Climate change in the upper Paraguay Basin and hydrological impacts on the Pantanal

This study analyzed the impact of climate change on the hydrological conditions of the Upper Paraguay Basin, which has as its outlet the river channel in the municipality of Cáceres – Mato Grosso, Brazil, close to the plateau/Pantanal plain divide. Using the SWAT+ hydrological model and projections from the HADGEM and MIROC models, different flow scenarios were simulated under radiative concentration thresholds (RCP) 4.5 and 8.5. The results showed an average annual reduction of 44.07% in HADGEM 4.5, 51.00% in HADGEM 8.5, 37.35% in MIROC 4.5, and 39.12% in MIROC 8.5 inflows. The results are crucial for the management of water resources, the operation of the Paraguay-Paraná Waterway, and the resilience of the ecosystem, helping decision-making and management considering the predicted climate and hydrological changes.