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Metadata Report for BODC Series Reference Number 1621611

Metadata Summary

Data Description

Data Category Water sample data
Instrument Type
unknown  unknown
Instrument Mounting lowered unmanned submersible
Originating Country United Kingdom
Originator Mr Malcolm Woodward
Originating Organization Plymouth Marine Laboratory
Processing Status banked
Online delivery of data Download available - Ocean Data View (ODV) format
Project(s) GEOTRACES

Data Identifiers

Originator's Identifier D357_CTD_NUTS_62:CTD044_S
BODC Series Reference 1621611

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 2010-11-19 09:37
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval -

Spatial Co-ordinates

Latitude 34.71109 S ( 34° 42.7' S )
Longitude 17.03716 E ( 17° 2.2' E )
Positional Uncertainty Unspecified
Minimum Sensor or Sampling Depth 6.2 m
Maximum Sensor or Sampling Depth 500.9 m
Minimum Sensor or Sampling Height 2308.8 m
Maximum Sensor or Sampling Height 2803.5 m
Sea Floor Depth 2809.7 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
BOTTFLAG1Not applicableSampling process quality flag (BODC C22)
FIRSEQID1DimensionlessBottle firing sequence number
NTRIAATX1Micromoles per litreConcentration of nitrite {NO2- CAS 14797-65-0} per unit volume of the water body [dissolved plus reactive particulate phase] by colorimetric autoanalysis
NTRZAATX1Micromoles per litreConcentration of nitrate+nitrite {NO3+NO2} per unit volume of the water body [dissolved plus reactive particulate phase] by colorimetric autoanalysis
PHOSAATX1Micromoles per litreConcentration of phosphate {PO43- CAS 14265-44-2} per unit volume of the water body [dissolved plus reactive particulate phase] by colorimetric autoanalysis
ROSPOSID1DimensionlessBottle rosette position identifier
SAMPRFNM1DimensionlessSample reference number
SLCAAATX1Micromoles per litreConcentration of silicate {SiO44- CAS 17181-37-2} per unit volume of the water body [dissolved plus reactive particulate phase] by colorimetric autoanalysis

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 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

RRS Discovery Cruise D357 (UK GEOTRACES) dissolved Nutrient CTD bottle data

Responsible investigator

Malcolm Woodward
Plymouth Marine Laboratory (PML)
Prospect Place
The Hoe
United Kingdom

Data contributor


Laboratory of analysis

Shipboard - Plymouth Marine Laboratory (PML)


To investigate the spatial and temporal variations of the micromolar nutrient species; Nitrate, Nitrite, Silicate, Ammonium and Phosphate during the research cruise across the 40 degree south transect.

Sampling and analysis was carried out according to Go-Ship protocols wherever possible, a certified International Nutrient reference materials provided by KANSO, Japan was used during this cruise, as part of the global programme to improve nutrient analysis data quality world-wide.

Originator's Data Processing

Sampling Strategy

Water samples were taken from either a 24 x 20 litre stainless steel CTD/Rosette system (SeaBird), or an automatically fired (Sea-Ram system, (SeaBird)) CTD 24 bottle system on a trace metal free titanium rosette system. These samples were processed within the trace metal free sampling laboratory container .The CTD bottles were sub sampled into acid clean, 'aged', 60 mls HDPE (nalgene) sample bottles and analysis for the nutrient samples was in most cases complete within 2-3 hours of sampling.

Clean handling techniques were employed to avoid any contamination of the samples, particularly for the ammonium samples. Gloves used were Dura-Touch, and all people sampling prior to the nutrients from the CTD wore these gloves. Samples were not decanted and kept tightly closed until just before analysis for the ammonium, this to avoid any contamination from external sources.

Sample preparation

No filtering or any storage. In the rare cases where there was an instrument delays or problems samples were stored in the dark at 5 degrees. Samples were always run at lab temperature.

Sample Analysis

All samples were analysed on a 5 channel (nitrate, nitrite, phosphate, silicate and ammonium) Bran and Luebbe AAIII segmented flow, colorimetric, autoanalyser.

The ammonium channel was dropped once the ship left the waters of the continental shelf as the sensitivity of the colorimetric system was insufficient for the water column concentrations found.

