Metadata Report for BODC Series Reference Number 2116490

• 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

Carlo Erba NC 2500 elemental analyser

A laboratory instrument that simultaneously determines total nitrogen, total hydrogen and total carbon in a solid sample. The sample is completely and instantaneously oxidised by flash combustion, which converts all organic and inorganic substances into combustion products.The resulting combustion gases pass through a reduction furnace and are swept into the chromatographic column by the helium carrier gas. The gases are separated in the column and quantified or they can be introduced into another instrument, such as an isotope ratio mass spectrometer, for further analysis. The instrument was originally manufactured by CE instruments (formerly Carlo Erba) and has since been replaced by Thermo Scientific (part of Thermo Fisher Scientific). This model is no longer in production.

Stand Alone Pump (SAP)

A submersible battery powered water pump that sucks water through various filters leaving the materials of interest on the filter for analysis. SAPs are deployed clamped to a hydrographic wire and may be used to sample at depths of up to 6000 m. A SAP can pump thousands of litres of water over a few hours.

Particulate organic carbon and particulate nitrogen measurements from Stand Alone Pump (SAP) samples collected during UKOA cruise JC073

Originator's Protocol for Data Acquisition and Analysis

These data originate from analyses of samples collected near the seabed at Mingulay and Logachev cold-water coral reef systems.

A Stand-Alone Pumping System (SAPS) was used to obtain large volume filtered samples of the near-bottom water following the approach of Kiriakoulakis et al. (2004). The SAPS was loaded with two pre-combusted (500°C; 4 hours) GF/F filters (293 mm diameter) and the pump attached to the frame of the Niskin array for deployment. Once the SAPS reached just above the reef, pumping commenced for a set period (18-30 minutes). The pumping efficiency of the SAPS was 600-650 l h^-1. After recovery of the SAPS, the loaded GF/F filters were preserved at -80°C during the cruise and freeze dried upon return to Heriot-Watt University. Elemental analyses of particulate organic carbon (POC) and particulate nitrogen (PN) was carried out at the University of Liverpool using an NC 2500 CE CHN analyser according to the method of Yamamouro and Kayanne (1995).

The data required correction of POC values to account for dissolved organic matter (DOM). The adsorption of DOM to glass-fiber filters and POC is well documented (Abdel-Moati, 1990, Gardner et al., 2003). One way to account for this during SAPS POM analysis is to load two glass fiber filters into SAPS, one directly above the other (Moran et al., 1999). By analyzing the top and bottom filters for total organic carbon (TOC) and total nitrogen (TN) and then subtracting the bottom filter values from the top filter values, the remaining value will account for dissolved organic matter (DOM) adsorption and more accurately represent the POC and PN values of the top filters. However, many of the top SAPS filters during this experiment were torn, allowing POM to pass through to bottom filters (visually determined filter discoloration), resulting in negative values occurring. Therefore, where the filters were torn, an average value for TOC and TN of both filters was used to represent POC and PN values. The methods of Moran et al. (1999) were further modified using an average value of TOC from all bottom filters where the top filter was not torn to correct all non-torn top filters.

References

Abdel-Moati, A. R. 1990. Adsorption of dissolved organic carbon (DOC) on glass fibre filters during particulate organic carbon (POC) determination. Water Research, 24, 2.

Gardner, W. D., Richardson, M. J., Carlson, C. A., Hansell, D. and Mishonov, A. V. 2003. Determining true particulate organic carbon: bottles, pumps and methodologies. Deep-Sea Research II, 50, 10.

Kiriakoulakis, K., Bett, B. J., White, M. and Wolff, G. A. 2004. Organic biogeochemistry of the Darwin Mounds, a deep-water coral ecosystem, of the NE Atlantic. Deep-Sea Research I, 51, 18.

Moran, S. B., Charett, M. A., Pike, S. M. and Wicklund, C. A. 1999. Differences in seawater particulate organic carbon concentration in samples collected using small- and large-volume methods: the importance of DOC adsorption to the filter bank. Marine Chemistry., 67, 11.

Yamamouro, M. and Kayanne, H. 1995. Rapid determination of organic carbon and nitrogen in carbonate-bearing sediments with a Yanco MT-5 CHN analyser. Limnology Oceanography, 40, 5.

Instrumentation

NC 2500 CE CHN analyser

BODC Data Processing Procedures

An excel spreadsheet was submitted to BODC and archived under accession LJM140004. The date and time provided in the cruise report were used to populate the metadata in the database. Variables were assigned BODC parameter codes, and the units were converted. Data were then loaded into BODC's database using established BODC data banking procedures.

The following table shows how the variables were mapped to appropriate BODC parameter codes:

Problem Report

Not relevant to this dataset.

Project Information

UKOARP Theme B: Ocean acidification impacts on sea surface biology, biogeochemistry and climate

The overall aim of this theme is to obtain a quantitative understanding of the impact of ocean acidification (OA) on the surface ocean biology and ecosystem and on the role of the surface ocean within the overall Earth System.

The aims of the theme are:

• To ascertain the impact of OA on planktonic organisms (in terms of physiological impacts, morphology, population abundances and community composition).
• To quantify the impacts of OA on biogeochemical processes affecting the ocean carbon cycle (both directly and indirectly, such as via availability of bio-limiting nutrients).
• To quantify the impacts of OA on the air-sea flux of climate active gases (DMS and N₂O in particular).

The main consortium activities will consist of in-situ measurements on three dedicated cruises, as well as on-deck bioassay experiments probing the response of the in-situ community to elevated CO₂. Most of the planned work will be carried out on the three cruises to locations with strong gradients in seawater carbon chemistry and pH; the Arctic Ocean, around the British Isles and the Southern Ocean.

Weblink: http://www.oceanacidification.org.uk/research_programme/surface_ocean.aspx

Data Activity or Cruise Information

Data Activity

BODC Sample Metadata Report for JC073_SAP_SAP6

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.

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: