Alpine and Polar Periglacial Processes: The Current State of KnowledgeOle Humlum Abstract Recently the traditional view on the geomorphological evolution
of periglacial landscapes has been questioned. The geomorphological
processes considered most important for landscapes in periglacial
regions, in general, are not unique for periglacial environments.
On the other hand, there is a suite of geomorphological processes
which may be seen as characteristic for periglacial environments.
Based on what the author considers characteristic periglacial phenomena
and landforms, this paper attempts to identify what might be conceived
as the main characteristic periglacial processes. Seasonal or perennial
freezing and conspicuous landforms such as extensive talus sheets,
polygonal networks, and large-scale patterned ground, dominate descriptions
of periglacial regions. Phenomena controlling bedrock disintegration,
rockfall, thermal contraction cracking, and sorting of sediments
are therefore all seen as the means to identify characteristic periglacial
processes. Each of these periglacial processes is shortly described,
and the present state of knowledge, or the lack of such, is outlined.
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