Metadata Report for BODC Series Reference Number 1983464

• 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.

JR15003 CTD Bottle Nutrient Samples

Originator's Protocol for Data Acquisition and Analysis

Nutrient samples were collected during cruise JR15003 between the 6^th and 9^th January 2016. Samples were obtained at 5 stations along the repeat hydrographic section SR1b, over a range of depths. An SBE 911plus CTD unit was used, with 24 Niskin bottles fitted to the rosette sampler. Nominal 30 mL samples were drawn from the Niskin bottles into rinsed centrifuge tubes, and then immediately transferred to a -20°C freezer until analysis. Upon JCRs return to the UK, the nutrient samples were shipped on dry ice via air freight for analysis at Scripps Institution of Oceanography using a Seal Analytical segmented continuous-flow AutoAnalyzer 3 (AA3). For more information please see Scripps Nutrient Analysis Methods and the cruise report.

BODC Data Processing Procedures

The nutrient data were supplied to BODC in .csv format. Data were then loaded into BODC's database using established BODC data banking procedures.

The originator's variables were mapped to appropriate BODC parameter codes as follows:

Data Quality Report

The originator indicated that the silicate values were bad, these data were therefore assigned the BODC flag 'L'. The originator also indicated that the phosphate values may be biased high.

The BODC flag '<' was applied to nitrite data that were below the detection limit.

Project Information

NOCS National Capability

The National Oceanography Centre Southampton National Capability focuses on long term science concerned with basin/decadal variability of the Ocean.

Data Activity or Cruise Information

Data Activity

BODC Sample Metadata Report for JR15003_CTD_CTD16

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

Fixed Station Information

World Ocean Circulation Experiment (WOCE) Southern Repeat Section 1B - Falkland Islands to Elephant Island

WOCE Southern Repeat Section 1B is a section across Drake Passage in the South Atlantic Ocean. The nominal end points of the section (to date) are at 52° 55.74' S, 58° 00.00' W (at the south of the Falkland Islands) and 61° 03.05' S, 54° 33.10' W (off Elephant Island at the north end of the Antarctic Peninsula).

The section was first occupied by the R/V Polarstern in 1992 (Gersonde, 1993). The first UK occupation of SR1b followed on RRS Discovery later the same year. The National Oceanography Centre, Southampton (formerly known as Southampton Oceanography Centre), in collaboration with the British Antarctic Survey, have occupied the section most years since 1993 on the RRS James Clark Ross. Additionally, there were three Spanish occupations on R/V Hespérides in February 1995, 1996 and 1998 (Garcia et al., 2002). A Drake Passage summary report for RRS James Clark Ross cruises between 1993 - 2000 has been produced.

A table of cruises which occupied SR1b is presented below with links to the relevant cruise reports (were available).

References

García, M. A., I. Bladé, A. Cruzado, Z. Velásquez, H. García, J. Puigdefàbregas and J. Sospedra, 2002: Observed variability of water properties and transports on the World Ocean Circulation Experiment SR1b section across the Antarctic Circumpolar Current. J. Geophys. Res. 107 (C10) 3162, 10.1029/2000JC000277.

Gersonde, R., 1993: The Expedition Antarktis X/5 of RV Polarstern in 1992. Berichte zur Polarforschung, 131, 167 pp.

Related Fixed Station activities are detailed in Appendix 2

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: JR15003_CTD_CTD16

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.

Appendix 2: Drake Passage - WOCE SR1b

Related series for this Fixed Station 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.