BGS Hosted Metadata
Subglacial bed roughness of Greenland, provided using two independent metrics
These two files (.csv) provide independent methods of quantifying subglacial roughness in Greenland, both calculated from radio-echo sounding (or ice penetrating radar) data collected by the Operation Ice Bridge programme using CReSIS instrumentation. They are an output of the Basal Properties of Greenland (BPOG) project ( http://bpog.blogs.ilrt.org/), with funding from NERC grant NE/M000869/1.
Roughness here, and in the wider literature, is defined as the variation in bed elevation (in the vertical) at the ice-bed interface, over a given length-scale. These two metrics calculate/quantify this variation in different ways: one shows topographic-scale roughness, calculated from the variation in along-track topography (bed elevation measurements derived from the radar pulse); and the other shows scattering-derived roughness, calculated from quantifying characteristics of each bed-echo (the return from the radar pulse at the ice-bed interface).
Simple
- Date (Creation)
- 2018-02-02
- Date (Revision)
- 2018-02-02
- Date (Publication)
- 2018-02-02
- Date (released)
- 2018-02-02
- Edition
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None
- Unique resource identifier
- https://doi.org/10.5285/6071926f-32e0-4681-a50d-aab08f42c08a
- Codespace
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doi
- Unique resource identifier
- GB/NERC/BAS/PDC/01060
- Codespace
- Unique resource identifier
- NE/M000869/1
- Codespace
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award
- Other citation details
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Please cite this item as: Cooper, M., & Jordan, T. (2018). Subglacial bed roughness of Greenland, provided using two independent metrics (Version None) [Data set]. Polar Data Centre, Natural Environment Research Council, UK. https://doi.org/10.5285/6071926f-32e0-4681-a50d-aab08f42c08a
- Credit
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No credit.
- Status
- Completed
- Point of contact
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Organisation name Individual name Electronic mail address Role Univeristy of Bristol
Jordan, Tom
Author Imperial College London
Siegert, Martin
Author University of Bristol
Williams, Chris
Author University of Bristol
Bamber, Jonathan
Author University of Bristol
Cooper, Michael
Author Stanford University
Schroeder, Dustin
Author NERC EDS UK Polar Data Centre Point of contact
- Maintenance and update frequency
- As needed
- Maintenance note
- Completed
- Theme
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Geophysics
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Ice penetrating radar
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Radio-echo sounding
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Scattering
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Subglacial roughness
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Topography
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- Place
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Greenland Arctic
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GEMET - INSPIRE themes, version 1.0
- Access constraints
- Other restrictions
- Other constraints
- no limitations to public access
- Access constraints
- Other restrictions
- Other constraints
- no limitations
- Use constraints
- License
- Other constraints
- Open Government Licence v3.0
- Use constraints
- Other restrictions
- Other constraints
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This data is governed by the NERC Data Policy: https://www.ukri.org/who-we-are/nerc/our-policies-and-standards/nerc-data-policy/
- Use constraints
- Other restrictions
- Other constraints
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This data is governed by the NERC data policy and supplied under Open Government Licence v.3
- Use constraints
- Other restrictions
- Other constraints
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No restrictions apply.
- Unique resource identifier
- url
- Codespace
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url
- Association Type
- Larger work citation
- Unique resource identifier
- url
- Codespace
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url
- Association Type
- Cross reference
- Spatial representation type
- Text, table
- Language
- English
- Character set
- UTF8
- Topic category
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- Environment
- Geoscientific information
))
- Begin date
- 1993-01-01
- End date
- 2016-12-31
- Supplemental Information
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It is recommended that careful attention be paid to the contents of any data, and that the author be contacted with any questions regarding appropriate use. If you find any errors or omissions, please report them to polardatacentre@bas.ac.uk.
- Title
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European Petroleum Survey Group (EPSG) Geodetic Parameter Registry
- Date (Publication)
- 2008-11-12
- Cited responsible party
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Organisation name Individual name Electronic mail address Role European Petroleum Survey Group
Publisher
- Unique resource identifier
- urn:ogc:def:crs:EPSG::3031
- Version
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6.18.3
Distributor
- Distributor contact
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Organisation name Individual name Electronic mail address Role NERC EDS UK Polar Data Centre Distributor
- Units of distribution
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bytes
- Transfer size
- 1
- OnLine resource
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Protocol Linkage Name WWW:LINK-1.0-http--link
https://ramadda.data.bas.ac.uk/repository/entry/show/?entryid=6071926f-32e0-4681-a50d-aab08f42c08a Get Data
- Hierarchy level
- Dataset
- Statement
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Methodology:
The first file, TopoR_icemask.csv, shows topographic-scale roughness, calculated from the variation in along-track topography (bed elevation measurements derived from the radar pulse) at a 200 m length-scale (the bin size used). This dataset presents the spatial pattern of roughness beneath the ice, clipped to ice mask, and filtered with respect to direction of flow. As this data is filtered with respect to flow, it allows for study of anisotropy in roughness (with regards to surface flow direction).
TopoR_icemask.csv includes data from all seasons from 1993 - 2016 campaigns. This dataset is derived using a moving 'bin' to calculate root mean square (rms) height for CReSIS along-track topography data (L2 RDS data). The flow filtering is done using Joughin et al (2016b) ice surface velocity mosaic.
The second file, ScatR_icemask.csv, shows scattering-derived roughness, calculated from quantifying characteristics of each bed-echo (the return from the radar pulse at the ice-bed interface). A roughness 'value' (expressed in 'metres') is inverted from the 'abruptness' (or pulse peakiness) of the bed return using a scattering model. Theoretically, this dataset presents the spatial pattern of roughness sensitive to roughness between the scale of the wavelength (order meter) and the Fresnel zone (order hundred meters) beneath the ice, clipped to ice mask. The 'scattering derived' roughness provides a more fine-scale roughness value (i.e. presents more information about roughness at scales less that 200 m).
ScatR_icemask.csv includes data from CReSIS seasons: 2011-2014 P3; 2011 TO, 2009 TO, 2008 TO, 2006 TO, 2005 TO, 2010 DC8. This dataset is calculated from bed-echo characteristics, using a scattering model, to invert rms height (scattering-derived roughness) from waveform abruptness; this is calculated using the CReSIS data (L1 RDS).
For the complete methodology, please see Cooper et al. (in prep.)
Data collection:
Data was collected with a Multichannel Coherent Radar Depth Sounder (MCoRDS) developed by the Center for Remote Sensing of Ice Sheets (CReSIS).
Data quality:
Quality control was taken from the original data source; only 'csv_good' files were used, and where appropriate 'high quality' picks, as per the CReSIS radar depth sounder documentation (see ftp://data.cresis.ku.edu/data/rds/rds_readme.pdf). 'csv_good' files only contain data points where the ice surface and ice bottom were detected.
Both datasets are point data. For TopoR_icemask.csv, each point is the mid-point of a 200 m 'bin'.
Metadata
- File identifier
- 6071926f-32e0-4681-a50d-aab08f42c08a XML
- Metadata language
- English
- Character set
- UTF8
- Hierarchy level
- Dataset
- Hierarchy level name
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dataset
- Date stamp
- 2018-02-02
- Metadata standard name
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ISO 19115 Geographic Information - Metadata
- Metadata standard version
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ISO 19115:2003(E)
- Metadata author
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Organisation name Individual name Electronic mail address Role NERC EDS UK Polar Data Centre Point of contact
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