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Data Set ID:

US International Trans-Antarctic Scientific Expedition (US ITASE): GPR Profiles and Accumulation Mapping, Version 1

Snow accumulation rates typically show high variability over short distances. This data set contains accumulation rates using ground-penetrating radar (GPR) to detect isochronal layers in the firn in West Antarctica. These layers were then dated using results from ice core analyses. These data show that accumulation rates along this profile have decreased in recent decades. The radar profile extends between two ice core sites taken along one of the US-ITASE traverse routes.

Data are available via FTP in both ASCII and Excel formats.

Geographic Coverage

  • Glaciers/Ice Sheets > Ablation Zones/Accumulation Zones
  • Glaciers/Ice Sheets > Ice Sheets
Spatial Coverage:
  • N: -77.6832, S: -78.0832, E: -120.082, W: -123.993

Spatial Resolution: Not Specified
Temporal Coverage:
  • 1 December 2000 to 31 December 2000
Temporal Resolution: Not specified
Data Format(s):
  • ASCII Text
Sensor(s): GPR
Version: V1
Data Contributor(s): Vandy Spikes, Gordon Hamilton, Paul Mayewski, Steven Arcone, Susan Kaspari

Data Citation

As a condition of using these data, you must cite the use of this data set using the following citation. For more information, see our Use and Copyright Web page.

Spikes, V. B., G. S. Hamilton, P. A. Mayewski, S. Arcone, and S. Kaspari. 2005. US International Trans-Antarctic Scientific Expedition (US ITASE): GPR Profiles and Accumulation Mapping, Version 1. [Indicate subset used]. Boulder, Colorado USA. NSIDC: National Snow and Ice Data Center. doi: [Date Accessed].

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Detailed Data Description


Data are available as a tab-delimited ASCII file and an Excel spreadsheet.

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Study Area Location Map

The below map shows the location of the study area. The dashed lines are ITASE traverse routes. The solid line represents the section of the traverse between ice core sites 00-4 and 00-5, the GPR transect. The figure and caption are taken from Spikes et al. (2004).

Map: Location of US ITASE core sites 00-4 and 00-5
Location maps and ice core data. a) Continent-scale map of Antarctica. b) Portion of West Antarctica (boxed region in a) showing some of the US ITASE traverse routes (white lines). Red circles indicate where ice cores were collected. The solid white line represents the transect along which the radar profile was collected between 00-4 and 00-5. The white arrow indicates the direction of travel during data acquisition. The shaded relief map was generated from a digital elevation model (Liu et al. 1999), which was also used to estimate ice flow directions at 00-4 and 00-5 (black arrows). c) Ice core density and chemistry (nssSO42-) profiles for 00-4 (blue) and 00-5 (red).

See Absolute Earth™ - Antarctic Snow Accumulation to download an interactive map of Antarctica that shows ice core locations. Absolute Earth™ is a proprietary line of Global Information Systems used to gather, process, store, manipulate, interpret, visualize, and disseminate any georeferenced data. Absolute Earth products are intended to make geographically-based information available to all people, regardless of background or skill level. These extremely flexible products merge advanced web applications with desktop software, network databases, and Earth visualization technologies.

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File Size

ITASE_accumulation_004_005.txt: 1.1MB
ITASE_accumulation_004_005.xls: 2.0MB

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Spatial Coverage

The distance along the transect is 100 km.

Core Site 00-4 Location: 78.0832°S 120.082°W
Core Site 00-5 Location: 77.6832°S 123.993°W
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Temporal Coverage

Data were collected in December 2000.

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Parameter or Variable

Sample Data Record

Traces were measured from core 00-4 to 00-5. Time is given in seconds for the day tied to GMT. Distance is in km along the track. Accumulation rates are presented as water equivalent (m/year). The years represent either a horizon age (for example, 1966, which is the amount of accumulation that occurred between 1966 and 2000) or the amount of accumulation between two horizons (for example, 1941-1966).

Trace# Time(sec) Longitude Latitude X(km) Y(km) Elevation(m) Distance(km) 1966(m/a) 1941(m/a) 1893(m/a) 1848(m/a) 1815(m/a) 1941-1966 1893-1941 1848-1893 1815-1848
1 85265.7 -120.0821281 -78.08317476 -1124.287 -651.258 1697.19 0.04 0.18671053 0.19447709 0.19273349 0.19189462 0.19329594 0.20535027 0.19055399 0.18988135 0.19979295
2 85270.3 -120.0822793 -78.08315856 -1124.287 -651.262 1697.19 0.05 0.1867103 0.19447698 0.19273351 0.19189469 0.19329601 0.20535033 0.19055417 0.18988153 0.19979305
3 85275 -120.0824306 -78.08314236 -1124.286 -651.265 1697.19 0.05 0.18671364 0.19447698 0.19273351 0.19189469 0.19329601 0.20534566 0.19055417 0.18988153 0.19979305
4 85279.7 -120.0825818 -78.08312616 -1124.286 -651.269 1697.18 0.06 0.18675183 0.19447688 0.19273353 0.19189476 0.19329609 0.20529195 0.19055434 0.1898817 0.19979316
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Software and Tools

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Data Acquisition and Processing

Data were acquired using ground-penetrating radar (GPR). The isochronal layers in the firn were dated using results from ice core analyses.

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References and Related Publications

Contacts and Acknowledgments

Vandy B. Spikes, Gordon S. Hamilton, Paul A. Mayewski, and Susan Kaspari 
Climate Change Institute 
Department of Earth Sciences
University of Maine 
Orono, ME, USA

Steven A. Arcone 
U.S. Army ERDC, Cold Regions Research and Engineering Laboratory 
Hanover, NH, USA


This research was supported by:

  • Distribution of Snow Accumulation and Mass Balance across the West Antarctic Ice Sheet. Principal Investigator: Vandy Blue Spikes, University of Maine. NASA Fellowship Award Number ESS/01-0000-0097.

  • High Resolution Radar Profiling of the Snow and Ice Stratigraphy beneath the ITASE Traverses, West Antarctic Ice Sheet. Principal Investigator: Steven A. Arcone, U.S. Army Cold Regions Research and Engineering Laboratory. National Science Foundation OPP award #0088035

  • Mass Balance and Accumulation Rate Along US ITASE Routes. Principal Investigator: Gordon S. Hamilton, University of Maine. National Science Foundation OPP award #0196441

  • US ITASE Glaciochemistry. Principal Investigator: Paul A. Mayewski, University of Maine. National Science Foundation OPP award #0096299

  • US ITASE SMO: A Collaborative Program of Research from South Pole to Northern Victoria Land. Pinciple Investigator: Paul A. Mayewski, University of Maine. National Science Foundation OPP award #0229573

Document Information


March 2005

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