ABSTRACT
Environmental change, and in particular climatic change, may alter geomorphic process rates and process regimes in landscapes. These alterations may drive the landscape into disequilibrium, causing geomorphic activity to increase for a while or possibly to stop. This will be especially so with a change in process regime because the landscape will automatically be in disequilibrium with the new processes. A phase of intense activity will likely ensue, involving the reshaping of hillslopes, the reworking of regolith, and the changing of sediment stores in valley bottoms. Richard Chorley and his co-authors (1984, 1-42) claimed that geomorphologists working on Pleistocene and Holocene timescales lacked a cogent theoretical base for explaining the links between climatic forcing and geomorphic change, and adopted a rather spongy paradigm involving the concepts of thresholds, feedbacks, complex response, and episodic activity. Over twenty years later, climatic changes induced by changes in the frequency and magnitude of solar radiation receipt – orbital forcing – provide in part the missing theoretical base against which to assess the complex dynamics of landform systems: landscape changes over periods of 1,000 to 100,000 years display
consistent patterns largely forced by climatic, eustatic, or tectonic conditions. This chapter will explore landscape change during the Quaternary period, focusing on fluvial, aeolian, marine, and hillslope environments.
