La Houille Blanche
Number 6, Décembre 2006
|Page(s)||22 - 26|
|Published online||01 June 2007|
Quelques illustrations des sources d’incertitudes dans l’analyse de l’aléa pluvieux
Some examples of uncertainties in rainfall hazard study
UMR HydroSciences Montpellier Université Montpellier II, MSE, place Eugène Bataillon, 34095 Montpellier cedex 5
Auteur de correspondance : firstname.lastname@example.org
Some examples of uncertainties in rainfall hazard study. Three type of uncertainties related to rainfall hazard study are presented. The first one concerns the measurement of extreme rainfall using a sparse rain gage network: it has been shown that before 1945, the probability that a rainfall event less than 200 km2 is not measured by the network, is up to three times more important comparing to the current period of observation. The second point is about the shape of the probability distribution of frequency (PDF) of the daily maxima annual rainfall: does the tail of the distribution correspond to a Gumbel PDF or does it show an “hyper exponential” behaviour? According to the chronics duration, one can difficulty argue while analysing a single rainfall chronic because of sampling uncertainties. It has been shown that a regional PDF has an hyper exponential tail. The quantiles are less subject to sampling variability comparing to the one obtain with a local PDF fitting. In the last point the mean area rainfall PDF is studied according to the area. A scale relation between the PDF corresponding to different areas is presented. The sampling variability of the PDF shape parameter is presented. Conclusion concerning the asymptotic behaviour of the mean areal rainfall PDF needs further analysis.
Mots clés : Valeurs Rares et extrêmes de précipitations et de débits
© Société Hydrotechnique de France, 2006
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.