Drought And Its Effects On Drought Essay

820 Words Oct 18th, 2015 4 Pages
Introduction
Risk associated with drought requires information from drought monitoring system as the monitoring system provide onset, progress, severity and spatial extent of drought. Such information, when available, assists in drought contingency plans. Drought monitoring is normally performed using drought indices that are continuous function of precipitation and other meteorological variables (Younes et al., 2011). Drought is considered as one of the most complex and least understood of all natural hazard. Due to large scale spatiotemporal variability in timing and duration of drought impact, it is hard to find the definition of drought that fits for all circumstances because drought is not an absolute physical phenomenon that is only characterized by the climate. However, in any circumstances both demand and supply of water are essential to define drought as Redmond (2002) define drought as “insufficient water to meet needs”. Whenever human demands for water surpass the characteristic accessibility of water, the result is a dry season. According to International Strategy for Disaster Reduction (ISDR) (2004) drought can be classified into three categories: 1) Meteorological (insufficient precipitation, mostly rainfall 2) Hydrological (drying of surface water storage), and 3) Agricultural (lack of root zone soil moisture).
Many indices under different types of drought have been developed in the past. These include the Palmer Drought Severity Index (PDSI) (Palmer, 1965),…

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