Comparison of two hydrological drought indices
详细信息   
摘要
Drought is a naturally occurring periodical event associated with significant decrease of water availability over a region. Drought, being a complex in nature it is difficult to define, quantify and monitor. Drought is mainly classified into meteorological drought, hydrological drought and agricultural drought. Among these classifications, assessment of hydrological drought has more importance in the water resources management perspective. Objective of this study is to analyse multi-time step hydrological drought by Stream flow Drought Index (SDI) and Standardized Runoff Index (SRI). To obtain these indices, 36 years (1972–2007) of daily discharge data, measured in Ghataprabha river basin (a sub basin of Krishna river) is considered. Results of both indices indicate moderate drought between 1986–1988 and 2001–2005 continuously. While comparing both indices, there is a good correlation between 9-month SRI and SDI is observed and it increases for 12-month SRI and SDI. This study may help to choose the appropriate drought indices among SRI and SDI for different lengths of drought studies.