Metadata Report for BODC Series Reference Number 1748661

• 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

Quality report - iSTAR Moorings

It is clear from data from pressure sensors (and other sensors measuring the orientation of instruments on the mooring) that the iSTAR moorings were occasionally displaced in the water column. Given the location of the mooring it is likely that this disruption was caused by ice bergs knocking in to the mooring array. This was particularly noticeable in the data from moorings iSTAR6 (where the array became ~ 60m deeper on 05 January 2013), iSTAR9 (where the array became ~ 10 m deeper between 14 and 17 November 2013) and PIG_S (where the array became ~ 50 m deeper on the 20 July 2014 and then ~50 m deeper again on 30 July 2015).

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

RD Instruments 300kHz Workhorse Sentinel Acoustic Doppler Current Profiler

Specifications

The manufacturer's specification document can be found here

BODC Processing - iSTAR Moored RDI ADCP

Data were received by BODC in Matlab files, with one file containing all data from an iSTAR mooring array. The data were reformatted to QXF (a NetCDF file format) by in house software. A separate QXF file was created for data from each instrument. Metadata were also extracted from the originator's file and used to populate the BODC database.

The following tables shows how the variables within the files were mapped to appropriate BODC parameter codes:

Due to the volume of data supplied the datasets have been stored as yearly files (so a mooring that was deployed in 2012 and recovered in 2014 will have been split in to three datasets).

Following transfer to QXF, the data were quality controlled using BODC's in-house visualisation software.

Originator's processing - iSTAR Moored RDI ADCPs

Data processing

The originator calibrated data from the moorings with data from CTD casts taken at deployment and recovery. Instrument depths have been corrected based on pressure data from adjacent instruments. Corrections have not been made for speed of sound, as these corrections were estimated by the originator to be insignificant. Where appropriate temperature and pressure offsets were applied (these are documented in the table below.

The magnetic variation calculated from the International Geomagnetic Reference Field (IGRF) at each mooring position on 01 January 2013 was recorded. The following variables had magnetic variation corrections applied by the originator:

• current direction
• northward component of current
• eastward component of current

Magnetic variation corrections weren't applied to heading

The full data from ADCP s/n 15460 on iSTAR7 have not been ingested by BODC, because of the large amounts of data this instrument recorded. The data in the file supplied by the originator that BODC ingested are the averages of each hourly four-minute burst (of 120 ensembles, each containing four 2-Hz pings).

Offsets applied

Echo intensity coefficients

The echo intensity data were provided to BODC by the originator with units of counts. This unit is a proprietary unit, but it is proportional to decibels (dB). The manufacturer has supplied coefficients for each ADCP and each beam (Kc coefficient) which can be used to calibrate and convert the echo intensity from units of Count to units of dB. BODC has not applied these coefficients, but they are available in the table below (so that an end-user can decide what is best for their processing needs).

Project Information

The Ice Sheet Stability (iSTAR) programme

Background and objectives

The iSTAR programme aims to measure the rate that ice is being lost from the West Antarctic ice sheet, and to improve our understanding of what might be driving this loss how it is changing over time. The rate of loss of water from ice in glaciers in the Antarctic (and Greenland) is more than the amount of water being deposited in these areas by precipitation. This has changed our understanding of these systems and the rate of ice loss is a matter of interest for sea level and climate research. Improving our understanding of the processes and impacts of changes to these systems is vital for better predictions for sea level rise in the future and will feed in to climate research. This programme combines scientific research of glaciers and the surrounding ocean environment (including how they impact each other). Research about the oceans was focused on the Amundsen Sea Sector of West Antarctica with instruments deployed from the research ship RRS James Clark Ross. Research about the ice was focused on Pine Island Glacier, Thwaites Glacier and Union Glacier with measurements taken during two expeditions across the ice. This programme was funded by the Natural Environment Research Council (NERC)

The programme is split in to four projects:

Ocean2ice: Processes and variability of ocean heat transport toward ice shelves in the Amundsen Sea Embayment (iSTAR A)

