277 Monitoring and Modelling of Soil–Atmosphere Interaction on a Slope Affected by Shallow Landslides Roberto Valentino, Massimiliano Bordoni, Claudia Meisina, Davide Zizioli, Marco Bittelli, and Silvia Chersich Abstract A long-term field monitoring proves very helpful to understand the effect of climatic variables on the hydrological response of a shallow soil and the role of atmospheric features in the triggering mechanism of rainfall-induced landslides. In this work, field measurements of the soil saturation in a sample slope, coming from 18 months continuous monitoring of soil water content, are presented. The experimental data are compared with the seasonal trends of the soil saturation resulting from the application of a simplified empirical model, based on rainfall and air temperature input data. The performance of the model is evaluated for two different soil depths, in order to establish a future application of this method to predict time trends of the saturation for large scale slope stability analyses. Keywords Soil saturation  Antecedent rainfall thresholds  Early warning system 277.1 Introduction and Aim of the Work Shallow landslides are hazardous phenomena usually trig- gered by intense rainfall events. Although they involve superficial deposits of small thickness (till 1.5–2 m from ground level) and small volumes of soil, when occurring close to urbanised areas, they can cause significant damage to structures, infrastructures, cultivations and, sometimes, result in human loss. For this reason, it is very important to understand the hydro-mechanical response of soils to dif- ferent rainfall events, and to identify the factors which trigger shallow landslides. In order to estimate these factors, a long-term field continuous monitoring of soil hydrological and mechanical behaviour is needed (Godt et al. 2009; Smethurst et al. 2012; Springman et al. 2013). One of the hydrological parameters which assumes a basic importance in rainfall-induced shallow landslide analysis and consequent identification of potential instability is soil saturation (S r ) (Tsai et al. 2008). To obtain a time trend of the saturation of a shallow soil, a continuous monitoring of this parameter is fundamental. In this work, the measured saturation at different depths in a slope sus- ceptible to shallow landslides is compared with the satura- tion estimated through an empirical model, which takes into account rainfall and air temperature as basic input variables. The performance of the model is also considered in view of a future application at different scales to estimate the time trends of the saturation and as a potentially useful tool for rainfall-induced shallow landslides prediction. R. Valentino (&) Department of Civil, Environmental, Territorial Engineering and Architecture, University of Parma, Parma, Italy e-mail: roberto.valentino@unipr.it M. Bordoni  C. Meisina  D. Zizioli  S. Chersich Department of Earth and Environment Sciences, University of Pavia, Pavia, Italy e-mail: massimiliano.bordoni01@universitadipavia.it M. Bittelli Department of Agricultural Science, University of Bologna, Bologna, Italy G. Lollino et al. (eds.), Engineering Geology for Society and Territory – Volume 2, DOI: 10.1007/978-3-319-09057-3_277, © Springer International Publishing Switzerland 2015 1563