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RESEARCH PRODUCT
Exploiting historical rainfall and landslide data in a spatial database for the derivation of critical rainfall thresholds
Domenico CaraccioloLeonardo NotoF Lo ContiElisa Arnonesubject
Antecedent rainfall condition010504 meteorology & atmospheric sciencesMeteorology0211 other engineering and technologiesSoil ScienceContext (language use)02 engineering and technologyRainfall–landslide database01 natural sciencesImage analysisEnvironmental ChemistryRainfall thresholds; Rainfall–landslide database; Image analysis; Antecedent rainfall conditions; Sicily; LithologyPrecipitationSicily0105 earth and related environmental sciencesEarth-Surface ProcessesWater Science and TechnologyEvent (probability theory)021110 strategic defence & security studiesGlobal and Planetary ChangeRainfall thresholdsSpatial databaseSettore ICAR/02 - Costruzioni Idrauliche E Marittime E IdrologiaAntecedent rainfall conditionsGeologyLandslideRainfall thresholdPollutionHazardRunoff modelLithologyHyetographImage analysiGeologydescription
Critical rainfall thresholds for landslides are powerful tools for preventing landslide hazard. The thresholds are commonly estimated empirically starting from rainfall events that triggered landslides in the past. The creation of the appropriate rainfall–landslide database is one of the main efforts in this approach. In fact, an accurate agreement between the landslide and rainfall information, in terms of location and timing, is essential in order to correctly estimate the rainfall–landslide relationships. A further issue is taking into account the average moisture conditions prior the triggering event, which reasonably may be crucial in determining the sufficient amount of precipitation. In this context, the aim of this paper is exploiting historical landslide and rainfall data in a spatial database for the derivation of critical rainfall thresholds for landslide occurrence in Sicily, southern Italy. The hourly rainfall events that caused landslides occurred in the twentieth century were specifically identified and reconstructed. A procedure was proposed to automatically convert rain guages charts recorded on paper tape into digital format and then to provide the cumulative rainfall hyetograph in digital format. This procedure is based on a segmentation followed by signal recognition techniques which allow to digitalize and to recognize the hyetograph automatically. The role of rainfall prior to the landslide events was taken into account by including in the analysis the rainfall occurred 5, 15 and 30 days before each landslide. Finally, cumulated rainfall duration thresholds for different exceedance probability levels were determined. The obtained thresholds resulted in agreement with the regional curves proposed by other authors for the same area; antecedent rainfall turned out to be particularly important in triggering landslides.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2017-03-01 | Environmental Earth Sciences |