Drought severity assessments for mitigation and management of drought prone area

Abstract

Drought is an insidious natural hazard that usually results from lower levels of precipitation, than what is considered to be normal. When this phenomenon extends over a season or a longer period, the precipitation is insufficient to meet the demands of human activities and the environment. The National Commission on Agriculture (1976), broadly classified drought into Meteorological drought, Hydrological drought, and Agricultural drought, whose severity and duration can be determined using a drought index, which is typically a single number, far more useful than raw data for decision making. Drought is a stochastic natural hazard that is instigated by an intense and persistent shortage of precipitation. Following an initial meteorological phenomenon, subsequent impacts are realized on agriculture and hydrology. Among the natural hazards, droughts possess certain unique features; in addition to delayed effects, droughts vary by multiple dynamic dimensions including severity and duration. Droughts are a cyclical and regional natural climatic phenomenon. Drought may be defined as any unusual dry period, which results in a shortage of water. Precipitation deficiencies, due to natural climatic variability in space and time, are therefore the primary cause of droughts. Among all other natural disasters, the drought affects the maximum number of people in the world and more so in India. Though drought cannot be prevented, being well prepared for its likely occurrence can lessen its impacts on life and plants. To manage drought, drought characterization is essential enabling both retrospective analyses (e.g., severity versus impacts analysis) and prospective planning (e.g., risk assessment). The adaptation of a simplified method by drought indices has facilitated drought characterization for various users and entities. Hence, proper knowledge and understanding of iv this inevitable natural hazard are very essential for the management and planning before or during a drought. newline