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| Titel |
R-tools for estimating exceedance probabilities of Envelope Curves of hydrological extremes |
| VerfasserIn |
Björn Guse, Attilio Castellarin |
| Konferenz |
EGU General Assembly 2013
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 15 (2013) |
| Datensatznummer |
250084576
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| Zusammenfassung |
| Envelope curves of flood flows are classical hydrological tools that graphically summarize the
current bound on our experience of extreme floods in a region. Castellarin et al. [2005]
introduced Probabilistic Regional Envelope Curves (PRECs) and formulated an empirical
estimator of the recurrence interval T associated with the curves themselves. PRECs can be
used to estimate the T -year flood (design-flood) for any basin in a given region as a function
of the catchment area alone. We present a collection of R-functions that can be used for (1)
constructing the empirical envelope curve of flood flows for a given hydrological region and
(2) estimating the curve’s T on the basis of a mathematical representation of the
cross-correlation structure of observed flood sequences. The R functions, which we tested on
synthetic regional datasets of annual sequences characterized by different degrees of
cross-correlation generated through Monte Carlo resampling, implement the algorithm
proposed in Castellarin [2007], providing the user with straightforward means for
predicting the exceedance probability 1-T associated with a regional envelope curve,
and therefore the T -year flood in any ungauged basin in the region for large and
very large T values. Furthermore, the algorithm can be easily coupled with other
regional flood frequency analysis procedures to effectively improve the accuracy
of flood quantile estimates at high T values [Guse et al., 2010], or extended to
rainfall extremes for predicting extreme point-rainfall depths associated with a given
duration and recurrence interval in any ungauged site within a region [Viglione et al.,
2012].
References
Castellarin (2007): Probabilistic envelope curves for design flood estimation at ungauged
sites, Water Resour. Res., 43, W04406.
Castellarin, Vogel, Matalas (2005): Probabilistic behavior of a regional envelope curve,
Water Resour. Res., 41, W06018.
Guse, Hofherr, Merz (2010): Introducing empirical and probabilistic regional envelope
curves into a mixed bounded distribution function, Hydrol. Earth Syst. Sci., 14,
2465-2478.
Viglione, Castellarin, Merz, Blöschl (2012): Extreme rainstorms: Comparing regional
envelope curves to stochastically generated events, Water Resour. Res., 48, W01509. |
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