Metadata Report for BODC Series Reference Number 2213782

• 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 Quality Report of Microcat-ODO data from mooring RTEB1, May 2017 to July 2018, deployed on cruise DY078

Screening and Quality Control

Dissolved Oxygen data was processed by removing any pressure-related drift for the 1600 m deployment only. The microcat (S/N:14987) deployed at 950 m has null oxygen values from the 9th June 2018 to the end of the deployment (7th July 2018), this was because the thermistor within the dissolved oxygen unit failed, giving very unrealistic dissolved oxygen concentrations. It was not possible to correct for this or recalculate the dissolved oxygen values using data from the CTD unit, so the end of the data stream has been removed from the file.

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

Sea-Bird SBE 37 SMP-ODO {MicroCAT-CTP-DO} (submersible) CTD logger

A high accuracy conductivity and temperature recorder with an integrated pressure sensor and Optical Dissoved Oxygen sensor (ODO) designed for deployment on moorings. The SM model uses a serial interface (SM) for real-time data transmissions and has internal batteries. The device is fitted with an integral pump (P).

For more information, please see this document: https://www.bodc.ac.uk/data/documents/nodb/pdf/SeaBird-datasheet-SBE37-SMP-ODO-July18.pdf

Processing by BODC of Microcat-ODO data from mooring RTEB1, May 2017 to July 2018, deployed on cruise DY078

BODC Data Processing Procedures

The data was supplied to BODC via three ASCII files which were loaded into the BODC database using established BODC data banking procedures. A parameter mapping table is provided below:

Following transfer the data were screened using BODC in-house visualisation software. Any suspect data were flagged using the BODC quality control flags.

Processing by Originator of Microcat-ODO data from mooring RTEB1, May 2017 to July 2018, deployed on cruise DY078

Sampling Strategy

The data contains recordings of Temperature, Salinity, Pressure and Dissolved Oxygen, which were collected from three SBE37-ODO MicroCATs, fitted on the RTEB1 mooring line situated in the Eastern Boundary array (Rockall Trough) at a nominal position of 57.1005°N - -9.563833°W, which were deployed on 13th May 2017 during the RRS Discovery cruise DY078. These were recovered on the 7th July 2018 by the RV Neil Armstrong cruise AR30-04. The data were collected as part of UK OSNAP (Overturning in the Subpolar North Atlantic Programme) project.

Data Acquisition and Initial Processing

The MicroCATs were synchronised with GPS time (UTC) and were originally set to sample every 1,800 seconds. The SBE37-ODO MicroCAT sensors were fitted with SBE63 Optical dissolved Oxygen Sensors which require a longer flushing time for better accuracy. All 3 SBE37 sensors had the adaptive sampling turned on to provide the best accuracy from a longer required flush. Energy use from the pump time was significantly higher than standard MicroCATs, so their endurance were calculated via the spreadsheet from RAPID. New lithium batteries were fitted and the sensors were deployed at three different depths which affect the overall required pumping time, calculated for 18 months of deployment, as outlined in the table below:

The data were downloaded upon recovery of the mooring. The data were calibrated to a pre-deployment and post-recovery calibration dip and processed. For the 1600 m deployment, dissolved oxygen data were processed by removing any pressure-related drift and then calibrating in-situ to a calibrated lowered dissolved oxygen sensor. The processed data were supplied to BODC for banking.

DY078 Cruise report

Further information can be found in the DY078 Cruise report.

Project Information

UK - Overturning in the Subpolar North Atlantic Programme (UK-OSNAP) Programme

UK-OSNAP is part of an international collaboration to establish a transoceanic observing system in the subpolar North Atlantic. The aim is to quantify and understand the Subpolar Gyre's response to local and remote forcing of mass, heat and freshwater fluxes, within the conceptual framework of the Atlantic Meridional Overturning Circulation (AMOC).

UK-OSNAP is developing a new observing system to provide a continuous record of full-depth, trans-basin mass, heat, and freshwater fluxes. Combining these sustained measurements with innovative modelling techniques will enable the project to characterise the circulation and fluxes of the North Atlantic Subpolar Gyre.

UK-OSNAP is funded by the Natural Environment Research Council (NERC). The project is led by the National Oceanography Centre (NOC) with partners in the University of Liverpool, the University of Oxford and the Scottish Association for Marine Science (SAMS). It is a part of international OSNAP that is led by USA and includes 10 further partner groups in Canada, France, Germany, the Netherlands and China. The project involves fieldwork at sea and model studies.

The OSNAP observing system consists of two legs: one extending from southern Labrador to the southwestern tip of Greenland across the mouth of the Labrador Sea (OSNAP West), and the second from the southeastern tip of Greenland to Scotland (OSNAP East). The observing system also includes subsurface floats (OSNAP Floats) in order to trace the pathways of overflow waters in the basin and to assess the connectivity of currents crossing the OSNAP line.

NERC have added an extension to UK-OSNAP, until October 2024. This will result in the UK-OSNAP-Decade: 10 years of observing and understanding the overturning circulation in the subpolar North Atlantic (2014-2024).

Data Activity or Cruise Information

Data Activity

OSNAP Moored Instruments EB1 2017-2018

This rig was deployed as part of the Rockall Trough array of the "Overturning in the Subpolar North Atlantic Programme" (UK-OSNAP).

The rig was held down by an 2100 kilogram anchor on the seabed at 1800 metres depth. It was kept erect by 40" syntactic float at 488 metres depth and a 31" syntactic float at 96 metres depth.

The instruments deployed on the rig were as follows:

ATLAS and AtlantOS funded sensors

Some of the sensors deployed on mooring RTEB1 were funded by ATLAS and AtlantOS. These were:

• McLane RAS water sampler at 50 m (funded ATLAS)
• SBE Deep SeapHOx (CTD + O2 + pH) at 50 m (funded ATLAS)
• SBE SMP37 ODO (CTD + O2) at 750 m, 950 m and 1600 m (2 funded ATLAS, 1 funded AtlantOS)

The funding acknowledgement for the ATLAS and AtlantOS sensor data is:

'This project has received funding from the European Union's Horizon 2020 research and innovation programme, under grant agreement No 678760 (ATLAS) and No 633211 (AtlantOs). This output reflects only the author's view and the European Union cannot be held responsible for any use that may be made of the information contained therein.'

Related Data Activity activities are detailed in Appendix 1

Cruise

Complete Cruise Metadata Report is available here

Fixed Station Information

Fixed Station Information

UK-OSNAP/Ellett Array Mooring RTEB1 (OM57)

Mooring RTEB1 (called OM57 by the International OSNAP Community) forms part of the OSNAP-East Transect and, from 2018, the Ellett Array. It was first deployed on 18^th July 2014 by the UK-OSNAP Community.

It is located at 57.0993°N, 9.5480°W where there is a water depth of 1975m

Between 2014 and 2018 this mooring was funded by UK-OSNAP, from 2018 it was funded as part of the Ellett Array by CLASS (Climate Linked Atlantic Sector Science).

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: RTEB1_04_2017

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: UK-OSNAP/Ellett Array Mooring RTEB1 (OM57)

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.