Calibration of The LISFLOOD Model For Europe: Current Status And Way Forward
The hydrological model LISFLOOD model forms the core of the European Flood Alert System (EFAS) and is used for impact studies to evaluate the effect of changes in land use and climate on the hydrological behaviour in catchments across Europe. The accuracy of the model predictions depends on the ability of the model to capture the dominating hydrological processes that transfer precipitation into river runoff at the catchment scale, and on its ability to reproduce historical time series of observed river discharges. A crucial step which contributes significantly to the accuracy of the LISFLOOD forecasts and simulations is the calibration of the model for all European catchments. Owing to the general nature of LISFLOOD, its application to any given river basin requires that certain parameters of conceptual functions be identified for the particular basin. An automatic calibration procedure has been developed for LISFLOOD, based on the Shuffled Complex Evolution Metropolis (SCEM-UA) global optimization algorithm [Vrugt et al., 2003]. The algorithm automatically searches through the space of feasible parameter values and finds the parameter values that produce the best model performance. It also yields a posterior parameter distribution, which reflects the residual uncertainty about the model parameters after taking into account the discharge observations. The posterior distribution forms the basis for making probabilistic flow predictions. To overcome the computational burden the optimization has been implemented using parallel computing. This document outlines the automatic calibration method and shows results for the Meuse and Morave catchments.