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| Titel |
Extreme rainstorms: testing regional envelope curves against stochastically generated events |
| VerfasserIn |
Attilio Castellarin, Alberto Viglione, Magdalena Rogger, Ralf Merz, Günter Blöschl |
| Konferenz |
EGU General Assembly 2011
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 13 (2011) |
| Datensatznummer |
250053193
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| Zusammenfassung |
| The concept of regional envelope curves of flood flows was recently extended to extreme
rainstorm events by introducing the Depth-Duration Envelope Curves (DDEC).
DDEC are defined as regional upper bounds on observed rainfall maxima for several
rainfall durations, and their probabilistic interpretation enables one to estimate
the exceedance probability (or equivalently recurrence interval T ) of the curves
themselves. Even though probabilistic DDEC may in principle be used to retrieve point
rainfall quantiles for ungauged sites, the assessment of the reliability of envelope
rainfall-quantiles is not an easy task due to the large or very large T values associated
to DDEC. Also, DDEC were defined and tested only relative to a very specific
geographical and climatic region. In this study we derive DDEC for a wide study
region in Austria for durations ranging from 15 min to 24 h and we estimate the
corresponding T values. Then, for a subset of 21 raingauges, which are representative of the
climatic conditions of the entire area, we calibrate a stochastic rainfall generator and
generate very long (i.e., 50 000 years) 15 min rainfall series. Probabilistic DDEC
constructed for the study area are then compared with rainfall quantiles estimated
from the long synthetic series. The comparison is twofold: (1) verify how realistic
probabilistic envelope curves are for the study area and (2) assess the reliability of
rainfall quantiles obtained for large T-values from long synthetic rainfall series. |
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