Lava flow hazard at Mount Etna (Italy): New data from a GIS-based study
Invasion of inhabited areas and destruction of human property by lava flows represents the greatest volcanic hazard at Mount Etna (Italy) in the short term, based on the character of the historically documented eruptions of the volcano. Virtually all eruptions of Etna produce lava flows, which are more likely to cause damage when emitted from flank vents. Since A.D. 1600, more than sixty eruptions have occurred on the flanks of Etna. About half of these caused damage to, or destruction of, human property, dwellings, and infrastructures, and at least two destroyed entire population centers. We present a quantitative analysis and evaluation of a new database containing numerical volcanological parameters of each post-1600 eruption, which allows us to quantify the hazard possible from future eruptions and to create a preliminary hazard zonation map divided into six zones. A total area of nearly 1400 km2 is considered vulnerable, which is home to >900,000 people. The greatest hazard is from voluminous and/or low-altitude flank eruptions, which during the historical period have occurred at irregular intervals of 120–400 yr, the most recent in 1669. In the future, eruptions at higher elevations will occur much more frequently, at intervals of a few months to several decades, and many will cause damage in relatively limited areas. A recent increase in the intensity and frequency of eruptions indicates that the Etna volcanic system is presently more dynamic than during the past 330 yr, and low-altitude flank eruptions have to be considered a realistic possibility for the near future.