New and improved determinations of velocity of Ice Streams B and C, West Antarctica

Measurements of velocity have been made on and next to Ice Streams B and C, West Antarctica. The results are more precise than previous work and constitute a 93% increase in the number of values. These velocities are used to describe the confluence of flow into the ice streams and the development of fast ice- stream flow. The onset of fast-streaming flow occurs in many separate tributaries that coalesce down-glacier into the major ice streams. For those inter-stream ridges that have been 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 achieved through reduced drag at the glacier base and increased resistance 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 those at the head of Ice Stream B.

[1]  R. Armstrong,et al.  The Physics of Glaciers , 1981 .

[2]  R. Frolich,et al.  Relative Importance of Lateral and Vertical Shear on Rutford Ice Stream, Antarctica , 1988, Annals of Glaciology.

[3]  R. Bindschadler,et al.  Observed velocity fluctuations on a major Antarctic ice stream , 1988, Nature.

[4]  C. Veen,et al.  Force Budget: I. Theory and Numerical Methods , 1989, Journal of Glaciology.

[5]  Ice-thickness Patterns and the Dynamics of the Ross Ice Shelf, Antarctica , 1979 .

[6]  P. Vornberger,et al.  Surface Features of Ice Stream B, Marie Byrd Land, West Antarctica , 1986, Annals of Glaciology.

[7]  D. Macayeal,et al.  Derived Characteristics of the Ross Ice Shelf, Antarctica , 1982 .

[8]  Y. Tseng,et al.  Velocity pattern in a transect across Ice Stream B, Antarctica , 1993 .

[9]  C. Bentley,et al.  Ice-Thickness Map of the West Antarctic Ice Streams by Radar Sounding , 1988, Annals of Glaciology.

[10]  D. Macayeal,et al.  Derived Characteristics of the Ross Ice Shelf, Antarctica (Abstract only) , 1982 .

[11]  D. Macayeal,et al.  Distribution of Net Mass Balance in the Vicinity of Crary Ice Rise, Antarctica , 1989, Journal of Glaciology.

[12]  R. Alley,et al.  Changes in the West Antarctic Ice Sheet , 1991, Science.

[13]  C. Bentley.  Antarctic ice streams: a review , 1987 .

[14]  S. Shabtaie,et al.  Velocity of ice streams B and C, Antarctica , 1987 .

[15]  C. Merry,et al.  Ice-flow features on Ice Stream B, Antarctica, revealed by SPOT HRV imagery , 1993, Journal of Glaciology.

[16]  Charles R. Bentley,et al.  The morphology of ice streams A, B, and C, west Antarctica, and their environs , 1987 .

[17]  V. Veen,et al.  Patterns of calculated basal drag on ice streams B and C, Antarctica , 1993, Journal of Glaciology.

[18]  Crevasse deformation and examples from ice stream B, Antarctica , 1990 .

[19]  Douglas R. Macayeal,et al.  Large‐scale ice flow over a viscous basal sediment: Theory and application to ice stream B, Antarctica , 1989 .

[20]  I. Whillans,et al.  Comparison of Results From Transit Satellite Tracking , 1988, Annals of Glaciology.

[21]  K. E. Rose,et al.  Characteristics of Ice Flow in Marie Byrd Land, Antarctica , 1979, Journal of Glaciology.

[22]  Robert Bindschadler,et al.  Force, mass, and energy budgets of the Crary Ice Rise complex, Antarctica , 1987 .

[23]  W. Harrison,et al.  Surficial glaciology of Jakobshavns Isbræ, West Greenland: Part I. Surface morphology , 1991 .

[24]  J. Turner,et al.  Dynamics of the Ross Ice Shelf , 1991 .

[25]  D. Macayeal,et al.  Mass-balance studies of ice streams A, B, and C, west Antarctica, and possible surging behavior of ice stream B , 1988 .

[26]  Roger LeB. Hooke,et al.  Flow law for polycrystalline ice in glaciers: Comparison of theoretical predictions, laboratory data, and field measurements , 1981 .

[27]  J. Turner,et al.  Relict flow stripes on the Ross Ice Shelf , 1991, Annals of Glaciology.

[28]  Charles R. Bentley,et al.  Airborne-radar studies: Ice Streams A, B and C, West Antarctica , 1993 .

[29]  Richard H. Rapp,et al.  The Ohio State 1991 geopotential and sea surface topography harmonic coefficient models , 1991 .