Hydrology and Earth System Sciences www.hydrol-earth-syst-sci.net 1027-5606 1607-7938 13 3 2009 10.5194/hess-13-293-2009 http://www.hydrol-earth-syst-sci.net/13/293/2009/ http://www.hydrol-earth-syst-sci.net/13/293/2009/hess-13-293-2009.html http://www.hydrol-earth-syst-sci.net/13/293/2009/hess-13-293-2009.pdf 293 303 2009-03-06 Uncertainty analysis of hydrological ensemble forecasts in a distributed model utilising short-range rainfall prediction Y. Xuan y.xuan@unesco-ihe.org I. D. Cluckie Y. Wang Dept. of Hydroinformatics and Knowledge Management, UNESCO-IHE Institute for Water Education, 2611 AX, Delft, The Netherlands Water and Environmental Management Research Centre (WEMRC), Dept. of Civil Engineering, University of Bristol, Bristol, BS8 1UP, UK Taiwan Typhoon and Flood Research Institute, Taichung 40763, Taiwan Advances in mesoscale numerical weather predication make it possible to provide rainfall forecasts along with many other data fields at increasingly higher spatial resolutions. It is currently possible to incorporate high-resolution NWPs directly into flood forecasting systems in order to obtain an extended lead time. It is recognised, however, that direct application of rainfall outputs from the NWP model can contribute considerable uncertainty to the final river flow forecasts as the uncertainties inherent in the NWP are propagated into hydrological domains and can also be magnified by the scaling process. 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