relative to water surface in the water body
AMONAAD31Micromoles per litreConcentration of ammonium {NH4+ CAS 14798-03-9} per unit volume of the water body [dissolved plus reactive particulate
BOTTFLAG1Not applicableSampling process quality flag (BODC C22)
NTRZAAD31Micromoles per litreConcentration of nitrate+nitrite {NO3+NO2} per unit volume of the water body [dissolved plus reactive particulate
PHOSAAD31Micromoles per litreConcentration of phosphate {PO43- CAS 14265-44-2} per unit volume of the water body [dissolved plus reactive particulate
SAMPRFNM1DimensionlessSample reference number
SLCAAAD31Micromoles per litreConcentration of silicate {SiO44- CAS 17181-37-2} per unit volume of the water body [dissolved plus reactive particulate

Definition of BOTTFLAG

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

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.

If the Information Provider does not provide a specific attribution statement, or if you are using Information from several Information Providers and multiple attributions are not practical in your product or application, you may consider using the following:

"Contains public sector information licensed under the Open Government Licence v1.0."

Narrative Documents

Nitrate, phosphate, silicate and ammonium seawater concentrations for BAS cruise JB10 Leg 2

Originator's data acquisition and analysis

Discrete samples from vertical profiles were collected using a CTD water bottle rosette. The samples were subsampled and passed through a glass fibre filter (Whatman GF/C, pore size 1.2 µm) by means of a syringe with an in-line luer-locking filtration unit. All analyses were conducted using a nutrient autoanalyser made up of Chemlab colorimeters and Ismatec pumps and custom built reaction manifolds.

Nitrate Determination of nitrate was conducted following the method described by Stainton (1974). Nitrate is reduced to nitrite by passing the sample stream through a transmission tube containing a copper-coated cadmium wire. Nitrite ions diazotise sulphanilamide then couple with N-1-naphthylethylenediamine dihydrochloride to form an azo-dye, the concentration of which is measured by absorbance at 550 nm.

Phosphate Phosphate concentration was determined following a method similar to that described by Tréguer and Le Corre (1975). Orthophosphate ions react with acidified ammonium molybdate in the presence of antimony to form phosphomolbdic acid. This is reduced by ascorbic acid to a 'molydenum blue' complex (Riley and Skirrow, 1975) the concentration of which is measured by absorbance at 630nm.

Silicate The concentration of silicate in seawater was determined using a method based on an industrial method by Technicon (1976). Silicate ions react with ammonium molybdate in acidic conditions producing silicomolybdic acid. This is reduced to a 'molybdenum blue' complex by ascorbic acid (Riley and Skirrow, 1975) and its concentration is measured by absorbance at 680 nm. Interference from phosphates at normal concentrations is eliminated by the introduction of oxalic acid into the sample stream prior to the addition of ascorbic acid.

Ammonium Ammonia is determined using a variant of the Berthelot reaction. Sodium dichloroisocyanurate is used as a hypochlorite donor (Krom, 1984) and catalysis is performed by potassium ferrocyanide. After reagent additions, the reaction stream is heated to 40°C and formation of 'indophenol blue' is promoted under longwave UV radiation (365 nm). Concentration is measured by absorbance at 630 nm.

See Whitehouse and Woodley, 1987 for full details of all instrumentation and analysis involved.

References cited

Krom M.D., 1984 Spectrophotometric determination of ammonia. A study of a modified Berthelot reaction using salicylate and dichloroisocyanurate. The Analyst, 105, 305-316.

Riley J.P. and Skirrow G., 1975. Chemical Oceanography, 3, (2nd Edition), London, Academic Press.

Stainton M.P., 1974. Simple, efficient reduction column for use in the automated determination of nitrate in water. Analytical Chemistry, 46, 1616.

Technicon Instruments Corporation, 1976. Silicates in water and wastewater. Technicon industrial method No 105-71.

Tréguer P. and Le Corre P., 1975. Manuel d'analyse des sels nutritifs dans l'eau de mer (Utilisation de l'AutoAnalyser II, Technicon, 2nd edition). Report laboratoire d'oceanologie chimique, Université de Bretagne Occidentale, Brest, France.

Whitehouse M.J. and Woodley V.R., 1987. Automated Seawater Nutrient Analysis. British Antarctic Survey, Cambridge.

BODC Data Processing Procedures

Data were received by BODC in spreadsheet format with the nutrient data from various BAS cruises in labeled worksheets (BAS_nutrient_data_1981-2009.xls). The following metadata fields were also included with the data: cruise ID, date, latitude, longitude, event number and pressure.

Parameter codes defined in the BODC parameter dictionary were mapped to the variables as follows:

Originator's Parameter Units Description BODC Parameter Code Units Comments
NO3 mmol m-3 colorimetric autoanalysis of nitrate + nitrite (<GF/C) NTRZAAD3 µmol L-1 No unit conversion necessary, units analogous with one another
NH4 mmol m-3 colorimetric autoanalysis of ammonium (<GF/C) AMONAAD3 µmol L-1 No unit conversion necessary, units analogous with one another
PO4 mmol m-3 colorimetric autoanalysis of phosphate (<GF/C) PHOSAAD3 µmol L-1 No unit conversion necessary, units analogous with one another
Si mmol m-3 colorimetric autoanalysis of silicate (<GF/C) SLCAAAD3 µmol L-1 No unit conversion necessary, units analogous with one another

Nutrient data were received with no associated time for the sampling event. It was therefore deemed necessary to acquire times from the CTD cast data inventory for this cruise already stored at BODC. Positional data from the nutrient data file and positional data from the CTD cast metadata were used to map the correct times to the nutrient sampling events.

The depth of the water column at each sampling event has been assigned using GMT and GEBCO data.

The data were banked according to BODC standard procedures for sample data. Data were banked as received, with no averaging or other modifications applied.

Data Quality Report

There are no data quality issues to report.

Project Information

No Project Information held for the Series

Data Activity or Cruise Information

Data Activity

Start Date (yyyy-mm-dd) 1990-02-16
End Date (yyyy-mm-dd) 1990-02-16
Organization Undertaking ActivityBritish Antarctic Survey
Country of OrganizationUnited Kingdom
Originator's Data Activity IdentifierJB10 LEG 2_CTD_JB10_673
Platform Categorylowered unmanned submersible

BODC Sample Metadata Report for JB10 LEG 2_CTD_JB10_673

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
212260          8.50    9.50    8.90 unknown No problem reported    
212261         11.50   12.50   11.90 unknown No problem reported    
212262         18.50   19.50   18.80 unknown No problem reported    
212263         28.50   29.50   28.70 unknown No problem reported    
212264         38.50   39.50   38.60 unknown No problem reported    
212265         58.50   59.50   58.50 unknown No problem reported    
212266         78.50   79.50   78.30 unknown No problem reported    
212267        100.50  101.50  100.10 unknown No problem reported    
212268        201.50  202.50  200.10 unknown No problem reported    
212269        493.50  494.50  489.00 unknown No problem reported    
212270       1000.50 1001.50  989.70 unknown No problem reported    
212271       1496.50 1497.50 1478.40 unknown 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 Name JB10 Leg 2
Departure Date 1990-01-31
Arrival Date 1990-02-22
Principal Scientist(s)Jonathan L Watkins (British Antarctic Survey), Julian Priddle (British Antarctic Survey)
Ship RRS John Biscoe

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
B nominal value
Q value below limit of quantification