Photo at left shows the unique outcrop of 1669 lava at Castello Ursino, in the southern part of the city of Catania. The pre-1669 ground surface has been excavated on the southwestern corner of the Castello, revealing a section through the lava flow which surrounded the building and buried it to about one-third of its height, but did not damage it. It even withstood the devastating earthquake of 1693 that leveled most of Catania, killing two-thirds of its inhabitants

Etna and Man (2)

A CHRONOLOGY OF ENCOUNTERS BETWEEN MAN AND ETNA

There have been many unpleasant encounters between Man and the mountain, and most have been caused by eruptions. This is a chronology of the most important of these encounters that will focus on the effects on humans of these events rather than on the course of the eruptions themselves. The first section deals with events that have killed, or are said to have killed people.

DEATHS
While two cases of alleged fatalities caused by Etna (1169 and 1669) have been discussed more broadly on the previous page, it is appropriate to take a closer look at those events that did produce victims and review others reported in the literature as fatal eruptions. Here I provide an analysis of all eruptions listed as fatal, with the aim to correct the false impression of Etna as a particularly deadly volcano, and to pinpoint the situations that might result in real danger to life or health.

• 141 B.C. or 140 B.C. - 40 repordedly killed by an eruption. Lack of any further detail precludes an interpretation of the precise circumstances of this incident. Interpretation: DOUBTFUL
• 1169 - Numerous fatalities (possibly up to 15,000) produced by a tectonic earthquake, not by an eruption. An eruption reported for the same year is doubtful. Interpretation: NO DEATHS
• 1329 (15 July) - "Many people killed" from terror at beginning of an eruption on the lower southeastern flank, near Monterosso. This report appears to be somewhat doubtful to me since I know of very few eruptions to have produced deaths by terror. Interpretation: DOUBTFUL
• 1536 (26 March) - 1 person killed, possibly near an active crater, by falling stones. This sounds credible because other similar incidents have occurred more recently. Interpretation: 1 PERSON KILLED
• 1669 (March-July) - Up to 20,000 fatalities attributed to this eruption, but it is likely that here the effects of the eruption and the devastating effects of the 1693 tectonic earthquake were confused. On the other hand, an eruption reported to have accompanied the 1693 earthquake is highly doubtful. Interpretation: NO DEATHS
• 1689 (March) - 4 people killed by blocks falling from the front of a lava flow in the area of the Valle del Bove while watching the advance of the flow. Interpretation: 4 PEOPLE KILLED
• 1832 (November?) - Several people killed by a steam explosion provoked by lava flowing over ice field. I have found no reference to fatalities caused by this explosion which is reported in contemporary eyewitness accounts. These would have certainly mourned the dead, as was the case in the incident eleven years later. Interpretation: NO DEATHS
• 1843 (25 November) - A sudden steam explosion, possibly produced by the instantaneous evaporation of a water body trapped under flowing lava, killed 59 people who had watched the advance of the lava near the town of Bronte. This event is well documented by Gemmellaro (1843) who also gave a complete list of the names of the victims. Interpretation: 59 PEOPLE KILLED
• 1928 (7 November) - Up to 5 people reported killed by the lava flow that destroyed the town of Mascali. A recent study by Duncan et al. (1996) has shown that there were no deaths. Contemporary Italian newspaper reports emphasize on the fact that "the lava at least gives the people the time not only to save their lives, but also to salvage most of their households". Interpretation: NO DEATHS
• 1929 (2 August) - 2 young men killed by a sudden explosion at Northeast Crater whose causes are uncertain. It is possible that this event was similar to those of 1979 and 1987. Interpretation: 2 PEOPLE KILLED
• 1979 (12 September) - 9 tourists killed and many others injured by a sudden explosion at Bocca Nuova. While the causes and mechanisms of this explosion have been subject to debate, the event had serious repercussions on tourism-related policies on Etna. It also showed the discrepancies between diverse groups of scientists working on the volcano. Now it is known that Etna produces frequently such violent explosions in inter-eruptive periods, that is, between one cycle of magmatic activity and another. It appears that the summit area is especially dangerous in the first year after the end of a magmatic eruption, and unfortunately yet another incident of this kind occurred after the 1979 event. Interpretation: 9 PEOPLE KILLED
• 1987 (15 April) - A sudden explosion at Southeast Crater killed 2 tourists and injured several others. Like in 1979, a major magmatic eruption had ended only six weeks earlier. Interpretation: 2 PEOPLE KILLED

The total number of confirmed deaths produced by Etna in more than 2000 years is thus 77 while an unknown number of people may have been killed in other eruptions which are not or poorly documented. Etna is thus anything else but the killer volcano as described in many general texts, and one also needs to consider that it has been densely inhabited since millennia, and there have always been many people visiting the sites of eruptions, exposing themselves to some risk.

