Content area
The present investigation was primarily aimed at cross-comparing the agricultural drought declaration potential of a 4-month averaged Composite Drought Index (CDIavg) vs. its end of the season monthly (i.e. CDIsep) values over one of the most drought-prone states (i.e. Karnataka) of India. The afore-stated composite drought indices were based on a combination of three indicators, namely Standardized Precipitation Index (SPI), Evaporative Stress Index (ESI) and Normalized Difference Vegetation Index anomaly (NDVIanamoly). Because kharif season (June to September) is considered to be one of the most important seasons for farming in India, the drought declaration potential of the developed composite drought indices (i.e., CDIavg and CDIsep) was evaluated in terms of their cross-comparison with the government declared droughts and crop yield anamolies during 18 - kharif cropping seasons of the validation years from 2001 to 2018. The investigation revealed superior performance of the (objective and spatially distributed) composite drought index-based approaches over the conventional (subjective and lumped) drought declaration protocols being followed by the state and the central governments. Amongst the proposed two composite drought index-based approaches, the end of the season composite drought index (i.e., CDIsep) based protocol was observed to be comparatively more precise in targeting varied category drought hit areas. The investigation thus demonstrated immense potential of the validated approach for rational allocation of government relief funds, in proportion to the intensity and extent of droughts, across the study area.