Hydrology and Earth System Sciences www.hydrol-earth-syst-sci.net 1027-5606 1607-7938 13 6 2009 10.5194/hess-13-913-2009 http://www.hydrol-earth-syst-sci.net/13/913/2009/ http://www.hydrol-earth-syst-sci.net/13/913/2009/hess-13-913-2009.html http://www.hydrol-earth-syst-sci.net/13/913/2009/hess-13-913-2009.pdf 913 921 2009-06-25 Uncertainty in river discharge observations: a quantitative analysis G. Di Baldassarre g.dibaldassarre@unesco-ihe.org A. Montanari Department of Hydroinformatics and Knowledge Management, UNESCO-IHE Institute for Water Education, Delft, The Netherlands Faculty of Engineering, University of Bologna, Bologna, Italy This study proposes a framework for analysing and quantifying the uncertainty of river flow data. Such uncertainty is often considered to be negligible with respect to other approximations affecting hydrological studies. 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