Residual surface elevation texture model of the grounded Antarctic Ice Sheet - VERSION 1.0
GB/NERC/BAS/PDC/02257
Abstract:
This dataset provides a continent-wide model of Residual Surface Elevation (RSE) across the grounded Antarctic Ice Sheet. RSE represents kilometre- to regional-scale variations in ice-surface elevation relative to a modelled, long-wavelength ice-sheet surface. These variations provide a spatially continuous representation of ice-surface texture that can be used to investigate the planform organisation of subglacial geomorphology. The dataset was derived from the GaplessREMA100 digital elevation model. Raster values are expressed in metres.
Funding was provided by the IAPETUS2 Doctoral training program NE/S007431/1
Citation:
Hazzard, H. (2026). Residual surface elevation texture model of the grounded Antarctic Ice Sheet - VERSION 1.0 (Version 1.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/31db8049-2d2c-481d-922b-02f706932f0e
Access Data
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License
| Access: | Data is under embargo until publication of paper |
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| Use: | This data is governed by the NERC data policy (http://www.nerc.ac.uk/research/sites/data/policy/) and supplied under Open Government Licence v.3 (http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/). |
Basic Information
| Creation Date: | 2026-08-14 |
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| Dataset Progress: | Complete |
| Dataset Language: | English |
| ISO Topic Categories: |
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| Parameters: |
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Additional Information
| Quality: | The RSE was compared qualitatively with Bedmap3 bed topography and available airborne radio-echo sounding profiles. Selected Bedmap3 and RSE profiles were also assessed using continuous wavelet coherence to examine the spatial wavelengths over which their broad topographic behaviour corresponded. The RSE is correlated with bed topography discretely at short wavelengths (1 - 10km) and broadly with larger scale (10 - 50 km) features such as regional basins. RSE is not a direct measurement or inversion of bed elevation. The product should therefore be interpreted alongside radar observations and existing bed-elevation datasets wherever possible. Areas outside the grounded ice sheet are assigned a no data value of 32767. No formal vertical error estimate is assigned, but we refer to the error assessments of REMA and Gapless-REMA100 in Howatt et al., 2019 and Dong et al., 2022. |
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| Lineage/Methodology: | The Antarctic Residual Surface Elevation model, (version 1.0), was derived from the 100 m Gapless-REMA100 digital elevation model. GaplessREMA100 was clipped to the grounded Antarctic Ice Sheet using the Bedmap3 grounding-line mask. Exposed rock outcrops were removed using the Antarctic Digital Database rock-outcrop inventory. Remaining no-data cells were excluded from the calculations. A third-order polynomial function was fitted to all valid ice-surface elevations to approximate the broad, continent-scale geometry of the Antarctic Ice Sheet, followed by a secondary, second order local corrective function. The local corrections were combined with the continent-wide polynomial surface to produce an idealised ice-sheet geometry. Discontinuities between local polynomial tiles were suppressed by applying a Gaussian smoothing kernel with a standard deviation of 500 pixels, equivalent to 50 km. The final RSE raster was calculated by subtracting this smoothed idealised ice-sheet surface from GaplessREMA100. Positive RSE values indicate locations where the observed ice surface lies above the fitted long-wavelength surface, whereas negative values indicate locations where it lies below it. |
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REFERENCE MATERIALS:
Extent
| Spatial Coverage: | |
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| Latitude | |
| Southernmost | -90 |
| Northernmost | -60 |
| Longitude | |
| Westernmost | -180 |
| Easternmost | 180 |
| Altitude | |
| Min Altitude | N/A |
| Max Altitude | N/A |
| Depth | |
| Min Depth | N/A |
| Max Depth | N/A |
| Data Resolution: | |
| Latitude Resolution | 100m |
| Longitude Resolution | 100m |
| Horizontal Resolution Range | N/A |
| Vertical Resolution | N/A |
| Vertical Resolution Range | N/A |
| Temporal Resolution | N/A |
| Temporal Resolution Range | N/A |
| Location: | |
| Location | Antarctica |
| Detailed Location | East Antarctic ice sheet, West Antarctic ice sheet |
Instrumentation
| Data Collection: | The Residual Surface Elevation dataset was processed using MATLAB R2023a. Mapping Toolbox Version 5.5 was used to read, handle and export georeferenced GeoTIFF raster outputs in Antarctic Polar Stereographic coordinates (EPSG:3031). The Image Processing Toolbox Version 11.7 was used to construct and apply the Gaussian smoothing filter which suppresses discontinuities at tile edges. Polynomial surface fitting and least-squares optimisation were performed using standard MATLAB functions. |
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Storage
| Distribution: | |
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| Distribution Media | Online Internet (HTTP) |
| Distribution Size | 645 MB |
| Distribution Format | TIFF |
| Fees | N/A |
| Data Storage: | 1 x GeoTIFF file totalling 645 MB |