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Antarctic Ice Velocity Data
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The above overview map is a subscene from the USGS 1-km AVHRR mosaic (Ferrigno et al., 1996). To view image data select Velocity Map, or use the link on the overview image.
Excerpts taken from Whillans and Van Der Veen, 1993 (see Related Publications)
Poles were placed vertically in the surface of the ice sheet and surveyed on at least two occasions for position. The base map for Figure 2 includes the major geographic features mapped from aerial photographs and satellite imagery. Figure 3 shows velocity vectors together with elevation contours and the boundaries to the ice streams.
The surveying was done using Transit (also called "Doppler") satellite receivers. Most of the equipment were Magnavox model 1502 "Geoceivers", which were left tracking at each site for about 24 hours. The data are educed using precise, post-processed orbits for the satellites, or else they are linked in a network adjustment to other sites with positions so obtained. Absolute positions of the survey stations are accurate to about 1 m. Relative positions for stations linked together in a network adjustment are more precise, but discussion here relates to absolute velocities, which are accurate to 0.4 m/a.
Data Set Sources: (See Related Publications)
Whillans, I.M. and C.J. Van Der Veen. 1993. New and improved determinations of velocity of Ice Streams B and C, West Antarctica. Journal of Glaciology, Vol. 39, No. 133, 483-490.
Whillans, I.M., J. Bolzan and S. Shabtaie. 1987. Velocity of Ice Streams B and C, Antarctica. Journal of Geophysical Research, 92(B9), 8895-8902.
Access the tabular velocity data for Ice Stream B
