Advances in Permafrost and Periglacial Research in the Dry Valleys, AntarcticaBernard Hallet, Ronald S. Sletten, Jaakko Putkonen Abstract Extremely dry and cold conditions in continental portions of Antarctica
lead to permafrost properties and periglacial processes that merit
special attention because they are quite distinct from those in
the Arctic, which are generally more familiar. Moreover, they resemble
most closely those on Mars, providing powerful analogues that are
helpful in interpreting the surface of the planet and the dominant
surficial processes, as well as evidence for major recent change
in the climate of Mars. Herein, we review recent studies of periglacial
processes and implications for understanding the hyper-arid, cryogenic
landscape typical of the non-ice covered portions of the Antarctic
continent and beyond. Our review is selective as it is limited to
the research we are familiar with in the Dry Valleys region; it
includes 1) thermal and moisture states of Antarctic permafrost
2) factors affecting the formation, stability and longevity of ice
below the ground surface, 3) nature and rates of patterned ground
processes with a focus on sand-wedge polygons, 4) rates and mechanisms
of permafrost creep, hillslope processes and sediment transport,
and 5) specific analogues pertinent to permafrost and periglacial
activity on Mars, and related inferences about Martian climate change. |
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