Uncertainty assessment is crucial for rainfall-runoff simulations in a typical watershed. Generally, three major sources of uncertainty are input forcing, model structure, and model parameterization. The uncertainty of hydrological modelling may become more evident when it estimates unseen conditions. For instance, when studying climate change impacts, using climate projections as input for hydrological modelling brings about an inevitable uncertainty in streamflow predictions. This study aims to investigate the uncertainty of future streamflow using a semi-distributed hydrological model in the Reno basin, Italy.

