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| Titel |
Assessing potential modifications of landslide triggering probability based on hydromechanical modelling and regional climate model projections |
| VerfasserIn |
David Johnny Peres, Antonino Cancelliere |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250145513
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| Publikation (Nr.) |
 EGU/EGU2017-9459.pdf |
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| Zusammenfassung |
| Climate change related to uncontrolled greenhouse gas emissions is expected to
modify climate characteristics in a harmful way, increasing the frequency of many
precipitation-triggered natural hazards, landslides included.
In our study we analyse regional climate model (RCM) projections with the aim of
assessing the potential future modifications of rainfall event characteristics linked to shallow
landslide triggering, such as: event duration, total depth, and inter-arrival time. Factor of
changes of the mean and the variance of these rainfall-event characteristics are exploited to
adjust a stochastic rainfall generator aimed at simulating precipitation series likely to occur in
the future. Then Monte Carlo simulations – where the stochastic rainfall generator and a
physically based hydromechanical model are coupled – are carried out to estimate the
probability of landslide triggering for future time horizons, and its changes respect to the
current climate conditions.
The proposed methodology is applied to the Peloritani region in Sicily, Italy, an area that
in the past two decades has experienced several catastrophic shallow and rapidly moving
landslide events. Different RCM simulations from the Coordinated regional Climate
Downscaling Experiment (CORDEX) initiative are considered in the application, as well as
two different emission scenarios, known as Representative Concentration Pathways:
intermediate (RCP 4.5) and high-emissions (RCP 8.5).
The estimated rainfall event characteristics modifications differ significantly both in
magnitude and in direction (increase/decrease) from one model to another. RCMs are
concordant only in predicting an increase of the mean of inter-event dry intervals. The
variance of rainfall depth exhibits maximum changes (increase or decrease depending on the
RCM), and it is the characteristic to which landslide triggering seems to be more sensitive.
Some RCMs indicate significant variations of landslide probability due to climate change
(up to a factor of 10), while for other climate models variations are small. The
variability of the indications resulting from different RCMs is a sign of the significant
degree of uncertainty involved in climate change impact assessments for landslides. |
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