It has been conjectured that marine ice sheets (those that
flow into the ocean) are unconditionally unstable when the underlying
bed-slope runs uphill in the direction of flow, as is typical in many
regions underneath the West Antarctic Ice Sheet. This conjecture is
supported by theoretical studies that assume a two-dimensional flow
idealization. However, if the floating section (the ice shelf) is
subject to three-dimensional stresses from the edges of the embayments
into which they flow, as is typical of many ice shelves in Antarctica,
then the ice shelf creates a buttress that supports the ice sheet.
This allows the ice sheet to remain stable under conditions that may
otherwise result in collapse of the ice sheet. This talk presents new
theoretical and experimental results relating to the effects of
three-dimensional stresses on the flow and structure of ice shelves,
and their potential to stabilize marine ice sheets.
- Mathematical Geoscience Seminar