In various other cases it was simply luck that nobody was killed or injured when powerful eruptions occurred in the summit area of Etna. Maybe the most dramatic situation was lived by about a dozen volcanologists from various countries who worked near the summit craters on 24 September 1986 when the Northeast Crater produced an unusually violent phreatomagmatic eruption. The still-more violent magmatic eruption of the Southeast Crater on 5 January 1990 occurred during a blizzard in Etna's summit area, and nobody observed the event which was among the most intense summit eruptions of Etna in recent centuries. During the summit eruptions of 1995-2001 there were several events that did not kill anybody only because no one was there, either because the weather was bad or they occurred at night and/or during the winter. The largest event during this period, the 22 July 1998 eruptive paroxysm from the Voragine, had been preceded by activity as intense as to keep tourists from approaching too close to the crater. A similar paroxysm at the same crater on 4 September 1999 occurred during tremendously bad weather, yet there were several groups of people in the summit area who managed to escape unharmed. In other cases it rather seems a miracle that there were no fatal incidents such as during the impressive series of 66 paroxysmal eruptive episodes at the Southeast Crater in 2000.

Two principal facts are highlighted by the preceding chronology of fatal incidents on Etna. First, Etna has never been responsible of disasters with high death-tolls such as Vesuvio or other predominantly explosive volcanoes. Second, in all cases where a relatively precise evaluation of the circumstances of death is possible, those killed were either very close to the erupting vents or near a lava flow that buried water-soaked ground or a small water reservoir, causing the flashing of water into steam and thus generating a violent explosion. The victims were thus in areas of danger and could have been aware of this, even though the tourists who died in 1979 and 1987 were surely not informed about the risk.

It is to be hoped that luck will not run out on Etna as the volcano will continue to produce vigorous, and sometimes unexpected, eruptions in its summit area, and at the same time tourists, journalists and geologists will continue to stream to that same area to expose themselves more or less consciously to a risk that is difficult to calculate.

DAMAGE
We have seen that Etna is clearly not a killer volcano. Neither is it an evil volcano that devours villages and towns on as many occasions as possible. It is true that many of its eruptions cause damage, at times even extensive damage, but it is surprising to see how rarely entire population centers have been wiped out by lava flows in recent centuries. After the truly devastating 1669 eruption, which destroyed fifteen villages before the city of Catania was assaulted and partially destroyed by a huge lava flow, only one eruption led to the complete destruction of a village. This eruption occurred in November 1928 and the victim was Mascali, a quiet village of about 8000 inhabitants on the lower E flank of the volcano. While to the residents the event meant the loss of their homes and of their original habitat, it also brought some benefits that were due to the political situation at that time (the Fascist era of Mussolini) and the need to show the efficiency of the government in providing help for the stricken population. Mascali was rebuilt within ten years, and the new town offered a life standard to the inhabitants that was foreign to those of any other Sicilian village.

The historical record is useful in providing information on the true amount of damage caused by Etna's eruptions since 1600, before that year many documents are not reliable enough to render an authentic idea of the events, the dates on which they took place, and their effects. From the record of the past 400 years it is clear that the 17th century (through 1669) was characterized by an unusually intense eruptive activity with several large eruptions that produced voluminous and damaging lava flows. Extensive areas of forest were buried under a lava flow on the SW flank in 1610. From 1634 until 1638 lava was emitted from a fissure on the SE flank and threatened the villages of Zafferana and Fleri, besides destroying precious areas of fertile ground above these villages. A major eruption in 1646-1647 on the NNE flank built a large pyroclastic cone (Monte Nero) and emitted lava flows that caused significant damage to agricultural areas on the lower N flank, possibly including the destruction of small population centers. In 1651-1653 a long-lived eruption on the W flank produced an extensive lava flow field (much of which consists of pahoehoe lava, which is a relatively uncommon lava type on Etna). The farthest lava fronts advanced close to the town of Bronte and eventually destroyed part of it.

