Assessment of Meteorological Drought Indices for Monitoring Drought Condition in the Sone Command Area, Bihar, India- A case study

Abstract

Drought is a hazard that affects most settled areas occasionally or periodically. Drought is a common natural disaster in India. In India, more than 70 percent of people, primarily depend on agriculture. In the present study, average monthly rainfall data from 1901 to 2002 were analyzed to determine monthly and yearly metrological drought occurrence in the Sone command area of the state of Bihar, India. The average rainfall of the Sone command area is 1100 mm, seven different metrological drought indices, namely IMD method, Decile index, standard precipitation index, reconnaissance drought index, Percent of normal, Aridity index, and moisture adequacy index were selected mainly reflecting metrological droughts. Also, an effort has been made to find out the districts facing the most severe drought conditions. As per the results, the most common kind of SPI was normal to moderately dry and that of IMD Method was moderate drought condition. Index of Aridity and percent of the normal index did not show good results for the drought severity as they have predicted most of the months to have no drought condition. The moisture adequacy index shows disastrous drought every year. RDI and SPI index show the same results. The drought has been monitored by the use of several meteorological indices, and it is clear that the present study area is experiencing normal to moderate drought.