TXT-tool 2.039-1.1 Italian National Early Warning System

Abstract

In Italy rainfall-induced slope failures occur every year, claiming lives and causing severe economic disruptions. We have designed and implemented a warning system, named SANF (an acronym for national early warning system for rainfall-induced landslides), to forecast the possible occurrence of rainfall-induced landslides. The system is based on: (i) rainfall thresholds for possible landslide occurrence, (ii) sub-hourly rainfall measurements obtained by a nationwide network of 1950 rain gauges, and (iii) quantitative rainfall forecasts. All system components exploit Open Source software. Twice a day the system compares the measured and the forecasted rainfall amounts against pre-defined thresholds, and assigns to each rain gauge a probability of landslide occurrence. This information is used to prepare synoptic-scale maps showing where rainfall-induced landslides are expected. The system outputs are delivered to the National Civil Protection Authorities in different formats. Spatial outputs are published as standard OGC (Open Geospatial Consortium) web services (WMS, WFS, WCS) by the IRPI Spatial Data Infrastructure (IRPI SDI). A password protected WebGIS interface facilitates the use of the system by the Civil Protection personnel and gives access to current and past forecasts. In addition, bulletins containing the system information can be generated automatically and sent via e-mail to the Civil Protection personnel. In a more recent implementation, the system calculate hourly-based forecast using new regional rainfall thresholds and combine landslide forecasts with landslide susceptibility information available at synoptic scale in the national territory. Improvements of the validation procedures and of the landslide susceptibility layer are currently underway.