Date of Submission

IPL Project Annual Report Form 2015 1 January 2015 to 31 December 2015

1. Project Title : Multi-scale rainfall triggering models for Early Warning of Landslides (MUSE)

2. Main Project Fields:

(1) Technology Development

A. Monitoring and Early Warning, B. Prediction of triggering in real-time

(3) Capacity Building

A. Setting up of Operational Early Warning Systems

3. Name of Project leader: Filippo Catani Affiliation: Associate Professor, Department of Earth Sciences University of Florence (DST-UNIFI)Contact: Via La Pira, 4, 50121 Florence (Italy), tel. +390552757559, filippo.catani@unifi.it

Core members of the Project: Nicola Casagli, Professor, DST-UNIFI Veronica Tofani, Assistant Professor, DST-UNIFI Riccardo Fanti, Assistant Professor, DST-UNIFI Samuele Segoni, Research Assistant, DST-UNIFI

4. Objectives:

The main objective of this candidate IPL project will be the enhancement of knowledge and methodologies related to the integration of landslide prediction models at different scales to build an effective operational multi-scale system for real-time early warning of rainfall triggered mass movements

5. Study Area:

For the first phase of the project, the study area will be Northern Tuscany (about 3000 km2), characterized by recent intense landslide occurrences. Then, a larger area will be selected for the national-scale application..

6. Project Duration: 3 years

7. Report

1) Progress in the project: (30 lines maximum)

During the first year of the project the activities carried out are mainly related to WP1 and WP2.

WP1: Soil properties variability study.

In particular the activity has focused on the characterization of geotechnical properties of the soil cover of the hillslopes in Tuscany (Central Italy;) in order to improve the reliability of deterministic models output such as the HIRESSS (HIgh REsolution Slope Stability Simulator; Rossi et al., 2013). This software makes use of Monte Carlo simulation technique to manage the uncertainty typical of geotechnical and hydrological input parameters, which is a common weakness of deterministic models. Uncertainty in the geotechnical input parameter values can be solved by using a frequency distribution model for the parameters. This helps to restrict the number of in situ and laboratory measurements and is crucial to reduce computation time within HIRESSS and other similar distributed numerical models at the basin scale.

In the Tuscany region (Figure 1) 130 survey points were selected. The following in situ measurements were performed at each survey point: i) shear strength under natural conditions by mean of the Borehole Shear Test (BST; Lutenegger and Halberg 1981) jointly with the ii) matric suction obtained with a tensiometer iii) saturated hydraulic conductivity ksat) by means of the constant-head well permeameter Amoozemeter (Amoozegar, 1989) and iv) sampling of two aliquots (~2 kg each) of the material for laboratory tests. The BST allows the measure of shear strength parameters under natural in-situ conditions.

In addition to the in situ measures, the grain size distribution and the relationships of phases (porosity, dry unit weight γd) are determined in the laboratory following the ASTM (American Society for Testing and Materials) recommendations (ASTM D422-63 2007, ASTM D2217-85 1998 and ASTM D-4318 2010).

The geotechnical parameters measured have been statistically analyzed and linked to the main lithologies of the bedrock in order to define the input hydrological and geotechnical parameters for the HIRESSS model. The HIRESSS code has been applied in a selected study area located in Northern Tuscany in order to test the performance of the models with the measured geotechnical and hydrological parameters (figure 1). Further applications will be carried out in order to test the sensitivity of the model to the variation of the model results.

Figure 1: Detail of the factor of safety map derived from the application of the HIRESSS t the study area in Tuscany (Italy).

WP2. Analysis and integration of rainfall data and rainfall forecasts.

During the first year, the system of collection, storage and querying of meteorological data was implemented with the creation of an efficient database that allows both to store historical records and real-time data coming from the National Radar Network and also from the rainfall network belonging to the National Civil Protection. In this way, new data can be continuously added to the already stored files in the same format through the same indexing procedures. Therefore, this reference platform was necessary to transfer the physically-based model (HIRESSS) from a first experimental scientific software to an operative system for real-time applications at regional scale.

2) Planned future activities or Statement of completion of the Project

For the next year the activities foreseen are:

1. Further applications of the HIRESSS model in selected test sites in order to define the sensitivity of the model to the variations of the input data (geotechnical and hydrological properties)

2. Further improvements on the integration and harmonization of rainfall data of different type (measured and predicted) within the early warning system based on the HIRESSS

model. In this approach, a new algorithm for the extraction of soil moisture from Sentinel SAR data will be tested to infer spatially distributed near-real time data on soil saturation.

3. Creation of an integrated and effective early warning system which will be able to work at 2 levels: a regional level to highlight alert zones with a suitable lead time and a local level, activated on purpose, where a detail scale deterministic model such as HIRESSS will run to provide maps of distributed probability for the factor of safety of slopes in near real-time.

3) Beneficiaries of Project for Science, Education and/or Society

The beneficiaries of this project are several: Civil Protection offices and institution, Research institutes, Universities, Public administrations, International organizations.

4) Results:

G. Bicocchi, M. D’Ambrosio, G. Rossi, A. Rosi, C. Tacconi-Stefanelli, S. Segoni, M. Nocentini, P. Vannocci, V. Tofani, N. Casagli & F. Catani (Accepted) Geotechnical in situ measures to improve landslides forecasting models: a case study in Tuscany (Central Italy) – Proceedings of the 12th International Symposium on Landslides, June 12th-19th , 2016, Napoli, Italy.

G. Bicocchi, M. D’ambrosio, P. Vannocci, M. Nocentini C. Tacconi-Stefanelli, E. B. Masi, S. Carnicelli, V. Tofani, F. Catani (2015) Preliminary assessment of the factors controlling the geotechnical and hydrological properties in the hillslope deposits of Eastern Tuscany (Central Italy) Proceedings of IAMG 2015

Note:

1) If you will change items 1)-6) from the proposal, please write the revised content in Red. 2) Please fill and submit this form by 1 February 2016 to ICL Network <icl-network@iclhq.org>