Metadata Report for BODC Series Reference Number 2073746

• 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

Thermo Scientific DELTA V Mass Spectrometer

The Thermo Scientific DELTA V series of isotope ratio mass spectrometers includes the DELTA V Advantage and the DELTA V Plus models. The two models are built on the same platform and offer all standard applications, including H₂ analysis under helium carrier gas load. The DELTA V Advantage can be upgraded to the DELTA V Plus which has additional functionality for a wider scope of applications. Features of the DELTA V generation include use with up to ten detectors, use with a wide range of sample preparation devices, Dual Inlet system, a wide range of collector configurations and integrated signal amplifiers and digitizers. In addition, the DELTA V design includes a weld-free monolithic analyzer with fixed alignment of all ion optical components, including the electro magnet.

The ion source is computer controlled, supporting manual and automatic tuning and the Dual Inlet system enables close comparison of clean sample and reference gases under viscous flow conditions. The magnet is precision-mounted into the monolithic analyser with intrinsic alignment, its pole faces determining the free flight space for the ions, thus eliminating the traditional flight tube. The gain in ion beam height directly translates into increased sensitivity. The magnet is designed for fast mass switching which is further supported by a fast jump control between consecutive measurements of multiple gases within one run. The sample gas is introduced at ground potential, eliminating the need for insulation of the flow path, ensuring 100 % transfer into the ion source. Three or more isotope ratios can be in a single sample injection. The amplifiers register ion beams up to 50 V; the dynamic range can be further extended by switching between two feedback resistors. The DELTA V series of mass spectrometers are controlled by an automated, integrated Isodat software suite.

Analytical solutions for gas chromatography, HPLC and elemental analyzers enable fully automated isotope ratio analysis on the DETLA V. The Thermo Scientific ConFlo IV Universal Interface is the most widely used interface for coupling elemental analyzers with isotope ratio mass spectrometers. The Thermo Scientific LC IsoLink is commonly used for HPLC separations and the Thermo Scientific GC IsoLink is used for compound specific isotope analysis of complex mixtures separated on a capillary GC column. The DELTA V can be used with the Thermo Scientific GasBench II, a flexible continuous flow preparation device and inlet system with Repetitive Loop Injection of gases. The Thermo Scientific PreCon trace gas pre-concentrator can be connected to the GC IsoLink or the GasBench II for atmospheric trace-gas research in the ppm and ppb range.

The universal triple collector is standard on the Thermo Scientific DELTA V platform and is suitable for all standard applications involving N2, CO, NO, O2, CO2, N2O and SO2. Additional collectors include the D/H collector and individual collector arrangements.

Further details can be found in the manufacturer's manual.

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.

Nitrate isotope measurements from CTD water samples for Cruise JR17005

Originator's Protocol for Data Acquisition and Analysis

Nitrate isotope samples were collected and filtered inline from the CTD using an Acropak and were frozen at -20°C until analysis.

The isotopic composition of nitrate+nitrite (d15N-NO₃ and d18O-NO₃) was determined by the denitrifier method (Sigman et al., 2001; Casciotti et al., 2002) and following GEOTRACES protocols (Cutter et al., 2017). Measurements were made on a Delta V Advantage coupled with a Gas bench II. Samples were corrected using international reference standards N3 and USGS-34 (Weigand et al., 2016) and expressed in delta notation (d15N-NO₃ (per mil vs AIR) = (Rsam/Rstd -1) x 1000, d18O-NO₃ (per mil vs VSMOW) = (Rsam/Rstd-1) x 1000). Standards were run in triplicate with a reproducibility (d15N ±0.1per mil and d18O ±0.3per mil. Internal standards were analysed in each run and corrected using N3 and USGS-34, with an inter-run standard deviation of d15N ±0.1 per mil and d18O ±0.3per mil. Where nitrite was >2.5% of nitrate+nitrite, samples were run with sulphamic acid removal. For samples where nitrite was <2.5% of nitrate+nitrite, d15N-NO₃+NO₂ samples were corrected assuming a d15N-NO₂ of -24per mil (Kemeny et al., 2016). d18O-NO₃ data were corrected following Kemeny et al., (2016).

References Cited

Casciotti, K. L., Sigman, D. M., Hastings, M. G., Bohlke, J. K., and Hilkert, A., 2002 Measurement of the oxygen isotopic composition of nitrate in seawater and freshwater using the denitrifier method, Anal. Chem., 74, 4905-4912, 65 https://doi.org/10.1021/ac020113w

Cutter, G., Casciotti, K., Croot, P., Geibert, W., Heimburger, L.-E., Lohan, M., Plan-quette, H., Van De Flierdt, T., 2017. Sampling and the sample-handling protocoles for GEOTRACES cruises. http://www.geotraces.org/science/intercalibration/222-sampling-and-sample-handling-protocols-for-geotraces-cruises.

Kemeny, P. C., Weigand, M. A., Zhang, R., Carter, B. R., Karsh, K. L., Fawcett, S. E., and Sigman, D. M. 2016 Enzyme-level interconversion of nitrate and nitrite in the fall mixed layer ofthe Antarctic Ocean, Global Biogeochem. Cy., 30, 1069-1085, https://doi.org/10.1002/2015gb005350

Sigman, D. M., Casciotti, K. L., Andreani, M., Barford, C.,45 Galanter, M., and Bohlke, J. K., 2001 A bacterial method for the nitrogen isotopic analysis of nitrate in seawater and freshwater, Anal. Chem., 73, 4145-4153, https://doi.org/10.1021/ac010088e

Weigand, M. A., Foriel, J., Barnett, B., Oleynik, S., and Sigman, D.M., 2016 : Updates to instrumentation and protocols for isotopic analysis of nitrate by the denitrifier method, Rapid Commun. Mass Spectrom., 30, 1365-1383, https://doi.org/10.1002/rcm.7570

JR17005 Cruise report

Further information can be found in the JR17005 Cruise report.

