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Periglacial processes and environments |
Laboratory of Physical and Environmental Geography, GEOLAB-UMR 6042 CNRS, Blaise Pascal University, MSH – 4 rue Ledru, 63057 Clermont-Ferrand, Cedex 1, France (e-mail: m-francoise.andre{at}univ-bpclermont.fr)
Periglacial geomorphology developed in the 1940s–1960s as a branch of climatic geomorphology, focusing first on Quaternary studies and palaeoenvironmental reconstructions, then on current geomorphic activity in cold regions. The ‘periglacial fever’ of the 1960s–1970s was dominated by the ‘freeze–thaw dogma’: periglacial areas were regarded as necessarily submitted to efficient frost-driven processes ruling over the geomorphic activity. Such a view was severely criticized in the 1980s–1990s based both on monitoring studies and on time–space multiscale approaches that pointed to the need to cross the ‘smokescreen of the periglacial scenery’ to search for the real past and present processes responsible for the landform geometry. The role of non-cold-related processes in the making of ‘periglacial’ landcapes was re-evaluated, and the necessity to better take into account the rock properties and the pre-Quaternary history of slope systems was emphasized. Whereas the part of the cold-related processes was being minimized, the interest of genuine periglacial landforms as geoindicators of climate change was growing, providing a new legitimacy to periglacial geomorphology. Polar and Alpine regions are nowadays considered as key observatories of ongoing climate change, and periglacial geomorphologists are involved in the detection, monitoring and prediction of environmental changes. Finally, the evolution of ‘periglacial geomorphology’ over the past six decades is in accordance with the development of the whole geomorphology. Based on the quantitative and technological revolution, it tends to find a balance between the functional and historical approaches.
