Metadata Report for BODC Series Reference Number 2058080

• 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

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

Seal Analytical AutoAnalyzer 3HR

The model AA3 is an upgrade from Seal Analytics AutoAnalyzer II and is specifically designed for colorimetric determination of dissolved nutrients in environmental smaples. This model fully automates repetitive and complex sample analysis and can perform solvent extractions, distillation, gas diffusion, on-line filtration and in-line UV digestion in a continuously flowing stream.

It has a modular design which can integrate a sampler, pump, chemistry test module and photometer. It also accepts Multitest Manifolds designed to extend any size analyzer to a multiple chemistry system capable of dual range of tests which, in turn, eliminate the need to change manifolds and filters when changing tests.

The AA3 uses segmented flow analysis principles to reduce inter-sample dispersion, it can analyse up to 100 samples per hour using stable LED light sources. It also contains glass coils, which allow for chemically inert and easy visual checks.

The available modules are:

• Digital colorimeter: bubble through the flow cell to increase sampling rate and true Dual beam operation with continuous real-time referencing
• High Precision Pump: multi-speed motor, electronic air injection, optional valves for auto reagent switching and a buil in leak detector
• Multitest Manifold: allows for up to 16 different analyses
• Chemistry Module: glass coils which are chemically inter and allow for clear view of the flow, gas difusion or dialysis options
• XY2/XY3: high capacity random access sampler, up to 180/270 samples in cups or tubes in 2/3 racks, separate rack for standards, optional integrated pump and auto-diluter
• Distillation Module: automatic in line distillation when required before colorimetric analysis

Further information can be found in the manufacturer's brochure.

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.

Atlantic Meridional Transect cruise DY110 (AMT29) Micro-molar Nutrients from CTD Bottles

Originator's Protocol for Data Acquisition and Analysis

A total of 55 vertical CTD profiles were carried out along the cruise track, and these were analysed for nutrients for the Atlantic Meridional Transect (AMT) Project. Water samples were taken from a 24 x 20 litre bottle stainless steel framed CTD / Rosette system (Seabird). The number of depths sampled from each CTD cast ranged from four to fifteen, capturing the entire available depth profile with a particular interest in sampling along the thermocline. Water was collected into clean (acid-washed) 60ml HDPE (Nalgene) sample bottles, which were rinsed three times with sample seawater prior to filling. The bottles were filled to around 75% volume, dried, and placed in a Ziploc bag before being stored at -20°C.

Micro-molar nutrient analysis of the samples was carried out on return to PML using a 4 channel (nitrate (Brewer & Riley, 1965), nitrite (Grasshoff, K., 1976), phosphate, and silicate (Kirkwood, D.S., 1989) SEAL Analytical AAIII segmented flow, colorimetric auto-analyser.

Established, proven analytical protocols were used and clean sampling and handling techniques were employed according to GO-SHIP protocols (Becker et al, 2020). Certified Nutrient reference materials from KANSO Ltd, Japan (Batch BU), were used during the analysis to ensure good quality control and reliable analytical results.

References Cited

Becker, S., Aoyama, M., Woodward, E.M.S., Bakker, K., Coverly, S., Mahaffey, C., and Tanhua. T. 2020. GO-SHIP Repeat Hydrography Nutrient Manual: The Precise and Accurate Determination of Dissolved Inorganic Nutrients in Seawater, Using Continuous Flow Analysis Methods, Front. Mar. Sci., 30 October 2020 | https://doi.org/10.3389/fmars.2020.581790

Brewer P. G. and Riley, J. P. 1965. The automatic determination of nitrate in seawater. Deep Sea Research, 12: 765-772

Grasshoff, K., 1976. Methods of sea-water analysis, Verlag Chemie, Weiheim: pp.317.

Kirkwood, D.S. 1989. Simultaneous determination of selected nutrients in sea-water, ICES CM 1989/C:29

BODC Data Processing Procedures

Data were received in Excel format and were archived under BODC's accession number PML200262. The data were provided with metadata including CTD number, Niskin bottle number and depth. The metadata provided were matched to the records already held in the BODC database using CTD number and Niskin Bottle number in the majority of cases. The data were loaded into the BODC database using established BODC data banking procedures. A parameter mapping table is provided below:

Data Quality Report

Some samples supplied were below the limit of detection for the parameter. In these cases, the data were supplied with a < flag and the detection limit. This information was loaded to the BODC database. The detection limits are 0.01 µM (Nitrite); 0.02 µM (Nitrate+Nitrite) and 0.02 µM (Phosphate).

Project Information

Marine LTSS: CLASS (Climate Linked Atlantic Sector Science)

Introduction

CLASS is a five year (2018 to 2023) programme, funded by the Natural Environment Research Council (NERC) and extended until March 2024.

Scientific Rationale

The ocean plays a vital role in sustaining life on planet Earth, providing us with both living resources and climate regulation. The trajectory of anthropogenically driven climate change will be substantially controlled by the ocean due to its absorption of excess heat and carbon from the atmosphere, with consequent impacts on ocean resources that remain poorly understood. In an era of rapid planetary change, expanding global population and intense resource exploitation, it is vital that there are internationally coordinated ocean observing and prediction systems so policy makers can make sound evidence-based decisions about how to manage our interaction with the ocean. CLASS will underpin the UK contribution to these systems, documenting and understanding change in the marine environment, evaluating the impact of climate change and effectiveness of conservation measures and predicting the future evolution of marine environments. Over the five-year period CLASS will enhance the cost-effectiveness of observing systems by migrating them towards cutting edge autonomous technologies and developing new sensors. Finally, CLASS will create effective engagement activities ensuring academic partners have transparent access to NERC marine science capability through graduate training partnerships and access to shipborne, lab based and autonomous facilities, and modelling capabilities.

Data Activity or Cruise Information

Data Activity

BODC Sample Metadata Report for DY110_CTD_CTD024

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: DY110_CTD_CTD024

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

If you are interested in these series, please be aware we offer a multiple file download service. Should your credentials be insufficient for automatic download, the service also offers a referral to our Enquiries Officer who may be able to negotiate access.