Ice thickness and internal layer depth data were collected with a ground-based, ice-penetrating radar study as part of the US International Trans-Antarctic Scientific Expedition (US ITASE) traverse in West Antarctica from 01 November 2001 to 10 January 2003. Longitude, latitude, ice thickness, and depth to a prominent internal reflector were collected at approximately 12 m intervals. Ice thickness values are reported for approximately 90% of the traverse, and internal layer depth values are reported for approximately 80% of the traverse. Data are avaialble in ASCII and JPEG formats via FTP.
Get Data
DOWNLOADING DATA VIA FTP
Data can be downloaded through a Web browser or command line via FTP. When using a Web browser, the FTP link first directs you to an Optional Registration Form that if filled out, will allow you to receive notifications about updates or processing changes related to that specific data set. After completing the Optional Registration Form, the FTP directory becomes available. For additional help downloading data through an FTP client, go to the How to access data using an FTP client support page.
Ice Thickness and Internal Layer Depth Along the 2001 and 2002 US ITASE Traverses, Version 1
Geographic Coverage
Spatial Coverage: |
|
---|---|
Spatial Resolution: | Not Specified |
Temporal Coverage: |
|
Temporal Resolution: | Not specified |
Parameter(s): |
|
Platform(s) | GROUND-BASED OBSERVATIONS |
Sensor(s): | RADAR, RADAR ECHO SOUNDERS |
Data Format(s): |
|
Version: | V1 |
Data Contributor(s): | Robert Jacobel |
Metadata XML: | View Metadata Record |
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.
Jacobel, R. and B. Welch. 2005. Ice Thickness and Internal Layer Depth Along the 2001 and 2002 US ITASE Traverses, Version 1. [Indicate subset used]. Boulder, Colorado USA. NSIDC: National Snow and Ice Data Center. doi: http://dx.doi.org/10.7265/N5R20Z9T. [Date Accessed].Detailed Data Description
Four ASCII text files contain the data. Each file has columns for longitude and latitude in decimal degrees, ice thickness in meters, and depth to the prominent internal layer in meters. Data spacing along the traverse is approximately 12 m. For each year of the traverse (2001 and 2002), an "info_table.txt
" table indicates where the core sites were located along the route as well as any turns (kinks) in the traverse.
Corresonding JPEG image files show graphical plots of the data. Each year of the traverse also has a small "data_sample.jpg
" image of radar data and two "map.jpg
" files showing maps of the routes each year.
ASCII files:jacobel_usitase_2001_01-6_ellsworth.txt
jacobel_usitase_2001_byrd_01-6.txt
jacobel_usitase_2001_info_table.txt
jacobel_usitase_2002_byrd_spole.txt
jacobel_usitase_2002_herc_dome.txt
jacobel_usitase_2002_info_table.txt
JPEG files:jacobel_usitase_2001_01-6_ellsworth_plot.jpg
jacobel_usitase_2001_byrd_01-6_plot.jpg
jacobel_usitase_2001_map.jpg
jacobel_usitase_2001_RES_data_sample.jpg
jacobel_usitase_2002_byrd_spole_plot.jpg
jacobel_usitase_2002_herc_dome_plot.jpg
jacobel_usitase_2002_map.jpg
jacobel_usitase_2002_RES_data_sample.jpg
File sizes range from 1 KB to 4 MB.
The traverses fall within the following bounding coordinates:
Southernmost Latitude: 90°S
Northernmost Latitude: 80°S
Westernmost Longitude: 120°W
Easternmost Longitude: 76°W
Spatial Coverage Map
Above is a map of the 1999-2002 traverse routes for the U.S. portion of the International Transantarctic Scientific Expedition (US ITASE).
Spatial Resolution
Data spacing along the traverse is approximately 12 m. Surface elevations along the traverse are available from a companion data set by Hamilton et al. at U. of Maine.
Data were collected from 01 November 2001 to 10 January 2003.
Unit of Measurement
Data files contain ice thickness and depth to the prominent internal layer in meters. Thickness and depth data are accurate to ± 10 m, and position values are accurate to within 1 m.
Sample Data Record
The following sample shows the first several lines of "jacobel_usitase_2001_01-6_ellsworth.txt
."
Latitude |
Longitude |
Distance-kilometers |
17.5ka bed_depth |
---|---|---|---|
-76.1011 |
-89.0138 |
0 -9999 |
2131.305 |
-76.1012 |
-89.0138 |
0.010691 -9999 |
2125.425 |
-76.1014 |
-89.0137 |
0.026805 -9999 |
2125.425 |
-76.1014 |
-89.0137 |
0.035792 -9999 |
2127.945 |
-76.1015 |
-89.0136 |
0.046494 -9999 |
2125.425 |
-76.1016 |
-89.0136 |
0.057361 -9999 |
2125.425 |
Software and Tools
Data Acquisition and Processing
A ground-based impulse radar was used to sound the ice. Approximately 1,500 traces were averaged (stacked) for each waveform and recorded at approximately 12 m intervals. Positions were acquired with a dual-frequency precision Global Positioning System (GPS) using kinematic survey mode and differential correction.
A bright, reflective layer from volcanic activity dated 17,500 years ago is visible in all of the major cores (Byrd, Siple, etc.)
Data were collected with a ground-based impulse radar with a center frequency of approximately 3 MHz.
References and Related Publications
Contacts and Acknowledgments
Robert Jacobel and Brian Welch
St. Olaf College
Department of Physics
Northfield, MN 55057 USA
This research was supported by NSF OPP award #9814574, "Radar Studies of Internal Stratigraphy and Bedrock Topography Along the US ITASE Traverse."
Document Information
DOCUMENT CREATION DATE
March 2005
Access complete Knowledge Base
Questions? Please contact:NSIDC User Services
Phone: 1 303 492-6199
Email: nsidc@nsidc.org