The series of destructive eruptions in the 17th century culminated with the March-July 1669 eruption whose effects have already been described above. In fact this was the most devastating eruption of Etna during the past 2000 years, due to the low elevation of its main vents (the Monti Rossi cone at about 850 m altitude near the town of Nicolosi) and the exceptionally high mass eruption rates (80-100 cubic meters of lava per second). After that event, Etna produced only few and relatively harmless flank eruptions for nearly 100 years. Although one of these, in 1689, is mentioned in some sources to have caused the destruction of a small village, this information seems to be false, for no lavas have been found in the area of the alleged destruction which can be correlated with the eruption date.

The first eruption after 1669 to cause significant damage occurred in 1766 on the S flank (Monti Calcarazzi). Lava flows emitted during this eruption destroyed forests and cultivated land above Nicolosi and threatened the village itself, but the most advanced flow fronts stopped at a distance of 3 km from Nicolosi. A smaller eruption in 1780 on the SW flank destroyed areas of forest. In 1792-1793 lava flows emitted from a fissure on the SE flank seriously threatened Zafferana and destroyed forests and vineyards on the slopes above that village. Then 40 years elapsed before lava again threatened a population center and caused damage to agricultural areas: this eruption occurred in 1832 on the W flank and the besieged village was Bronte. Nearly the same area was again invaded by a lava flow in 1843, which, however, did not directly threaten Bronte, but it destroyed fruit gardens and obtained tragic fame for the death of 59 people when the lava covered a cistern and caused the explosive evaporization of its water content. In 1852-1853, an eruption in the Valle del Bove (Monti Centenari) produced lava flows that threatened the villages of Milo and Zafferana. In 1865 lava flows from the Monti Sartorio (or Monti Sartorius) on the NE flank destroyed forests and fruit gardens. Fourteen years later, in 1879, a violent eruption on the NNE flank emitted a lava flow which extended nearly to the Alcantara river, threatened several hamlets and destroyed fruit gardens and vineyards. Lava emitted from Monte Gemmellaro on the S flank in 1886 came extremely close to Nicolosi (a part of the town has expanded onto that lava in recent years), and the veil of the patron saint of Catania, Sant'Agata, was carried to the lava front in order to halt its advance - this is the latest of the miracles attributed to the veil, for the lava flow stopped short of the village. Six years later, the Monti Silvestri eruption on the same flank again sent out lava flows in the direction of Nicolosi, which, however, did not approach as close as those of 1886.

During the 20th century Etna produced more flank eruptions than in any of the preceding three centuries, and at the same time the population around the volcano grew in an exponential manner, rendering the whole area more and more vulnerable. As a consequence, 13 of the 23 flank eruptions of that period caused damage, threatened population centers, and destroyed other structures such as roads, bridges, railroads and isolated buildings, and vast areas of cultivated land. The 1928 eruption, as mentioned above, destroyed the village of Mascali. Since 1971, damage was caused by eruptions in 1971, 1979, 1981, 1983, 1985, 1989, 1991-1993, and 2001, and population centers were seriously threatened in 1971, 1979, 1981 and 1991-1993. The development of a large complex of tourist facilities on the S flank since the late 1950s rendered this area much more vulnerable to the effects of eruptions, and the cable car (built for the first time sometime around 1958) was destroyed in 1971, rebuilt at lower altitude, again partially destroyed in 1983 and further damaged in 1985, rebuilt and once more partially destroyed in 2001.

It is clear from this summary that the potential of destruction has increased with time due to the expansion of population centers and countless isolated buildings (of which many weekend homes and restaurants) on the flanks of the volcano. The volcano itself is not to blame for these unpleasant encounters, it has always been there since the dawn of humanity and Man had enough time to see and understand that this was an active volcano and that it erupted frequently. If Etna's eruptions are becoming more and more dangerous and destructive, this is the result of a choice made by the people who have built their homes ever closer to the volcano, often illegally and neglecting the value of a natural environment of incredible grandeur and beauty. The volcano is not an evil creature willing to take revenge, it simply does what the physical laws of this planet force it to do. Yet the presence of more than one million people on its slopes and of all of their possessions is a fact that cannot be ignored by this kind of reasoning. There is an urgent need to coordinate the co-existence between these people and the volcano, to understand of what kind future encounters of Man and the volcano might be, and to develop contingency plans for future emergencies which, under the given conditions, will inevitably occur on numerous occasions.

PAGE THREE:
VOLCANIC HAZARDS - WHAT IS ETNA CAPABLE OF?

Copyright © Boris Behncke, "Italy's Volcanoes: The Cradle of Volcanology"