Desert Environment

Abstract

Desert climates are characterised in detail: average annual rainfall ranges from essentially zero (South American coastal deserts, Libyan deserts, etc) to c600 mm (Madagascar), and fog and dew may provide moisture in some regions; all hot deserts have absolute maximum temperatures of 40oC and above (more usually 45-47oC), but mean temperatures vary for different hot desert types; radiation is very intense throughout the year; the range of evaporation from a 'Class A' evaporation pan is 2000-4000 mm yr"SUP -1" for hot deserts, except for humid coastal deserts which have lower values. Climatic trends during the Pleistocene and Holocene are indicated. The nature of landscapes and landforms is outlined and aspects of geology, soils (mainly Entisols and Aridisols, with some Vertisols and Alfisols) and hydrology are also described. -P.J.Jarvis