The association of landform types with different climates, such as the evolution of periglacial landforms in tundra climates. However, the geomorphic response to climatic changes, fluctuations, and episodes varies spatially and temporally. Some recent landforms result from the long-term and essentially continuous activity of particular processes. Others are surface manifestations of processes that hitherto were active but cryptic and yet others result from the impact of storm or catastrophic events, frequently, though not in every instance, on surfaces previously rendered vulnerable. ‘Few, if any, minor landforms can be accepted without question as indicators of climatic change or fluctuation’ (Twidale (1997) Geomorph. 19). See J. Büdel (1982), M. Gutierrez Elorza (2005), and Gunnell (2000) Geomorph. 35, 1–2.