Evaluation of variations in frequency of landslide events affecting pyroclastic covers in Campania region under the effect of climate changes

Abstract

In recent years, pyroclastic covers mantling slopes in the Campania region of southern Italy have frequently been affected by flowslides. Due to high exposure and demographic pressure in these areas, assessment of the potential effects of climate change on the frequency of such events has become a crucial issue. In this regard, our paper proposes a simulation chain comprising three main elements: (i) climate simulation at the highest horizontal resolution available for Italy (8 km); (ii) a bias correction procedure in an attempt to remove systematic errors in the entire weather forcing probability distribution; (iii) the data obtained used as input for an interpretative tool estimating the evolution of soil pore water pressure and water storage (bulk water content) by means of a well-calibrated coupled thermo-hydraulic approach able to adequately take into account soil-atmosphere interaction dynamics. The predictive ability of the geotechnical model to reproduce failure conditions was tested by forcing it with temperature and precipitation observations. Subsequently, the performance of the entire modeling chain was evaluated for a period from 1981 to 2010. Lastly, variations in landslide occurrence were assessed up to 2100 under two concentration scenarios. An increase with different features was estimated under both scenarios depending on the time horizon and the severity of the concentration scenario.