Towards More Resilient Communities – 3rd UC Lifeline Week Rome: 20-21-22 April 2015, L’Aquila: 23 April 2015, Naples: 24 April 2015

End-user and resilience oriented researches: creating worldwide networks Sapienza University of Rome

Models to support Emergency-management for Volcanic and and Landslide-induced Tsunami risks Paolo DE GIROLAMO

Sapienza University of Rome [email protected]

1

Aim of the presentation The aim of the presentation is: •  to introduce the problem of tsunami risk mitigation with reference to the Italian situation; •  to describe some specific problems of the Mediterranean Sea; •  to describe the operating landslide Tsunami Early Warning System of Stromboli (Eolian Islands – Italy)

2

Risk mitigation of natural phenomena The actions to be taken in order to mitigate the effect of natural phenomena can be listed referring to the interval between the time they are actually taken and the time of the natural phenomenon occurrence. In this respect, these actions can be identified as: a) preventive actions, i.e that are taken previously to the natural phenomenon occurrence; b) almost simultaneous actions, i.e. that taken at the natural phenomenon occurrence on the basis of the warning given by an effective Early Warning Systems (EWS); c) following actions, or actions taken after the occurrence of the natural phenomenon, i.e. aid actions

3

Tsunami risk mitigation in Italy In Italy, the national agency responsible for natural disaster mitigation is the Civil Protection Department- CPD. As far as the tsunamis are concerned, general guidelines referring to the actions to be taken in advance and after the time of occurrence of the phenomenon, does not exist yet in Italy. CPD has implemented at Stromboli (Italy) a Tsunami Early Warning System (TEWS) dedicated to tsunami generated by landslides. This is the only TEWS operating in the Mediterranean Sea.

4

Specific problems for TEWS in Mediterranean Sea

west part of the Med. sea

east part of the Med. sea

There are many tsunami sources in Mediterranean Sea located in the west, central and east part of the basin.

5

Specific problems for TEWS in Mediterranean Sea

west part of the Med. sea

east part of the Med. sea

The causes of tsunamis are mainly related to earthquakes and volcanic activities including landslides generated tsunamis. 6

Specific problems for TEWS in Mediterranean Sea

The Italian coasts are located in the middle of the basin and therefore tey are very exposed to tsunami risk.

7

Specific problems for TEWS in Mediterranean Sea

Stromboli 2002 Messina 1908

The most important and recent cases of tsunami occurred in Italy: •  Messina 1908 (about 80.000 victims); •  Stromboli 2002 (no victims).

8

Specific problems for TEWS in Mediterranean Sea

A specific problem in implementing a TEWS is due to the proximity of the tsunami sources to the coast at risk. => very short time available for a timely warning (between few minutes and few tens of minutes); => need to develop and implement an automatic or semiautomatic TEWS. 9

The Operating Landslide TEWS of Stromboli STROMBOLI

Italian Civil Protection Department

10

The Operating Landslide TEWS of Stromboli

STROMBOLI VOLCANO 11

The Operating Landslide TEWS of Stromboli

Ginostra Village

Stromboli Village

12

The Operating Landslide TEWS of Stromboli

≈ 900 m above MSL ≈ 2.900 m high

sea bottom

VOLCANIC CONE 13

The Operating Landslide TEWS of Stromboli SCIARA DEL FUOCO

14

The Operating Landslide TEWS of Stromboli

sub-aerial landslide submarine landslide

15

The Operating Landslide TEWS of Stromboli Stromboli 30 December 2002

N

E co

ast

Landslide Sciara del Fuoco –

16

The Operating Landslide TEWS of Stromboli

17

Theoretical aspects of the problem Overview of the physical processes Edge waves. Trapped on the beach, maximum surface elevation at the shoreline

Landslide coast -50 m -100 m -200 m -300 m

Free waves, propagating offshore 18

-400 m -500 m

The Operating Landslide TEWS of Stromboli Research activity

For this purpose physical model experiments were carried out in order to study the physical aspects of the problem and to obtain experimental data for the calibration and verification of numerical and analytical models to be employed in real situations.

19

Theoretical aspects of the problem

Schematic model of the landslide

coastline

CONICAL ISLAND Schematic model of Stromboli Island 20

≈9.0 m

Theoretical aspects of the problem

21

The Operating Landslide TEWS of Stromboli Measurements of the subaerial landslide superficial movements

Tsunami detection by sea level measurements

Sciara del Fuoco

22

The Operating Landslide TEWS of Stromboli Measurements of the subaerial landslide superficial movements Ground Base Interferometric Syntetic Aperture Radar - GBInSAR

Sciara del Fuoco

23

The Operating Landslide TEWS of Stromboli Measurements of the subaerial landslide superficial movements Time interval of 11 minutes (11.17-11.28 UT 9 March 2007)

speed greater than 300 mm/h

24

The Operating Landslide TEWS of Stromboli Tsunami detection by sea-level measurements Elastic beacon for tsunami detection

Sciara del Fuoco

25

The Operating Landslide TEWS of Stromboli All data coming from: -  landslide movements; -  sea level measurements; -  sesimic network are collected at the Advanced Operational Centre - COA Sciara del Fuoco

26

Risk mitigation by preventive and following actions PREVENTIVE ACTIONS The DPC has identified a number of road track that must be followed quickly by people to safe themselves in case of alarm. These pathways have been studied on the basis of a series of possible flooding scenarios obtained by numerical simulations.

27

Risk mitigation by preventive and following actions PREVENTIVE ACTIONS – Information leaflet Tsunamis

The coastline of Stromboli may rarely be affected by tsunamis. Tsunamis are caused by large landslides down the Sciara del Fuoco slope, and by powerful explosions or by earthquakes

28

Rules of conduct If, while visiting the coastal area, the sea retreats from the shore, or an earthquake or a loud explosion should occur, or in any case at sound of sirens, the visitor must make his way inland following the “exit” signs. If by boat take to the open sea

Risk mitigation by preventive and following actions FOLLOWING ACTIONS NEW HELIPORTS NEW WHARF (Ginostra) Sciara del Fuoco

29

Risk mitigation by preventive and following actions FOLLOWING ACTIONS – New wharf at Ginostra The smallest harbour in the world

The new wharf during a storm 30

TANKS FOR YOUR ATTENTION and welcome to Stromboli

31