Prediction of rainfall-induced landslides and associated risk in Italy

In Italy, intense or prolonged rainfall is the primary trigger of landslides, and rainfall-induced slope failures occur every year, claiming lives, causing economic disruption, and producing different environmental problems. Prediction of rainfall-induced landslides is a challenging task of both scientific and societal interest. The prediction is complicated by the fact that the pattern and intensity of rainfall varies with time, driven by natural variations and changes in climate. The project aims at establishing rainfall thresholds for the possible initiation of landslides in Italy, and at developing the rationale and the tools for the best exploitation of the established thresholds in a nation-wide rainfall warning system managed by the National Department of Civil Protection. During the first phase of the project, regional rainfall intensity – rainfall duration (ID) thresholds will be established, and used to forecast the possible occurrence of landslides. Next, the ID thresholds will be refined, and new thresholds will be defined and implemented in the national rainfall warning system. The possible occurrence of slope instabilities will be decided based upon: (i) rainfall measurements and forecasts, (ii) the available initiation thresholds – at different scales – and (ii) the outcomes of a twin research project aimed at zoning landslide susceptibility, hazard, and risk in Italy. The 5-year research and development project (2007-2011) is financed by the Italian National Department of Civil Protection, in the framework of a long-term research and development initiative conducted in cooperation with the Italian National Research Council (Consiglio Nazionale delle Ricerche, CNR). The project is lead by the Istituto di Ricerca per la Protezione Idrogeologica (IRPI). To achieve the project goals, IRPI coordinates a team of national and international scientists.