Page 294 - Fundamentals of Geomorphology
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                              PERIGLACIAL LANDSCAPES




















              Frozen ground without an icy cover bears an assortment of odd landforms. This chapter covers:


                  ice in frosty landscapes
                  frost, snow, water, and wind action
                  pingos, palsas, and other periglacial landforms
                  humans in periglacial environments

              A window on the periglacial world

              In 1928, the airship Graf Zeppelin flew over the Arctic to reveal:
                the truly bizarre landscape of the polar world. In some areas there were flat plains stretching from horizon to horizon that were dotted
                with innumerable and inexplicable lakes. In other regions, linear gashes up to a mile or more long intersected to form giant polygonal
                networks. This bird’s-eye view confirmed what were then only incidental surface impressions that unglaciated polar environments were
                very unusual.
                                                                                     (Butzer 1976, 336)




              PERIGLACIAL ENVIRONMENTS                  Stockholm to describe climatic and geomorphic condi-
                                                        tions in areas peripheral to Pleistocene ice sheets and
              The term ‘periglacial’ was first used by Polish geomor-  glaciers. This periglacial zone covered tundra regions,
              phologist Walery von Lozinzki in 1909 to describe frost  extending as far south as the latitudinal tree-line. In mod-
              weathering conditions in the Carpathian Mountains of  ern usage, periglacial refers to a wider range of cold but
              Central Europe. In 1910, the idea of a ‘periglacial zone’  non-glacial conditions, regardless of their proximity to a
              was established at the Eleventh Geological Congress in  glacier. It includes regions at high latitudes and below
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