Advances in Geosciences www.adv-geosci.net 1680-7340 1680-7359 17 9th EGU Plinius Conference on Mediterranean Storms (2007) 2009 10.5194/adgeo-17-111-2009 http://www.adv-geosci.net/17/111/2009/ http://www.adv-geosci.net/17/111/2009/adgeo-17-111-2009.html http://www.adv-geosci.net/17/111/2009/adgeo-17-111-2009.pdf 111 117 2009-03-16 Operational flood-forecasting in the Piemonte region – development and verification of a fully distributed physically-oriented hydrological model D. Rabuffetti davide.rabuffetti@arpa.piemonte.it G. Ravazzani S. Barbero M. Mancini ARPA Piemonte – Monitoring and forecasting area, 10135 Torino, Italy DIIAR-CIMI Politecnico di Milano, Milano, Italy A hydrological model for real time flood forecasting to Civil Protection services requires reliability and rapidity. At present, computational capabilities overcome the rapidity needs even when a fully distributed hydrological model is adopted for a large river catchment as the Upper Po river basin closed at Ponte Becca (nearly 40 000 km²). This approach allows simulating the whole domain and obtaining the responses of large as well as of medium and little sized sub-catchments. The FEST-WB hydrological model (Mancini, 1990; Montaldo et al., 2007; Rabuffetti et al., 2008) is implemented. The calibration and verification activities are based on more than 100 flood events, occurred along the main tributaries of the Po river in the period 2000–2003. More than 300 meteorological stations are used to obtain the forcing fields, 10 cross sections with continuous and reliable discharge time series are used for calibration while verification is performed on about 40 monitored cross sections. Furthermore meteorological forecasting models are used to force the hydrological model with Quantitative Precipitation Forecasts (QPFs) for 36 h horizon in "operational setting" experiments. Particular care is devoted to understanding how QPF affects the accuracy of the Quantitative Discharge Forecasts (QDFs) and to assessing the QDF uncertainty impact on the warning system reliability. Results are presented either in terms of QDF and of warning issues highlighting the importance of an "operational based" verification approach. Bartholmes, J. and Todini, E.: Coupling meteorological and hydrological models for flood forecasting, Hydrol. Earth Syst. Sci., 9, 333–346, 2005. Buizza, R., Asensio, H., Balint, G., Bartholmes, J., Bliefernicht, J., Bogner, K., Chavaux, F., de Roo, A., Donnadille, J., Ducrocq, V., Edlund, C., Kotroni, V., Krahe, P., Kunz, M., Lacire, K., Lelay, M., Marsigli, C., Milelli, M., Montani, A., Pappenberger, F., Rabuffetti, D., Ramos, M.-H., Ritter, B., Schipper, J. 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