Hydrology and Earth System Sciences www.hydrol-earth-syst-sci.net 1027-5606 1607-7938 12 2 2008 10.5194/hess-12-587-2008 http://www.hydrol-earth-syst-sci.net/12/587/2008/ http://www.hydrol-earth-syst-sci.net/12/587/2008/hess-12-587-2008.html http://www.hydrol-earth-syst-sci.net/12/587/2008/hess-12-587-2008.pdf 587 601 2008-03-19 Stochastic simulation experiment to assess radar rainfall retrieval uncertainties associated with attenuation and its correction R. Uijlenhoet remko.uijlenhoet@wur.nl A. Berne Hydrology and Quantitative Water Management Group, Department of Environmental Sciences, Wageningen University, The Netherlands Laboratoire de Télédétection Environnementale, EPF Lausanne, Switzerland As rainfall constitutes the main source of water for the terrestrial hydrological processes, accurate and reliable measurement and prediction of its spatial and temporal distribution over a wide range of scales is an important goal for hydrology. We investigate the potential of ground-based weather radar to provide such measurements through a theoretical analysis of some of the associated observation uncertainties. A stochastic model of range profiles of raindrop size distributions is employed in a Monte Carlo simulation experiment to investigate the rainfall retrieval uncertainties associated with weather radars operating at X-, C-, and S-band. We focus in particular on the errors and uncertainties associated with rain-induced signal attenuation and its correction for incoherent, non-polarimetric, single-frequency, operational weather radars. The performance of two attenuation correction schemes, the (forward) Hitschfeld-Bordan algorithm and the (backward) Marzoug-Amayenc algorithm, is analyzed for both moderate (assuming a 50 km path length) and intense Mediterranean rainfall (for a 30 km path). 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