Weather modifications due to climate change will strongly influence hydrological cycles and, as a consequence, will produce a direct impact on the stability of slopes.
The availability of data about precipitations and the displacement field of a slow deep slide in clay active in Orvieto (Central Italy), monitored since more than 30 years, highlights a clear correspondence between rate of movement and rainfall features. Thus, the possibility that the long-term landslide activity could be influenced by modifications in the rainfall regime is very likely.
In a paper recently released on Procedia Earth and Planetary Science, a team of scientists (among them, CMCC researchers G. Rianna, A. Zollo and P. Mercogliano from ISC Division) realized an evaluation of the likely effects of the ongoing climate changes on the future landslide behaviour, that is a quantitative estimation of the displacement that could occur until the end of 21st century. To this aim, a detailed analysis of local rainfall history and of monitoring data has been coupled to high-resolution climate projections in the concerned area provided by the Regional Climate Model COSMO-CLM for two different emission scenarios.
Results highlighted that local climate effects should be responsible of a slow decrease in the displacement rate.

The abstract of the paper:
Forthcoming climate changes, recognized by the international scientific community, are inducing a modification of the hydrological cycles with a direct impact on the piezometric regime of natural slopes and thus on their stability conditions. Particularly regarding active landslides in fine grained soils, the experience based on several well documented cases suggests an evident connection between landslide activity and rainfalls cumulated over some months. As a consequence, the observed change of the rainfall features should provoke variations on the kinematic features of such phenomena. Its role could be not negligible in a landslide risk assessment.
Thanks to the availability of a considerable database related to the well documented Orvieto case, regarding precipitations and displacements of an active slide in clay, monitored since 1982, and to a climate projection occurring in the concerned area, provided by a reliable Regional Climate Model, the present paper gives a likely prediction of the long-term scenario of the landslide behavior. According to our results, local climate effects should be responsible of a slow decrease in the displacement rate.

Read and download the full paper:

Rianna G., Zollo A. L. , Tommasi P., Paciucci M., Comegna L., Mercogliano P.
Evaluation of the effects of climate changes on landslide activity of Orvieto clayey slope
2014, Procedia Earth and Planetary Science, vol 9, pp 54-63, DOI: 10.1016/j.proeps.2014.06.017