Spatiotemporal assessment of drought hazard, vulnerability and risk in the Krishna River basin, India

Spatial and temporal assessment of drought hazard over the Krishna River basin of India has been performed using long-term (January 1901–December 2002) precipitation and temperature data. Various meteorological drought indices such as the Standardized Precipitation Index, Standardized Precipitation Evapotranspiration Index, Standardized Effective Precipitation Evapotranspiration Index and Reconnaissance Drought Index (RDI) have been evaluated on a 12-month timescale for assessment of the drought hazard. Various physical drought characteristics such as the maximum drought magnitude, maximum drought duration and probability of occurrence of droughts, i.e., drought frequency, are also analyzed for the Krishna River basin. Analysis led to identification of major dry periods from the evaluated drought characteristics and generation of spatial maps of magnitude, duration and intensity for each index for each of the dry periods. The socioeconomic aspects of drought have also been explored by analyzing drought hazard, vulnerability and risk which are mapped spatially to evaluate drought susceptibility of various regions in the basin. The study revealed a positive correlation between the maximum drought magnitude, drought duration and drought risk, and an indirect proportionality between drought intensities and drought frequency. The analysis of physical drought characteristics revealed that the RDI deviated significantly from the remainder indices. The importance of socioeconomic variables is also highlighted as districts having normal meteorological conditions became the hotspots of drought risk because of sensitive demographics in the study basin.