GEOG 106 Lecture Notes - Lecture 11: Semi-Arid Climate
Document Summary
Half of the dry land is true desert. Sustained use of agriculture and settlements in these areas is very limited. Where possible, groundwater or exotic streams which flow into the desert from wetter climates must be utilized. Bordering the deserts are the semiarid lands or steppe: Drought is usually relatively mild or absent for part of the year o usually. Sustained agriculture and settlement are possible there assistance of irrigation. Prior to 20th century these areas were the world"s greatest grazing lands, now grasslands (modern times) it is used for croplands, particularly wheat farming. In the tropics the tropical wet/dry lands have a short wet season in the summer with dry conditions the rest of the year tropical savannah land. An important factor in understanding the dry lands as frontier environment is moisture variability over time. Variability is a measure of precipitation dependability how steady the annual moisture supply is from year to year.