BODC Data Processing Procedures

Data received were loaded into the BODC database using established BODC data banking procedures. A parameter mapping table is provided below:

Project Information

Changing Arctic Ocean: Implications for marine biology and biogeochemistry

Changing Arctic Ocean (CAO) is a £16 million, five year (2017-2022) research programme initially funded by the Natural Environment Research Council (NERC). The aim of the CAO programme is to understand how change in the physical environment (ice and ocean) will affect the large-scale ecosystem structure and biogeochemical functioning of the Arctic Ocean, the potential major impacts and provide projections for future ecosystem services. In July 2018, additional projects were added to the programme that were jointly funded by NERC and the German Federal Ministry of Education and Research.

Background

The Arctic Ocean is responding to global climate change in ways that are not yet fully understood and in some cases, not yet identified. The impacts of change in the Arctic are global in range and international in importance. To achieve the aim, the programme has two key research challenges:

• To develop quantified understanding of the structure and functioning of Arctic ecosystems.
• To understand the sensitivity of Arctic ecosystem structure, functioning and services to multiple stressors and the development of projections of the impacts of change.

The decision to fund the CAO project was both scientific and political and is the second largest research programme funded by NERC.

The programme involves 33 organisations, the majority of which are research institutions in the UK and Germany, and over 170 scientists. The programme consists of four large projects with an additional 12 research projects added in July 2018.

Further information can be found on the Changing Arctic Ocean website.

Participants

There are 33 organisations involved in the Changing Arctic Ocean project, these are:

• Alfred Wegener Institut (AWI)
• Bangor University
• British Antarctic Survey (BAS)
• Centre for Environment, Fisheries and Aquaculture Science (CEFAS)
• Durham University
• GEOMAR
• Helmholtz-Zentrum Geesthacht Centre for Materials and Coastal Research
• Lancaster University
• Marine Biological Association (MBA)
• Max Planck Institute for the Science of Human History
• National Oceanography Centre (NOC)
• Newcastle University
• Northumbria University
• Ocean Atmosphere Systems GmbH
• Plymouth Marine Laboratory (PML)
• Scottish Association for Marine Science (SAMS)
• Scottish Universities Environmental Research Centre (SUERC)
• Université Libre de Bruxelles
• University College London (UCL)
• University of Bristol
• University of East Anglia (UEA)
• University of Edinburgh
• University of Glasgow
• University of Huddersfield
• University of Leeds
• University of Liverpool
• University of Manchester
• University of Oldenburg
• University of Oxford
• University of Southampton
• University of St Andrews
• University of Stirling
• University of Strathclyde

In addition to the core organisation, there are a number of international collaborators.

Research Details

The four large projects funded by NERC are:

• Arctic Productivity in the seasonal Ice Zone (Arctic PRIZE)
• Can we detect changes in Arctic ecosystems? (ARISE)
• The Changing Arctic Ocean Seafloor (ChAOS) - How changing sea ice conditions impact biological communities, biogeochemical processes and ecosystems
• Mechanistic understanding of the role of diatoms in the success of the Arctic Calanus complex and implications for a warmer Arctic (DIAPOD)

The additional 12 projects added in July 2018 funded jointly by NERC and the German Federal Ministry of Education and Research are:

• Advective Pathways of nutrients and key Ecological substances in the Arctic (APEAR)
• How will changing freshwater export and terrestrial permafrost thaw influence the Arctic Ocean? (CACOON)
• Chronobiology of changing Arctic Sea Ecosystems (CHASE)
• Potential benefits and risks of borealisation for fish stocks and ecosystems in a changing Arctic Ocean (Coldfish)
• Diatom Autecological Responses with Changes To Ice Cover (Diatom-ARCTIC)
• Ecosystem functions controlled by sea ice and light in a changing Arctic (Eco-Light)
• Effects of ice stressors and pollutants on the Arctic marine cryosphere (EISPAC)
• Linking Oceanography and Multi-specific, spatially-Variable Interactions of seabirds and their prey in the Arctic (LOMVIA)
• Understanding the links between pelagic microbial ecosystems and organic matter cycling in the changing Arctic (Micro-ARC)
• Microbes to Megafauna Modelling of Arctic Seas (MiMeMo)
• Primary productivity driven by escalating Arctic nutrient fluxes? (PEANUTS)
• Pathways and emissions of climate-relevant trace gases in a changing Arctic Ocean (PETRA)

Fieldwork and Data Collection

The programme consists of seven core cruises that survey areas in the Barents Sea and the Fram Strait on board the NERC research vessel RRS James Clark Ross. Measurements will include temperature, salinity, dissolved oxygen, dissolved inorganic carbon, total alkalinity, inorganic nutrients, oxygen and carbon isotopes and underway meteorological and surface ocean observations. In addition to ship based cruise datasets gliders, moorings and animal tags are part of the fieldwork. Further data are collected from model runs.

Data Activity or Cruise Information

Data Activity

BODC Sample Metadata Report for JR17005_CTD_CTD023

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: JR17005_CTD_CTD023

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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