CA, 9-11 Nov. 1999 
growing bulge will determine 
id will illustrate the effect of 
bly the advancement of a 
a major change of the studied 
  
Bed elevation 
...(m.a.s.l.) 
-400m 
  
  
  
Em -580 -560 
(km) 
itours (blue) of the surface of Ice 
ations from airborne radar surveys 
ed arrows show ice flow direction 
ns and Van der Veen, 1993, and 
ow diamond is a coffee-can site 
validate laser derived elevations 
slack line shows the track of the 
JUSIONS 
/as expected that uncertainties 
The large uncertainties were 
S solutions because the GPS 
are at low angles making it 
ertical. Uncertainties in the 10 
und instead. Most elevations 
are within 20 cm during the 
cm for crosses involving two 
| of precision is acceptable, but 
with better GPS surveying 
ide static initialization at the 
y, beginning and ending flights 
ore surveys conducted on the 
on. Nevertheless, this level of 
n ice sheet elevations to be 
al for most of the study region. 
0 be a valuable tool for mass 
Antarctica. It is also shown to 
sual topographic features that 
ig of glacier mechanics. 
   
International Archives of Photogrammetry and Remote Sensing, Vol. 32, Part 3W14, La Jolla, CA, 9-11 Nov. 1999 
ACKNOWLEDGEMENTS 
We would like to thank John Sonntag for helping validate our 
GPS surveys, Dorota Grejner-Brzezinska for helping in 
processing the GPS data, and SOAR for acquiring the laser data 
and helping with processing concerns. Funding for this project 
is provided by National Science Foundation grant OPP- 
9615114. 
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