Ice Flow History of the Thwaites Glacier, West Antarctica

Summary

This data set contains past flow lines of Thwaites Glacier. The flow lines were identified using layer patterns tracked between parallel radar layers, from a radar profile of the Thwaites Glacier catchment. The radar data was run and processed by the University of Texas Institute for Geophysics. The flow lines were identified using internal layer patterns detected with radar. The patterns in the internal layers of glaciers were created upstream, and over time moved downstream.

Data are available via FTP in ASCII text (.txt) format.

Citing These Data

The following example shows how to cite the use of this data set in a publication. For more information, see our Use and Copyright Web page.

The following example shows how to cite the use of this data set in a publication. List the principal investigators, year of data set release, data set title, publisher: NSIDC, and digital media.

Conway, H., G. Catania, and T. J. Fudge. 2010. Ice Flow History of the Thwaites Glacier, West Antarctica. Boulder, Colorado, USA: National Snow and Ice Data Center. http://dx.doi.org/10.7265/N5RR1W6X.

Overview Table

Category	Description
Data format	Data are in ASCII text (.txt) format
Spatial coverage and resolution	Southernmost Latitude: 79.7°S Northernmost Latitude: 76°S Westernmost Longitude: 99.5°W Easternmost Longitude: 123°W
Temporal coverage and resolution	Radar data were collected during the 2004 to 2005 Antarctic field season (October through February).
File naming convention	paleo_flow_line_picks.txt
File size	The data set consists of one 13 KB file.
Parameter(s)	X and Y coordinates that define a glacier flow line.
Procedures for obtaining data	Data are available via FTP.

Table of Contents

1. Contacts and Acknowledgments
2. Detailed Data Description
3. Data Access and Tools
4. Data Acquisition and Processing
5. References and Related Publications
6. Document Information

1. Contacts and Acknowledgments

Investigators

Dr. Howard Conway
Department of Earth and Space Sciences
University of Washington
Johnson Hall Rm-070, Box 351310
4000 15th Avenue NE
Seattle, WA 98195
USA

Dr. Ginny Catania
University of Texas Institute of Geophysics
J.J. Pickle Research Campus, Bldg. 196
10100 Burnet Road (R2200)
Austin, TX 78758
USA

T. J. Fudge
Department of Earth and Space Sciences
University of Washington
Johnson Hall
4000 15th Avenue NE
Seattle, WA 98195
USA

Technical Contact

Acknowledgements

This research was supported by NSF OPP grant 0739372.

2. Detailed Data Description

Format

This data set consists of one data file in ASCII text (.txt) format.

File and Directory Structure

Data are available on the FTP site in the ftp://sidads.colorado.edu/pub/DATASETS/AGDC/conway_nsidc_0463/ directory. The data set consists of one file, paleo_flow_line_picks.txt, which contains flow line data derived from a radar sounding of Thwaites Glacier in West Antarctica.

File Size

The data file is 13 KB.

Spatial Coverage

The data were derived using radar sounding data collected from Thwaites Glacier in West Antarctica.

Southernmost Latitude: 79.7°S
Northernmost Latitude: 76°S
Westernmost Longitude: 99.5°W
Easternmost Longitude: 123°W

Temporal Coverage

The radar data that support this investigation were collected by the University of Texas Institute for Geophysics during the Antarctic field season (October through February) in 2004 to 2005.

Parameter or Variable

The data set contains a table of coordinates that define flow lines derived from a radar sounding of Thwaites Glacier in West Antarctica.

Parameter Description

Each row contains two pairs of x and y coordinates, which form one flow line. Coordinates are in polar stereographic with units of kilometers (km). The parallel of true scale is 71°S.

Sample Data Record

x1	y1	x2	y2
-1.3438309e+003	-5.8595677e+002	-1.3461408e+003	-5.7038227e+002
-1.3388820e+003	-5.8459680e+002	-1.3409560e+003	-5.6897531e+002
-1.3364551e+003	-5.8392782e+002	-1.3391090e+003	-5.6846833e+002

3. Data Access and Tools

Data Access

Data are available via FTP.

Volume

The total volume of the data set is 13 KB.

Software and Tools

Data are accessible using spreadsheet software.

Related Data Collections

• Airborne Laser Altimetry of the Thwaites Glacier Catchment, West Antarctica
• US International Trans-Antarctic Scientific Expedition 400 MHz Subsurface Radar Profiles

4. Data Acquisition and Processing

Theory of Measurements

Researchers identified past glacial flow lines for Thwaites Glacier in Antarctica using internal layer patterns detected with radar. The patterns in the internal layers of glaciers were created upstream, and over time moved downstream. By looking at the pattern between radar lines, researchers can discern the direction and timescale of past flow. The technique is described in more detail in Ng and Conway, 2004.

 

5. References and Related Publications

Holt, J. W., D. D. Blankenship, D. L. Morse, D. A. Young, M. E. Peters, S. D. Kempf, T. G. Richter, D. G. Vaughan, and H. F.J. Corr. 2006. New Boundary Conditions for the West Antarctic Ice Sheet: Subglacial Topography of the Thwaites and Smith Glacier Catchments. Geophysical Research Letters, Vol. 33, L09502, doi: 10.1029/2005GL025561.

Ng, F. and H. Conway. 2004. Fast-Flow Signature in the Stagnated Kamb Ice Stream. Geological Society of America 32:6, p. 481-484, doi:10.1130/G20317.1.

Table 1 lists related documents that are available online:

Table 1. Related Documents

Document	Description	URL
Antarctic Glaciological Data Center Web site	Data Center Web site	http://nsidc.org/agdc/

6. Document Information

Acronyms

The acronyms used in this document are listed in Table 2.

Table 2. Acronyms and Abbreviations

Acronym	Description
FTP	File Transfer Protocol
NSIDC	National Snow and Ice Data Center
URL	Uniform Resource Locator

Document Creation Date

28 April 2010

Document URL

http://nsidc.org/data/docs/nsidc0463_conway/index.html