Comparative Analysis of Drought Indices in Hydrological Monitoring in Ceará’s Semi-Arid Basins, Brazil

The purpose of this work is to evaluate the applicability five drought indices (Surface Water Supply Index—SWSI, Reclamation Drought Index—RDI, Streamflow Index—SDI, Standardized Precipitation Index—SPI, and Evaporative Demand Index—EDDI) as tools for monitoring, in identifying duration, intensity, frequency hydrological droughts basins Banabuiú, Castanhão, Orós reservoirs, located state Ceará, Brazil. analysis focused on determining performance indexes capturing characteristics from 2002 2020. Thus, comparison values with Target Levels reservoir’s operation were used, well six decision criteria: robustness, tractability, transparency, sophistication, extensibility, dimensionality, compare behavior indices. results evaluation criteria showed that SPI was superior other indices, being able significantly represent episodes, a greater number events. received highest total weighted score (118), followed by SWSI (97), EDDI (95), SDI RDI (88). In context, it found are most suitable monitor region use longer time scales can be recommended manage droughts, order improve planning management water resources.