Metadata Report for BODC Series Reference Number 1927124

• 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

Sea-Bird SBE 37-SMP MicroCAT

The SBE 37-SMP MicroCAT is a high accuracy conductivity and temperature recorder (pressure optional) with Serial interface, internal battery, non-volatile FLASH Memory and integral Pump. The Integral Pump runs for 1 second each time the MicroCAT samples, improving the conductivity response and giving improved anti-foul protection.

Designed for moorings and other long-duration, fixed-site deployments, MicroCATs have non-corroding titanium housings rated for operation to 7000 meters or pressure sensor full scale-range. Communication with the MicroCAT is over an internal, 3-wire, RS-232C link. The MicroCAT's aged and pressure-protected thermistor has a long history of exceptional accuracy and stability (typical drift is less than 0.002°C per year). Electrical isolation of the conductivity electronics eliminates any possibility of ground-loop noise.

Specifications

Further information can be found via the following link: Sea-Bird SBE 37-SMP MicroCAT Datasheet

Processing by BODC of OSNAP Moored MicroCATs: PE400

The SBE37 MicroCAT data arrived at BODC in 29 ASCII files representing the data collected from MicroCAT sensors deployed on the M1-M5 moorings during cruise PE400.

During transfer to BODC internal format (QXF) the originator's variables were mapped to unique BODC parameter codes. The following table shows the parameter mapping:

The reformatted data were visualised using the in-house software. Any suspect data were flagged, using the BODC quality control flags.

Processing by originator of OSNAP MicroCATs on moorings M1-5 deployed in 2015

Sampling Strategy

During the RV Pelagia cruise PE400, Seabird MicroCATs were deployed on five moorings (M1, M2, M3, M4 and M5) to record temperature, salinity and pressure. These moorings were recovered during the RRS Discovery cruise DY054.

Mooring operations were conducted from the aft deck using a Lebus double-barrelled winch.

Data Acquisition and Initial Processing

The MicroCATs were calibrated against the CTD sensors. The MicroCATs were positioned on the CTD rosette and deployed before and after deployment on the mooring. Data recorded by the MicroCATs and data recorded by the CTD sensors were compared at bottle stops which were about 5 minutes each.

The processed data were supplied to BODC for banking.

Problem report

SN 11287 appeared to have a large drift during the year on M2. During the calibration dip this instrument had a larger variability in conductivity than the other instruments.

11338 had a temperature offset of 0.003°C during the calibration dip.

10560 had a low conductivity for data cycles 5455-5550 and 7382-7390.

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 Instrument M1 2015-2016

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

The rig was held down by an 1900 kilogram anchor on the seabed at 2080 metres depth. It was kept erect by 44" syntactic float at 43 metres depth and a 31" syntactic float at 283 metres depth.

The instruments deployed on the rig were as follows:

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 Mooring M1 (OM31)

Mooring M1 (called OM31 by the International OSNAP Community) forms part of the OSNAP-East Transect. It was first deployed on 11^th August 2014 by the UK-OSNAP Community.

It is located at 59.9041°N, 41.1402°W where there is a water depth of 2059m

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: OSNAP_NOC_M1_PE400_201507

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 Mooring M1 (OM31)

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.