River discharge in South America : agreement and contradictions between recent alteration and projected changes

• Published in: RBRH
• Main Authors: Miranda, Pedro Torres, de Paiva, Rodrigo Cauduro Dias, de Araújo Gama, Cléber Henrique, Brêda, João Paulo Lyra Fialho
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2023
• Subjects: Climate change impacts; Discharge alteration; Robustness; South America; Northeast Atlantic
• Online Access: https://research.wur.nl/en/publications/river-discharge-in-south-america-agreement-and-contradictions-bet; https://doi.org/10.1590/2318-0331.282320220085

Climate scenarios are important information for water planning, but, in some cases, they disagree with recent climate alterations, which affects their robustness and reliability. Robustness evaluation can help identifying areas that should be prioritized by in water sector adaptation to climate change. Although crucial, this kind of analysis has been overlooked in most climate change assessments, for instance in South America. This study assesses the robustness and reliability of river discharge scenarios by comparing them with observed and modelled data. Areas where current changes and scenarios agree are more likely to experience changes and, therefore, water planners should pay special attention to them. Tocantins-Araguaia, São Francisco, Western Northeast Atlantic and upper La Plata basins agreed with a discharge decrease, indicating that climate change should be prioritized in planning. Orinoco and upper-western Amazon basins showed strong disagreement between recent and projected discharge alterations, with positive change in last decades, showing that scenarios in these regions should be carefully interpreted. With this, water planners could interpret Northeastern and upper-central South America as presenting more likely scenarios in comparison to Amazon and Orinoco basins.