Ice‐shelf basal channels form due to concentrated submarine melting. They are present in many Antarctic ice shelves and can reduce ice‐shelf structural integrity, potentially destabilizing ice shelves by full‐depth incision. Here, we describe the viscous ice response to a basal channel—secondary flow—which acts perpendicular to the channel axis and is induced by gradients in ice thickness. We use a full‐Stokes ice‐flow model to systematically assess the transient evolution of a basal channel in the presence of melting. Secondary flow increases with channel size and reduces the rate of channel incision, such that linear extrapolation or the Shallow‐Shelf Approximation cannot project future channel evolution. For thick ice shelves (
- PAR ID:
- 10322206
- Date Published:
- Journal Name:
- Journal of Glaciology
- Volume:
- 67
- Issue:
- 265
- ISSN:
- 0022-1430
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1017/jog.2021.39
