Hydrological Modeling Response to Climate Model Spatial Analysis of a South Eastern Europe International Basin

One of the most common questions in hydrological modeling addresses the issue of input data resolution. Is the spatial analysis of the meteorological/climatological data adequate to ensure the description of simulated phenomena, e.g., the discharges in rainfall-runoff models at the river basin scale, to a sufficient degree? The aim of the proposed research was to answer this specific question by investigating the response of a spatially distributed hydrological model to climatic inputs of various spatial resolution. In particular, ERA-Interim gridded precipitation and temperature datasets of low, medium, and high resolution, i.e., 0.50 degrees x 0.50 degrees, 0.25 degrees x 0.25 degrees, and 0.125 degrees x 0.125 degrees, respectively, were used to feed a distributed hydrological model that was applied to a transboundary river basin in the Balkan Peninsula, while all the other model's parameters were maintained the same at each simulation run. The outputs demonstrate that, for the extent of the specific basin study, the simulated discharges were adequately correlated with the observed ones, with the marginally best results presented in the case of precipitation and temperature of 0.25 degrees x 0.25 degrees spatial analysis. The results of the research indicate that the selection of ERA-Interim data can indeed improve or facilitate the researcher's outputs when dealing with regional hydrologic simulations.