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Data Set ID:

Whillans Ice Stream Stick-slip, Version 1

These data contain ice velocity measurements obtained from seismic and GPS recordings during the 2010 and 2011 Antarctic field seasons.

Geographic Coverage

  • Glaciers/Ice Sheets > Glacier Motion/Ice Sheet Motion
  • Seismology > Seismic Surface Waves
Spatial Coverage:
  • N: -83.75, S: -84.75, E: -155, W: -165

Spatial Resolution: Not Specified
Temporal Coverage:
  • 1 November 2010 to 31 December 2011
Temporal Resolution: 00:00:15, 00:03:20 to 00:08:20
Data Format(s):
Version: V1
Data Contributor(s): Paul Winberry, Sridhar Anandakrishnan, Doug Wiens, Richard Alley
Please contact the data provider for the correct Data Citation for this data set.

Literature Citation

As a condition of using these data, we request that you acknowledge the author(s) of this data set by referencing the following peer-reviewed publication.

  • Pratt, M. J. et al. 2014. Evidence for Grounding Line Control of Whillans Ice Stream Stick–Slip Events from Seismic and Geodetic Observations, Journal of Geophysical Research - Earth Surface. 119. 333-348.

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Detailed Data Description

These data contain ice velocity measurements obtained from seismic and GPS recordings during the 2010 and 2011 Antarctic field seasons. The data are the processed GPS data of ice velocity movement from the 2010 and 2011 Antarctic field seasons. The raw seismic data for the same period are available on the IRIS DMC MetaData Aggregator site, and the raw GPS data can be found on the UNAVCO site. See Data Access for links.

Sensor Locations
Figure 1. a. Location of GPS Sensors b. Seismic Station Coverage

Processed GPS data are provided in MATrix LABoratory (MATLAB) (.mat) format.

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File and Directory Structure

The processed GPS data are available on the FTP site in the directory. This directory contains two files: WIS10.mat ( 2010 data) and WIS11.mat ( 2011 data).

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File Naming Convention

The file naming convention used for the two MATLAB (.mat) files in this data set is described in Table 1.

Table 1. File Naming Convention
Variable Description
WIS Whillans Ice Sheet
## Year data were collected
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File Size

WIS10.mat is 71.9 MB
WIS11.mat is 17.3 MB

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The data set is 89.2 MB.

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Spatial Coverage

Southernmost Latitude: 84.75° S
Northernmost Latitude: 83.75° S
Westernmost Longitude: 165° W
Easternmost Longitude: 155° W

Spatial Resolution

Spatial resolution varies.

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Temporal Coverage

Data were collected from 1 Nov 2010 to 31 Dec 2011.

Temporal Resolution

GPS measurements were taken every 15 seconds.
The temporal resolution for the seismic readings ranges between 200-500 Hz (one cycle per second).

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Parameter or Variable

Ice Sheet Motion (m)
Seismic Sound Waves (m)

Sample Data Record

Each file contains seven fields. Refer to Table 2 for an explanation of the fields and Figure 2 for an example of the list.

Table 2. Fields List
Field Description
t Vector containing time (day of year), same length as n, e, and z fields
x vector conting "x" location of stations (Polar stereographic x in kilometers)
y vector containing "y" location of stations (Polar stereographic y in kilometers)
e matrix containing relative "east" displacement (m), one column per station
n matrix containing relative "north" displacement (m), one column per station
z matrix containing relative vertical displacement (m), one columne per station
file directory
Figure 2. MATLAB file directory

Refer to Figure 3 for an example of one of the data fields. The sample data are from the "e" field, showing the first seven stations' eastern displacement. When no data is available, the value equals Not a Number (NaN).

Sample data
Figure 3. Sample Data
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Software and Tools

The processed GPS files can be accessed using MATLAB software.

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Data Acquisition and Processing

Data Acquisition Methods

GPS data were collected with geodetic quality instruments provided by the UNAVCO instrument center, and the seismic data were collected with broadband seismic instruments provided by the IRIS PASSCAL instrument center.

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Derivation Techniques and Algorithms

Processing Steps

Processed GPS data were produced with the Track Software Package relative to the base station RAMG (Ramsey Glacier Station)

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References and Related Publications

Contacts and Acknowledgments

Paul Winberry
Central Washington University
Department of Geological Sciences
400 E. University Way, MS 7418
Ellensberg, WA 98926 United States

Sridhar Anandakrishnan
Penn State 
Department of Geosciences
0442 Deike Building University Park
University Park, PA 16802 United States

Doug Wiens
Washington University in St. Louis
Department of Earth and Planetary Sciences
Campus Box 1169
1 Brookings Dr.
Saint Louis, MO 63130 United States

Richard Alley
Penn State
Department of Geosciences
517B Deike Building University Park
University Park, PA 16802 United States


This research was funded by National Science Foundation (NSF) grant number 0944794.

Document Information


29 July 2014

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