Climatic geomorphology?

• Main Author: Twidale, C.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Japanese Geomorphological Union 2010
• Subjects: Subarctic
• Online Access: http://hdl.handle.net/2440/63500

Climate has long been entertained as a central control of landform. Morphogenetic regions, each with its particular assemblage of forms, have been identified, including those shaped by glaciers in high latitudes and altitudes, by freeze-thaw in subarctic conditions, and by the wind in the mid-latitude deserts. So distinctive are assemblages associated with climatic extremes that climatic change can be identified where they persist in what are anomalous climatic conditions, as well as in the stratigraphic record. Yet these apart, and despite variations in climate, from humid to semiarid, and cool to hot, similar suites of forms are characteristic of the continental areas. This is partly because geological structures are climatically azonal. Fault scarps, volcanoes, ridge-and-valley topography typical of dissected fold mountains, landforms associated with particular rock types such as limestone, granite and sandstone are found in various climatic settings. Rivers and associated forms dominate landscapes in the humid tropics, temperate lands, the savannas and even the hot desert lands. Many familiar landforms are shaped not at the land surface, and by the processes active there, but at the base of the regolith. They are later exposed by the stripping of the soil cover. Shallow groundwaters are ubiquitous and so are such etch or two-stage forms. They are modified after exposure but in many instances retain their basic form. The distribution of high energy or storm events (e.g. floods) is also independent of climate as are forms such as gullies caused by various human activities. C. R. Twidale