1Consiglio Nazionale delle Ricerche, Istituto di Ricerca per la
Protezione Idrogeologica, via Madonna Alta 126, 06128 Perugia, Italy
2Consiglio Nazionale delle Ricerche, Istituto di Ricerca per la
Protezione Idrogeologica, via Amendola 122, 70126 Bari, Italy
3Regione Puglia, Servizio di Protezione Civile, Via delle Magnolie 6/8,
70126 Modugno (Bari), Italy
4University of Naples “Federico II”, Naples, Italy
5University of Chieti-Pescara “Gabriele D'Annunzio”, Chieti, Italy
6University of Molise, Department of Biosciences and Territory,
Contrada Fonte Lappone, Pesche (IS), Italy
apresent address: University “Aldo Moro”, Department of Earth and
Environmental Sciences, Via Orabona 7, 70126 Bari, Italy
Received: 23 Sep 2016 – Discussion started: 31 Oct 2016
Abstract. In karst environments, heavy rainfall is known to cause multiple geohydrological hazards, including inundations, flash floods, landslides and sinkholes. We studied a period of intense rainfall from 1 to 6 September 2014 in the Gargano Promontory, a karst area in Puglia, southern Italy. In the period, a sequence of torrential rainfall events caused severe damage and claimed two fatalities. The amount and accuracy of the geographical and temporal information varied for the different hazards. The temporal information was most accurate for the inundation caused by a major river, less accurate for flash floods caused by minor torrents and even less accurate for landslides. For sinkholes, only generic information on the period of occurrence of the failures was available. Our analysis revealed that in the promontory, rainfall-driven hazards occurred in response to extreme meteorological conditions and that the karst landscape responded to the torrential rainfall with a threshold behaviour. We exploited the rainfall and the landslide information to design the new ensemble–non-exceedance probability (E-NEP) algorithm for the quantitative evaluation of the possible occurrence of rainfall-induced landslides and of related geohydrological hazards. The ensemble of the metrics produced by the E-NEP algorithm provided better diagnostics than the single metrics often used for landslide forecasting, including rainfall duration, cumulated rainfall and rainfall intensity. We expect that the E-NEP algorithm will be useful for landslide early warning in karst areas and in other similar environments. We acknowledge that further tests are needed to evaluate the algorithm in different meteorological, geological and physiographical settings.
Revised: 08 Feb 2017 – Accepted: 24 Feb 2017 – Published: 22 Mar 2017
Martinotti, M. E., Pisano, L., Marchesini, I., Rossi, M., Peruccacci, S., Brunetti, M. T., Melillo, M., Amoruso, G., Loiacono, P., Vennari, C., Vessia, G., Trabace, M., Parise, M., and Guzzetti, F.: Landslides, floods and sinkholes in a karst environment: the 1–6 September 2014 Gargano event, southern Italy, Nat. Hazards Earth Syst. Sci., 17, 467-480, doi:10.5194/nhess-17-467-2017, 2017.