Climate extremes and socioeconomic impacts of extreme rainfall events in April and May 2024 in Rio Grande do Sul, Brazil

This study evaluates observed changes in temperature and precipitation extremes across the state and examines the May 2024 floods as a case study of evolving risk conditions in southern Brazil. Extreme flooding in Rio Grande do Sul has intensified concern about how climate change is influencing hydroclimatic hazards and reinforcing unequal impacts across urban systems.

The results indicate regionally consistent warming, increasing intensity of precipitation extremes, and amplified rainfall variability across multiple subregions. In this context, the 2024 floods are consistent with a higher probability of high-impact events under a warmer climate. In Porto Alegre, the most affected areas coincide with sectors where elevated surface-water presence intersects with high population density and infrastructural fragility, demonstrating a clear spatial overlap between environmental exposure and socioeconomic vulnerability. The event also underscores the linkage between climate extremes and public health, as flood-related disruptions to essential services increased health risks in densely inhabited areas.