MEDC MOUNT ETNA
• Supports rich agricultural land and it is estimated that 35% of Sicily’s population live on its slopes.
• The UN has classified it as a Decade Volcano due to its activity and nearby population.
• There have been at least 16 flank eruptions, and many summit eruptions, since 1600s. Since 2001, it has seen an eruption every year.
• It is well monitored and actively managed.
NATURE OF THE VOLCANIC HAZARD:
• Vineyards and orchards spread across the lower slopes and the Plain of Catania.
• It is a composite stratovolcano which typically erupts basaltic lava (low viscosity).
• Fissures also open up, releasing lava flows and ‘hornitos’ spatter lava from the side of the cone.
OTHER POTENTIAL HAZARDS: o Seismic activity connecting with eruptive activity – potential damage to buildings and infrastructure. o Gas plume emission, volcanic dust and ashfalls – high-magnitude explosive events at summit craters can lead to the formation of eruptive columns of ash, the fallout from which presents problems for settlement and agriculture. o Flank collapse before or following – one of the most hazardous processes – can lead to a huge avalanche of volcanic debris, as once occurred at the Valle del Bove. o Phreatic eruptions – steam-driven explosions when water beneath the ground is heated by magma or lava.
• In 1669 extensive lava flows engulfed Nicolosi, and in 1928 a large lava flow destroyed Mascali in just two days.
• In 2002-3 the biggest eruptions for many years threw up columns of ash that deposited material in Libya, 600km away. The eastern flanks of the volcano slipped by over 2m causing structural damage to houses.
IMPACT OF THE EVENT:
• 77 deaths can be attributed to eruptions on Mount Etna.
• The majority were caused when visitors strayed into hazardous areas, such as the nine tourists killed in September 1979 near Bocca Nuova by a phreatic explosion,
• In the last 20 years, all deaths on Etna have been due to lightening strikes and accidents.
• The eruptions of 2002 completely destroyed the tourist station at Piano Provenzana and part of the tourist station around the Rifugio Sapienza on the south side of the volcano. It took the lava two weeks to reach the station. On July 29th airports of Catania were closed due to ash and the winter tourist industry was affected badly.
MANAGEMENT OF THE HAZARD AND RESPONSES TO THE EVENT
• long history of people living nearby, Etna has much experience of managing eruptions.
• In most instances locals have rebuilt their own properties from salvaged materials or relocated elsewhere, and government intervention has been rare.
• One intervention occurred in 1991-3 when Zafferana was threatened by a lava flow. Initial attempts proved unsuccessful when hastily built earth barriers were surmounted. Instead, explosives were detonated to disrupt and redirect the flow and break up the efficient lava tubing system which had guided it 7km downslope. Later in 2002, dams of soil and volcanic rock were put up to protect the tourist base at Rifugio Sapienza and helped divert the flow. The Army’s heavy earth-moving equipment was also brought in to block the flows. The Italian government pledged immediate financial assistance to losses in tourism and agriculture of more than £5.6m and tax breaks for villagers.
MONITORING:
• The Catania Section of the Instituto Nazionale di Geofiisica e Vulconalogia (INGV) has monitored the volcano for 20 years with a permanent network of remote sensors (seismic, gedetic, magnetic, gravimetric and videos) xonnected in real time, radio and by mobile phone, to the acquisition centre.
• These data are also integrated with discrete observations, surveys and laboratory analysis to evaluate in real time the activity level of the volcano and issue warnings.
• Geochemical monitoring programmes test gas/fluid emissions to help predict new eruptions and warn of emissions. 