Im. Whillans et Cj. Vanderveen, NEW AND IMPROVED DETERMINATIONS OF VELOCITY OF ICE STREAM-B AND ICE STREAM-C, WEST ANTARCTICA, Journal of Glaciology, 39(133), 1993, pp. 483-490
Measurements of velocity have been made on and next to Ice Streams B a
nd C, West Antarctica. The results are more precise than previous work
and constitute a 93% increase in the number of values. These velociti
es are used to describe the confluence of flow into the ice streams an
d the development of fast ice-stream flow. The onset of fast-streaming
flow occurs in many separate tributaries that coalesce down-glacier i
nto the major ice streams. For those inter-stream ridges that have bee
n studied, the flow is consistent with steady state. Along Ice Stream
B, gradients in longitudinal stress offer little resistance to the ice
flow. The transition from basal-drag control to ice-shelf flow is ach
ieved through reduced drag at the glacier base and increased resistanc
e associated with lateral drag. Velocities in the trunk of Ice Stream
C are nearly zero but those at the up-glacial head are similar to thos
e at the head of Ice Stream B.