The instrument was calibrated with home produced nutrient standards and then compared against Certified Nutrient Reference Materials, from KANSO Technos, Japan. A deep water reference sample was taken from about 1000m at the first station and was used to act as a daily tracking standard.

The analytical chemical methodologies used were according to Brewer and Riley (1965) for nitrate, Grasshoff (1976) for nitrite, Kirkwood (1989) for phosphate and silicate, and Mantoura and Woodward (1983) for ammonium.

References Cited

Jia-Zhong Zhang and Jie Chi, 2002.Automated Analysis of Nanomolar Concentrations of Phosphate in Natural Waters with Liquid Waveguide. Environ. Sci. Technol., 36 (5), pp 1048-1053

Brewer P.G. and Riley J.P., 1965. The automatic determination of nitrate in seawater. Deep Sea Research, 12, 765-72.

Grasshoff K., 1976. Methods of seawater analysis. Verlag Chemie, Weinheim and New York, 317pp.

Kirkwood D., 1989. Simultaneous determination of selected nutrients in seawater. ICES CM 1989/C:29.

Mantoura R.F.C. and Woodward, E.M.S., 1983. Optimisation of indophenol blue method for the automated determination of ammonia in estuarine waters. Estuarine Coastal and Shelf Science, 17, 219-24.

BODC data processing

The data were supplied to BODC as an Excel spreadsheet. The variables supplied by the Data Originator were mapped to BODC parameter vocabularies as follows:

Originator's Parameter Units Description BODC Parameter Code Units Comments
Nitrate+nitrite µmol l-1 Concentration of nitrate+nitrite {NO3+NO2} per unit volume of the water body [dissolved plus reactive particulate phase] by colorimetric autoanalysis NTRZAATX µmol l-1 n/a
Nitrite µmol l-1 Concentration of nitrite {NO2} per unit volume of the water body [dissolved plus reactive particulate phase] by colorimetric autoanalysis NTRIAATX µmol l-1 n/a
Phosphate µmol l-1 Concentration of phosphate {PO4} per unit volume of the water body [dissolved plus reactive particulate phase] by colorimetric autoanalysis PHOSAATX µmol l-1 n/a
Silicate µmol l-1 Concentration of silicate {SiO4} per unit volume of the water body [dissolved plus reactive particulate phase] by colorimetric autoanalysis SLCAAATX µmol l-1 n/a
Ammonium µmol l-1 Concentration of ammonium {NH4} per unit volume of the water body [dissolved plus reactive particulate phase] by colorimetric autoanalysis AMONAATX µmol l-1 n/a

Data Quality

Numerous data had been flagged at being below the limit of detection by the originator. These data have been assigned the BODC flag '<'.

CTD009_S bottle 13,14,15,16,17, CTD019_S bottle 6, CTD042_S bottle 14 and CTD046_S bottle 5 have been marked as suspect by the data originator. All data from these bottles have been assigned BODC flag 'L'.

Problem report


Project Information



GEOTRACES is an international programme sponsored by SCOR which aims to improve our understanding of biogeochemical cycles and large-scale distribution of trace elements and their isotopes (TEIs) in the marine environment. The global field programme started in 2009 and will run for at least a decade. Before the official launch of GEOTRACES, fieldwork was carried out as part of the International Polar Year (IPY)(2007-2009) where 14 cruises were connected to GEOTRACES.

GEOTRACES is expected to become the largest programme to focus on the chemistry of the oceans and will improve our understanding of past, present and future distributions of TEIs and their relationships to important global processes.

This initiative was prompted by the increasing recognition that TEIs are playing a crucial role as regulators and recorders of important biogeochemical and physical processes that control the structure and productivity of marine ecosystems, the dispersion of contaminants in the marine environment, the level of greenhouse gases in the atmosphere, and global climate.

Scientific Objectives

GEOTRACES mission is: To identify processes and quantify fluxes that control the distribution of key trace elements and isotopes in the ocean, and to establish the sensitivity of these distributions to changing environmental conditions.

Three overriding goals support the GEOTRACES mission

  • Determine ocean distributions of selected TEIs at all major ocean basins
  • Evaluate the sources, sinks, and internal cycling of these TEIs and thereby characterize more completely their global biogeochemical cycles
  • Provide a baseline distribution in the Polar Regions as reference for assessing past and future changes.

