Metadata Report for BODC Series Reference Number 1868583

• Metadata Summary

• Problem Reports

• Data Access Policy

• Narrative Documents

• Project Information

• Data Activity or Cruise Information

• Fixed Station Information

• BODC Quality Flags

• SeaDataNet Quality Flags

Metadata Summary

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

GO-FLO Bottle

A water sampling bottle featuring close-open-close operation. The bottle opens automatically at approximately 10 metres and flushes until closed. Sampling with these bottles avoids contamination at the surface, internal spring contamination, loss of sample on deck and exchange of water from different depths.

There are several sizes available, from 1.7 to 100 litres and are made of PVC with a depth rating of up to 500 m. These bottles can be attached to a rosette or placed on a cable at selected positions.

Dissolved and Colloidal Trace Metals for cruises Belgica BG9309 and BG9322, Charles Darwin CD84 and RRS Discovery DI216

Document History

Converted from CDROM documentation.

Content of data series

Data Originator

Dr Peter Statham, Southampton Oceanography Centre, UK.

Sampling strategy and methodology

Trace metal clean procedures developed for open ocean work were used throughout the sample collection and processing. Seawater samples were filtered directly from the CTD rosette bottles (Teflon lined GoFlo on cruises BG9309, BG9322A and CD84: lever-action Niskin bottles on cruises CD94 and DI216) under about 1 bar nitrogen pressure through acid-cleaned 0.4 micron Nuclepore filters mounted in PTFE holders.

Samples were acidified by addition of 1 ml sub-boiling distilled HNO₃ per litre of seawater (except samples for Al analysis) and stored in acid-cleaned (Morley et al. 1988) low density polythene bottles.

This was undertaken using the specialised clean facilities in the Department of Oceanography, University of Southampton and (from 1994) Southampton Oceanography Centre. Dissolved metals were extracted and pre-concentrated following the dithiocarbamate complexation-freon extraction method of Danielsson et al. (1982), as modified by Statham (1985) and Tappin (1988), and were determined by graphite furnace atomic absorption spectrophotometry (GFAAS). Within batch analytical precision of the method is generally less than 10% (coefficient of variation) for each metal. More details of the method are given in Tappin et al. (1992).

Quality control (i.e. accuracy and between batch analytical precision) of the data was assessed by regularly analysing aliquots of the CASS-1 coastal seawater reference sample for dissolved trace metals and a bulk filtered acidified sea water sample which was used for batch-to-batch quality control. Results of these analyses were satisfactory, with very few exceptions, and ensure that the data are of high quality.

The method used for aluminium analysis by Peter Statham's student (Ruth Parker) on Discovery 216 is exactly as described below for David Hydes and Lei Chou.

Comments on data quality

Charles Darwin cruise CD84

In the second OMEX annual report, IBM reported that an intercalibration exercise between IBM and SOC on this cruise showed the IBM Cd concentrations to be about 20% higher, Cu determinations from both laboratories to be virtually identical and IBM Ni determinations to be lower.

A small number of very high values in both the IBM and SOC data sets that may only be explained in terms of contamination have been flagged suspect ('M') by BODC. Other values flagged 'M' which otherwise look reasonable are from bottles for which there is strong evidence of contamination of deep water samples by shallow water through leakage.

A number of data values in the ULB aluminium data set have been flagged either 'L' or 'M' in the database. The data values flagged 'L' were reported as contaminated by the originator. The values flagged 'M' are from bottles where there is strong evidence of contamination of deep water samples by shallow water through leakage.

Discovery cruise DI216

A number of data values in the ULB aluminium data set have been flagged either 'L' or 'M' in the database. The data values flagged 'L' were reported as contaminated by the originator. The values flagged 'M' are from bottles where there is strong evidence of contamination of deep water samples by shallow water through leakage.

References

Achterberg, E. P. and van den Berg, C. M. G., 1994. Automated voltammetric system for shipboard determination of metal speciation in sea water. Anal. Chim. Acta 284, 463-471.

Colombo, C and van den Berg, C. M. G., 1997. Simultaneous determination of several trace metals in seawater using cathodic stripping voltammetry with mixed ligands. Anal. Chim. Acta 337, 29-40.

Danielsson, L.G., Magnusson, B., Westerlund, S. and Zhang, K., 1982. Trace metal determination in estuarine waters by electrothermal AAS after extraction of dithiocarbamate complexes into freon. Anal. Chim. Acta, 144, 183-188.

Hydes, D.J. and P.S. Liss, 1976. A fluorometric method for the determination of low concentrations of dissolved aluminium in natural waters. The Analyst, 101, 922-931.

Mills, G.L., McFadden, E. and Quinn, J.G., 1987. Chromatographic studies of dissolved organic matter and copper-organic complexes isolated from estuarine waters. Mar. Chem., 20, 313-323.

Morley, N.H., Fay, C.W., and Statham, P.J., 1988. Design and use of a clean shipboard handling system for seawater samples. Advances in Underwater Technology, Ocean Science and Offshore Engineering, 16, Oceanology '88, 283-289.

Nimmo, M., van den Berg, C. M. G. and Brown, J., 1989. The chemical speciation of dissolved nickel, copper, vanadium and iron in Liverpool Bay, Irish Sea. Coastal Shelf Res. 29, 57-74.

Pihlar, B., Valenta, P. and Nurnberg, H. W., 1981. New high-performance analytical procedure for the voltammetric determination of nickel in routine analysis of waters, biological materials and food. Fres. Z. Anal. Chem. 307, 337-346.

Statham, P.J., 1985. The determination of dissolved manganese and cadmium in sea water at low nmol l-1 concentrations by chelation and extraction followed by electrothermal atomic absorption spectrometry. Anal. Chim. Acta, 169, 149-159.

Tappin, A.D., 1988 Trace metals in shelf seas of the British Isles, Ph.D.Thesis, University of Southampton, 279pp.

Tappin A.D., D.J. Hydes, P.J. Statham and Burton, J.D., 1992. Concentrations, distributions and seasonal variability of dissolved Cd, Co, Cu, Mn, Ni, Pb and Zn in the English Channel. Continental Shelf Research, 12,.

Project Information

No Project Information held for the Series

Data Activity or Cruise Information

Data Activity

BODC Sample Metadata Report for BG9309_CTD_GC10I

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.

Related Data Activity activities are detailed in Appendix 1

Cruise

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:

SeaDataNet Quality Control Flags

The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:

Appendix 1: BG9309_CTD_GC10I

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