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Updated: Jul 30, 2026
08:16
Ice Generation and the Heat and Mass Transfer Phenomena of Introducing Water to a Cold Bath of Brine
Published on: March 13, 2017
Ice flow direction change in interior West Antarctica
Martin J Siegert1, Brian Welch, David Morse
1Centre for Polar Observation and Modelling, Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol BS8 1SS, UK. m.j.siegert@bristol.ac.uk
Science (New York, N.Y.)
|September 28, 2004
Summary
A unique ice fold near Byrd Station suggests past ice flow changes in West Antarctica. This finding indicates central West Antarctica may be more sensitive to future ice stream alterations than previously understood.
Area of Science:
- Glaciology
- Geophysics
- Antarctic Research
Background:
- Ice-penetrating radar reveals unusual fold structures beneath the West Antarctic ice sheet.
- Isochronous ice layers are found at unusually deep levels within this fold structure.
Purpose of the Study:
- Investigate the formation of a distinctive fold structure in the ice near Byrd Station.
- Reconstruct past ice flow dynamics in West Antarctica.
Main Methods:
- Analysis of ice-penetrating radar data.
- Interpretation of ice layer isochrons and fold axis orientation.
- Modeling of ice flow dynamics.
Main Results:
- A large fold structure (>50 km long) was identified, with its axis oriented up to 45 degrees to the current ice flow direction.
- The fold's formation is difficult to explain with present-day ice flow.
- A past flow regime, parallel to the fold axis approximately 1500 years ago, can explain the observed structure.
Conclusions:
- Past changes in ice flow dynamics in West Antarctica are evident from sub-ice structures.
- These flow changes may be linked to alterations in ice streams nearer the Antarctic coast.
- Central West Antarctica's ice may be more responsive to future changes than previously assumed, impacting sea-level rise projections.
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