Budyko-based approach for modelling water balance dynamics considering environmental change drivers in the Vistula River basin, Poland

ABSTRACT The spatiotemporal variations in the water balance caused by environmental changes lead to unsteady-state conditions with long- and short-term implications for social and economic conditions. The aim of this study is to extend the current knowledge of the Budyko approach in unsteady-state conditions and the importance of model structural uncertainties. We used three Budyko-based models (Turc-Pike, Zhang, Fu) with and without the concept of effective precipitation scenarios. The effective precipitation and model parameters were determined together during the calibration processes. The effective precipitation-based approach improved the model performance in predicting the annual water balance in most of the River Vistula catchment. We also discuss the importance of considering structural uncertainties in water balance modelling. Climate change is the main driver for the changes in the water balance of the River Vistula. The estimation of water balance dynamics, considering environmental changes, is essential to understand the changes in hydrological processes.