These goals will be pursued through complementary research strategies, including observations, experiments and modelling.


The central component of GEOTRACES fieldwork will be a series of cruises spanning all Ocean basins see map below.

BODC image

Three types of cruise are required to meet the goals set out by GEOTRACES. These are

  • Section cruises - These will measure all the key parameters (see below) over the full depth of the water column. The sections were discussed and approved by the International GEOTRACES Scientific Steering Committee at the basin workshops.
  • Process Studies - These will investigate a particular process relevant to the cycling of trace metal and isotopes. They must follow the "Criteria for Establishing GEOTRACES Process Studies" and be approved by the International GEOTRACES Scientific Steering Committee.
  • Cruises collecting GEOTRACES compliant data - These will collect some trace element or isotope data. They must follow the GEOTRACES Intercalibration and Data Management protocols


The IPY-GEOTRACES programme comprised of 14 research cruises on ships from 7 nations; Australia, Canada, France, Germany, New Zealand, Japan and Russia. The cruises will not be classified in the same way as the full GEOTRACES programme since the intercalibration protocols and data management protocols had not been established before the start of the IPY. But IPY-GEOTRACES data will still be quality controlled by GDAC and in the majority of cases verified versus Intercalibration standards or protocols.

Key parameters

The key parameters as set out by the GEOTRACES science plan are as follows: Fe, Al, Zn, Mn, Cd, Cu; 15N, 13C; 230Th, 231Pa; Pb isotopes, Nd isotopes; stored sample, particles, aerosols.


Data Activity or Cruise Information

Data Activity

Start Date (yyyy-mm-dd) 2010-11-19
End Date (yyyy-mm-dd) 2010-11-19
Organization Undertaking ActivityUniversity of Oxford Department of Earth Sciences
Country of OrganizationUnited Kingdom
Originator's Data Activity IdentifierD357_CTD_CTD044_S
Platform Categorylowered unmanned submersible

BODC Sample Metadata Report for D357_CTD_CTD044_S

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
237986   1 1  504.90  505.50  500.90 unknown No problem reported 860  
237987   2 2  404.10  404.80  401.10 unknown No problem reported 861  
237988   3 3  303.60  304.10  301.50 unknown No problem reported 862  
237989   4 4  263.30  263.90  261.60 unknown No problem reported 863  
237990   5 5  242.80  243.40  241.10 unknown No problem reported 864  
237991   6 6  233.00  233.30  231.30 unknown No problem reported 865  
237992   7 7  222.80  223.30  221.30 unknown No problem reported 866  
237993   8 8  212.80  213.40  211.40 unknown No problem reported 867  
237994   9 9  202.70  203.40  201.50 unknown No problem reported 868  
237995   10 10  192.70  193.10  191.50 unknown No problem reported 869  
237996   11 11  182.10  182.90  181.20 unknown No problem reported 870  
237997   12 12  171.80  172.30  170.70 unknown Bottle leak 871  
237998   13 13  162.00  162.60  161.20 unknown No problem reported 872  
237999   14 14  151.80  152.20  150.80 unknown No problem reported 873  
238000   15 15  131.60  132.10  130.80 unknown No problem reported 874  
238001   16 16  122.00  122.40  121.30 unknown No problem reported 875  
238002   17 17  101.70  101.90  101.00 unknown No problem reported 876  
238003   18 18   71.40   72.10   71.10 unknown No problem reported 877  
238004   19 19   50.70   51.30   50.60 unknown No problem reported 878  
238005   20 20   41.30   41.80   41.20 unknown No problem reported 879  
238006   21 21   36.50   36.80   36.30 unknown No problem reported 880  
238007   22 22   21.10   21.60   21.20 unknown No problem reported 881  
238008   23 23   11.00   11.50   11.20 unknown No problem reported 882  
238009   24 24    5.90    6.70    6.20 unknown No problem reported 883  

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 D357 (GA10)
Departure Date 2010-10-18
Arrival Date 2010-11-22
Principal Scientist(s)Gideon Henderson (University of Oxford Department of Earth Sciences)
Ship RRS Discovery

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