Geophysical Research Letters 38 (2011) L24501; doi:10.1029/2011GL049970
Traveling supraglacial lakes on George VI Ice Shelf, Antarctica
Abstract
We describe a sequence of supraglacial lakes on
the George VI Ice Shelf, Antarctica, that migrate along the boundary of
the
ice shelf with Alexander Island in the manner of
a traveling wave, with a velocity that differs from the local ice-shelf
flow
in both magnitude and direction. These lakes are
arranged en échelon along a grounding line of the ice shelf
where the flow displays the atypical feature of being directed toward
land. A simple
model presented here suggests that the
propagating lakes form in the depressions of a viscous-buckling wave
associated with
compressive ice-shelf stresses and ice-flow
directed obliquely toward the coastline. The existence of these lakes
and their
propagation gives rise to the implication that
other ice-shelf surface features (e.g., patterns of swells and
depressions,
surface lakes, and drainage) can be organized by
large-scale viscous buckling behavior, when ice-shelf flow is strongly
compressive.
Received 11
October
2011;
accepted 17
November
2011;
published 28
December
2011.
Key points:
- We discover a type of supraglacial lake that propagates as a wave
- These waves result from large-scale stress regime
- Thus, large-scale stress regime may determine how lakes mediate shelf stability
Citation:
(2011). Traveling supraglacial lakes on George VI Ice Shelf, Antarctica,
Geophys. Res. Lett.,
38,
L24501,
doi:10.1029/2011GL049970.
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