EVOLVING DROUGHT TYPES IN THE CUBATÃO RIVER BASIN, BRAZIL

Código

XXVI-SBRH0325

Autores

VIRGÍNIA GRACE BARROS, Jean Pierre Henry Balbaud Ometto, Therezinha Maria Novais de Oliveira, Leonardo Romero Monteiro, Jessica Carolina dos Santos Silva, Franciele Maria Vanelli, Lira Luz Benites Lazaro, ELISA HENNING

Tema

A - Planejamento e Gestão de Recursos Hídricos e Segurança Hídrica

Resumo

This study examines drought dynamics and water availability in the Cubatão Watershed (Santa Catarina, Brazil), mean rainfall 2100mm, integrating hydroclimatic data analysis with machine learning-based forecasting. A hydrological balance was constructed using WEAP, incorporating precipitation, potential evapotranspiration (PET), and observed streamflow data to compute total water availability (Q_tot). The Standardized Precipitation-Evapotranspiration Index (SPEI) was calculated at 1-month and 3-month timescales using the SPEI R package, allowing for the historical assessment of drought severity and frequency based on observed data series, as well as projections under the SSP2 and SSP5 scenarios. To assess long-term trends, spatial averages of SPEI1 and SPEI3 were computed for each 5-year interval. Under historical conditions, results reveal occurrence of negative SPEI anomalies between July and October, indicating seasonal susceptibility to water deficits. For SSP2 and SSP5 projections droughts events tend to be intensified and prolonged.