HESSD Hydrology and Earth System Sciences Discussions HESSD Hydrol. Earth Syst. Sci. Discuss. 1812-2116 Göttingen, Germany 10.5194/hessd-8-1469-2011 Parameter uncertainty and sensitivity analysis in sediment flux calculation Cheviron B. 1 Delmas M. 2 Cerdan O. 2 Mouchel J.-M. 1 Université Paris VI-Pierre et Marie Curie, UMR 7619 Sisyphe, 4, Place Jussieu, 75252 Paris Cedex 05, France BRGM – RNSC – 3, avenue Claude Guillemin, BP 6009, 45060 Orléans Cedex 2, France 28 01 2011 8 1 1469 1506 Copyright: © 2011 B. Cheviron et al. 2011 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://hess.copernicus.org/preprints/8/1469/2011/hessd-8-1469-2011.html The full text article is available as a PDF file from https://hess.copernicus.org/preprints/8/1469/2011/hessd-8-1469-2011.pdf

This paper examines uncertainties in the calculation of annual sediment budgets at the outlet of rivers. Emphasis is put on the sensitivity of power-law rating curves to degradations of the available discharge-concentration data. The main purpose is to determine how predictions arising from usual or modified power laws resist to the infrequence of concentration data and to relative uncertainties affecting source data. This study identifies cases in which the error on the estimated sediment fluxes remains of the same order of magnitude or even inferior to these in source data, provided the number of concentration data is high enough. The exposed mathematical framework allows considering all limitations at once in further detailed investigations. It is applied here to bound the error on sediment budgets for the major French rivers to the sea.

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