While forecasting natural hazards is of obvious and increasing relevance in our fragile world, the methods and approaches used internationally are still poorly codified and agreed upon, ranging from qualitative evaluations to deterministic modelling to probabilistic approaches. The aim of the course is to review several such approaches, discuss their virtues and limits, and introduce the participants to the use of modern probabilistic approaches that incorporate the non-linear, chaotic nature of natural events.
The course is offered to early stage as well as more experienced researchers, and is co-sponsored by the EU/FP7 MC-ITN “NEMOH” (www.nemoh-itn.eu). It is organized over three lessons of 70 minutes each, followed by 20 minutes of discussion.

Lesson 1. Monday, April 28, h.17.30: Practices, issues, and challenges in natural hazard analysis (Warner Marzocchi, INGV)
In this lesson, we discuss in detail the general framework of the natural hazard analysis. We devote a particular attention to the treatment of the ubiquitous uncertainties of different nature, and to the role of models, data, and expert opinion in natural hazard assessment. We review some of the procedures commonly adopted in hazard analysis, highlighting some criticalities and future challenges. Finally, we discuss in general how a reliable hazard assessment can be rationally used to reduce natural risks.

Lesson 2. Tuesday, April 29, h.17.30: Probabilistic volcanic hazard analysis: methods and practice (Laura Sandri, INGV)
In this lesson, we introduce some of the most recent initiatives for assessing volcanic hazards. All theoretical and methodological details are explained through the application to one of the highest risk volcano, Campi Flegrei in Italy. In particular, we show how all information coming from models, data and expert opinion are merged to assess the ash fall hazard in the short- (days to few weeks) and long-term (years to decades).

Lesson 3. Wednesday, April 30, h.17.30: Probabilistic Seismic Hazard Assessment on regional scales: From current methods to new approaches (Jochen Woessner, ETH)
In this lesson, we review the general procedures of the long-term probabilistic seismic hazard analysis (PSHA). PSHA represents one of the most advanced example of quantitative hazard assessment and stands at the basis of the definition of the seismic building code. Then, we discuss a couple of recent real applications, related to the definition of the last European seismic hazard map developed in the framework of the European SHARE project, and to the establishment of the most recent seismic hazard in Switzerland.