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| Titel |
Intercomparison of DEM-based approaches for the identification of flood-prone areas in different geomorphologic and climatic conditions |
| VerfasserIn |
Caterina Samela, Fernando Nardi, Salvatore Grimaldi, Francesco De Paola, Aurelia Sole, Salvatore Manfreda |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250098058
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| Publikation (Nr.) |
 EGU/EGU2014-13698.pdf |
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| Zusammenfassung |
| Floods represent the most critical natural hazard for many countries and their frequency
appears to be increasing in recent times. The legal constraints of public administrators and the
growing interest of private companies (e.g., insurance companies) in identifying the areas
exposed to the flood risk, is determining the necessity of developing new tools for the risk
classification over large areas. Nowadays, among the numerous hydrologic and hydraulic
methods regularly used for practical applications, 2-D hydraulic modeling represents the
most accurate approach for deriving detailed inundation maps. Nevertheless, data
requirement for these modeling approaches is certainly onerous, limiting their applicability
over large areas.
On this issue, the terrain morphology may provide an extraordinary amount of
information useful to detect areas that are particularly prone to serious flooding. In the
present work, we compare the reliability of different DEM-derived quantitative morphologic
descriptors in characterizing the relationships between geomorphic attributes and flood
exposure. The tests are carried out using techniques of pattern classification, such as linear
binary classifiers (Degiorgis et al., 2012), whose ability is evaluated through performance
measures. Simple and composed morphologic features are taken into account. The
morphological features are: the upslope contributing area (A), the local slope (S), the length
of the path that hydrologically connects the location under exam to the nearest element of the
drainage network (D), the difference in elevation between the cell under exam and the
final point of the same path (H), the curvature (-2H). In addition to the mentioned
features, the study takes into consideration a number of composed indices, such as:
the modified topographic index (Manfreda et al., 2011), the downslope index (DI)
proposed by Hjerdt et al. (2004), the ratio between the elevation difference H and the
distance to the network D, and other indices. Each binary classifier is applied in
several catchments in order to verify the reproducibility of the procedures in different
geomorphologic, climatic and hydrologic conditions. The study explores the use of these
procedures in gauged river basins located in Italy and in an ungauged basin located in
Africa.
References
Degiorgis, M., G. Gnecco, S. Gorni, G. Roth, M. Sanguineti, A.C. Taramasso, 2012.
Classifiers for the detection of flood-prone areas using remote sensed elevation data, J.
Hydrol., 470-471, 302–315.
Hjerdt, K. N., J.J. McDonnell, J. Seibert, A. Rodhe, A new topographic index to
quantify downslope controls on local drainage, Water Resour. Res., 40, W05602,
2004.
Manfreda, S., M. Di Leo, A. Sole, Detection of Flood Prone Areas using Digital Elevation
Models, J. Hydrol. Eng., 16(10), 781-790, 2011. |
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