Metadata Report for BODC Series Reference Number 1985538

• 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

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

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 and Lever Action bottles have a capacity between 1.7 and 30 L. Reversing thermometers may be attached to a spring-loaded disk that rotates through 180° on bottle closure.

Dissolved iron concentrations in seawater for UK SOLAS Cruise D326

Originator's Protocol for Data Acquisition and Analysis

Samples for dissolved iron profiles were drawn from trace metal clean CTD casts. Underway samples were taken from 3 m depth, alongside the ship, using a trace metal clean fish. Sea water was filtered through a Sartobran 300 filter capsule with a 0.2 µm cut-off. Polyethylene sample bottles were washed using the protocol detailed by Achterberg et al, 2001. Samples were acidified to pH 2 (final concentration 0.011 M) using ultra clean HCL.

Dissolved iron was measured using an automated flow injection analysis and luminol based chemiluminescence detection. Dissolved Fe(II + III) was determined after reduction of all Fe(III) to Fe(II) by sulfite, and subsequent matrix elimination and preconcentration on an 8-hydroxyquinoline chelating resign column. A 0.02 M Fe(II) stock solution (prepared monthly) was used during the cruise, and other standards prepared daily by serial dilution.

For full details please see Rijkenberg et al., 2008.

References Cited

Achterberg E.A., Holland T.W., Bowie A.R., Mantoura R.F.C., Worsfold P.J., 2001. Determination of iron in seawater. Analytical Chimica Acta, 442, 1-14.

Rijkenberg M.J.A., Powell C.F., Dall'Osto M., Nielsdottir M.C., Patey M.D., Hill P.G., Baker A.R., Jickells T.D., Harrison R.M., Achterberg E.P., 2008. Changes in iron speciation following a Saharan dust event in the tropical North Atlantic Ocean. Marine Chemistry, 110, 56-67.

BODC Data Processing Procedures

Data from trace metal clean CTD casts were submitted to BODC in a spreadsheet format file (Compendium_CTDstations_D326_230109.xls) containing dissolved iron and assoicated standard deviation, other measured parameters from multiple originators, and the following metadata fields: cast number, date, julian day, CTD bottle number, time, latitude and longitude.

Data from the trace metal clean towed fish were received by BODC in a spreadsheet format file (Complexation_data_for_BODC_121009.xls) containing dissolved iron and associated standard deviation, Fe ligand data and the following metadata fields: sample I.D., julian day, date, time, latitude and longitude.

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

Data Quality Report

No data quality issues to report.

Project Information

UK Surface Ocean Lower Atmosphere Study

The UK Surface Ocean Lower Atmosphere Study (UK SOLAS) is the UK's contribution to the international SOLAS programme.

UK SOLAS formed interdisciplinary teams to address three primary aims

• To determine the mechanisms controlling rates of chemical transfer and improve estimates of chemical exchanges
• To evaluate the impact of these exchanges on the biogeochemistry of the surface ocean and lower atmosphere and on feedbacks between the ocean and atmosphere
• To quantify the impacts of these boundary layer processes on the global climate system

UK SOLAS started in 2003, to run for seven years. The programme was funded by the Natural Environment Research Council.

Funded projects

In total, 19 projects have been funded by UK SOLAS, over four funding rounds.

UK SOLAS has also supported ten tied studentships, and two CASE studentships.

Fieldwork

UK SOLAS fieldwork has included eight dedicated research cruises in the North Atlantic Ocean. Continuous measurements were made aboard aboard the Norwegian weather ship, Polarfront, until her decommission in 2009. Time series have been established at the SOLAS Cape Verde Observatory, and at the Plymouth Marine Laboratory L4 station. Experiments have taken place at the Bergen mesocosm facility.

A series of collaborative aircraft campaigns have added complementary atmospheric data. These campaigns were funded by UK SOLAS, African Monsoon Multidisciplinary Analyses (AMMA-UK), Dust and Biomass Experiment (DABEX) and the Facility for Airborne Atmospheric Measurements (FAAM).

Weblink: http://www.nerc.ac.uk/research/programmes/solas/

Data Activity or Cruise Information

Data Activity

BODC Sample Metadata Report for D326_CTD_16434B

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: D326_CTD_16434B

Related series for this Data Activity are presented in the table below. Further information can be found by following the appropriate links.

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