Ocean under ice: Ocean circulation and melting beneath the ice shelves of the south-eastern Amundsen Sea (iSTAR B)

Dynamic ice: Dynamical control on the response of Pine Island Glacier (iSTAR C)

Ice loss: The contribution to sea-level rise of the Amundsen Sea sector of Antarctica (iSTAR D)

Participants

The iSTAR research programme is managed by British Antarctic Survey (BAS) on behalf of NERC. Operational support, in the form of logistics planning and infrastructure, and Communication and Knowledge Exchange support are provided by BAS. There are four science projects and participants in these projects represent the following organisations:

• British Antarctic Survey
• National Oceanography Centre
• Newcastle University
• Scott Polar Research Institute
• University College London
• University of Bristol
• University of East Anglia
• University of Edinburgh
• University of Leeds
• University of Southampton
• University of St. Andrews
• University of Tasmania
• University of Washington

Fieldwork and data collection

A wide range of data parameters were collected for this programme. Physical and chemical measurements of the ocean close to and next to the ice shelf were made using instruments deployed from ship, on moorings, on autonomous platforms and seal tags. Measurements were also made of the glaciers and ice shelfs including radar and seismic surveys and ice cores. There were also meteorological and atmospheric measurements taken. For more information about the data collected on each of the four projects see the project web pages.

Data management

Data management for ocean data will be done by the British Oceanographic Data Centre whilst ice data will be managed by the Polar Data Centre.

For more information about iSTAR programme see the: iSTAR Programme Website

Ocean2ice: Processes and variability of ocean heat transport toward ice shelves in the Amundsen Sea Embayment (iSTAR A)

Background and objectives

Ocean2ice (otherwise referred to as iSTAR A) is a project that is part of NERC's Ice Sheet Stability programme. The project was designed to investigate how relatively warm water gets close to and beneath glaciers in the Antarctic and what impact this warm water has on the rate of ice melt at these sites. This research and collection of data will to feed in to climate and sea level forecasting and research. This project was funded by the Natural Environment Research Council.

Participants

The principal investigator for the Ocean2ice project is Professor Karen Heywood, University of East Anglia. Other participants in the project represent the following organisations:

• British Antarctic Survey
• National Oceanography Centre
• University of East Anglia
• University of Southampton
• University of St. Andrews

Fieldwork and data collection

Oceanographic data were collected from a wide range of instruments from the research ship RRS James Clark Ross between 26 January and 08 March 2014 in the Amundsen Sea. Data collected include measurements of the physical conditions (including temperature and salinity), current speeds and directions, chemical measurements of the water column (including oxygen and chlorophyll-a concentrations). A fleet of Seagliders (ocean robots that measure physical parameters including temperature, salinity and current speeds and directions) were also deployed to measure conditions close to the ice shelf. Moorings were deployed by the project and have measured conditions in the area over a couple of years. In addition Seal tags (small sensors glued to the fur of seals which fall off when the seals moult their fur) were deployed and transmit data back via satellite networks to scientists. These seal tag deployments give the scientists the rare opportunity to measure water properties below the ice shelf.

Data management

All data collected by the Ocean2ice project are to be submitted to the British Oceanographic Data Centre for careful storage, quality control, archiving and distribution to scientists, education, industry and the public.

For more information about Ocean2ice see the iSTAR A project page

Data Activity or Cruise Information

Data Activity

PIG_S Mooring

PIG_S is a mooring array deployed for the iSTAR programme. The mooring was deployed from RRS James Clark Ross cruise JR20140126 in February 2014 and were recovered on RV Araon cruise ANA06B in February 2016.

Instrument setup

Related Data Activity activities are detailed in Appendix 1

Cruise

Complete Cruise Metadata Report is available here

Fixed Station Information

Fixed Station Information

iSTAR9 (PIG_S)

Water depth = 810 m

Sampling history

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: PIG_S

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: iSTAR9 (PIG_S)

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.