Estimating the impact of climate change on peak flows in the River Rhine

Two statistical methods were evaluated to bridge the gap between the coarse water balance models and the daily time scale required to estimate changes in peak flows under changed climate conditions. The first method (referred to as the "Conditional Peak Model") is based on empirical relationships between 10-daily or monthly average discharges and peak flows. The second method ( referred to as the "Wavelet Disaggregation Model") comprises statistical disaggregation of series of 10-daily and monthly average discharges to the requested daily time step using the so-called wavelet technique. Using the RHINEFLOW model, the effects of climate change on the monthly and 10-daily average discharge of the Rhine were calculated. Subsequently, using the two statistical techniques, discharge extremes and their frequencies were estimated from the RHINEFLOW output.