Abstract
Volcanic eruptions may create a wide range of risks in inhabited areas and, as a consequence, major economic damage to the surrounding territory. An example of volcanic hazard was given between 1998 and 2001 by Mt. Etna volcano, in Italy, with its frequent paroxysmal explosive activity that caused more than a hundred fire-fountain episodes. In the period January–June 2000, in particular, 64 lava fountains took place at the Southeast Crater. During the most intense explosive phase of each episode, a sustained column often formed, reaching up to 6 km above the eruptive vent. Then, the column started to expand laterally causing more or less copious tephra fallout on the slopes of Etna; ash and lapilli, therefore, constituted a serious danger for vehicular and air traffic. A software and hardware warning system was developed to mitigate the volcanic hazard indicating the areas affected by potential ash and lapilli fallout. The alert system was mainly based on the good correspondence between the pattern of volcanic tremor amplitude and the evolution of explosive activity. When a fixed tremor threshold was exceeded, a semiautomatic process started to send faxes to Civil Defence and Municipalities directly affected by tephra fallout, together with information on wind directions from the Meteorological Office. The application of this methodology, during the last 14 eruptive episodes in 2000 and the 14 events occurred in 2001, demonstrated the good correspondence between the forecasts on the areas affected by tephra fallout and the effective tephra distribution on land. Despite the integrity of the performance provided by the alert system, small discrepancies occurred in the technical procedure of alerting, for which possible solutions have been discussed. The improvement of this type of system, could become basic for the Etnean region and be proposed for similar volcanic areas throughout the world.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Aki K, Koyanagi R (1981) Deep volcanic tremor and magma ascent mechanism under Kilauea, Hawaii. J Geophys Res 86:7095–7109
Aki K, Feheler M, Das S (1977) Source mechanism of volcanic tremor: fluid driven crack models and their application to the 1963 Kilauea eruption. J Volcanol Geotherm Res 2:259–287
Alparone S, Privitera, E (2001) Characteristics of the intermittent volcanic tremor at Mt. Etna, Italy, during the 15 September 1998–4 February 1999 eruptive episode. In: Proc. of Cities on Volcanoes 2 Conference, Auckland, New Zealand, 12th–16th February 2001, Earthquake Commission, Inst. Geol. Nucl. Sci. Inf. Ser., vol. 49, Inst. of Geol. And Nucl. Sci. Lower Hutt, New Zealand
Alparone S, Andronico D, Lodato L, Sgroi T (2003) Relationship between tremor and volcanic activity during the Southeast Crater eruption on Mount Etna in early 2000, J Geophys Res 108(B5) 2241, DOI: 10.1029/2002JB001866
Andronico D, Branca S, Calvari S, Burton MR, Caltabiano T, Corsaro RA, Del Carlo P, Garfì G, Lodato L, Miraglia L, Muré F, Neri M, Pecora E, Pompilio M, Salerno G, Spampinato L (2005) A multi-disciplinary study of the 2002–03 Etna eruption: insights for a complex plumbing system, Bull Volcanol 67, 314–330. DOI: 10.1007/s00445-004-0372-8
Beniot JP, McNutt S (1997) New constraints on source processing of volcanic tremor at Arenal Volcano, Costa Rica, using broadband seismic data, Geophys. Res Lett 24:449–452
Chouet B (1981) Ground motion in the near field of a fluid-driven crack and its interpretation in the study of shallow volcanic tremor. J Geophys Res 86:5985–6016
Falsaperla S, Privitera E, Spampinato S, Cardaci C (1994) Seismic activity and volcanic tremor related to the December 14, 1991 Mt. Etna eruption, Acta Vulcanol 4:63–73
Falsaperla S, Alparone S, D’Amico S, Di Grazia G, Ferrari F, Langer H, Sgroi T, Spampinato S (2005) Volcanic tremor at Mt. Etna, Italy, preceding and accompanying the eruption of July–August (2001). Pure Appl Geophys 162(11):2111–2132
Ferrari F (1999) SACS, Software Acquisizione Segnali: un sistema integrato per l’acquisizione e il trattamento dei segnali. Rapporto Tecnico e manuale d’uso, Contratto d’ordine Gruppo Nazionale per la Vulcanologia, prot. No. 2.G/9985.98
Gordeev E (1994) Modelling of volcanic tremor as explosive point sources in a single-layered, elastic half-space. J Geophys Res 98:19687–19703
INGV staff – Sezione di Catania (2001) Multidisciplinary approach yields insight into Mt. Etna 2001 Eruption, EOS Transactions, Am Geophys Union 82(52):653–656
Johnston DM, Houghton BF, Neall VE, Ronan KR, Paton D (2000) Impact of the 1945 and 1995–96 Ruapehu eruptions, New Zealand: an example of increasing societal vulnerability. Geol Soc Am Bull 112:720–726
Julian BR (1994) Volcanic tremor: nonlinear excitation by fluid flow. J Geophys Res 99:11859–11877
Kubotera A (1974) Volcanic tremors at Aso volcano. Dev Solid Earth Geophys 6:29–47
McNutt SR (1994) Volcanic tremor from around the world: 1992 update. Acta Vulcanol 5:197–200
Omer GC (1950) Volcanic tremor. Bull Seismol Soc Am 40:175–194
Privitera E, Sgroi T, Gresta S (2003) Statistical analysis of intermittent volcanic tremor associated with the September 1989 summit explosive eruptions at Mount Etna, Sicily. J Volcanol Geotherm Res 120:235–247
Riuscetti M, Schick R, Seidl D (1977) Spectral parameters of volcanic tremor at Etna. J Volcanol Geotherm Res 2:289–298
Sassa K (1935) Volcanic micro-tremor and eruption earthquakes. Mem Coll Sci Kyoto Univ 18:255–293
Schick R (1981) Source mechanism of volcanic tremor. Bull Volcanol 44(3):491–497
Schick R, Riuscetti M (1973) An analysis of volcanic tremor at South-Italian volcanoes. Zeit Geophysik 39:274–262
Scott TB (2004) Results of a reconnaissance trip to Mt. Etna, Italy: the effect of the 2002 eruption of Etna on the province of Catania. Bull NZ Soc Earthq Eng 37(2):47–61
Seidl D, Schick R, Riuscetti M (1981) Volcanic tremors at Etna: a model for hydraulic origin. Bull Volcanol 44:43–56
Shima M (1958) On the second volcanic microtremor at volcano Aso. Bull Disaster Prev Res Inst Kyoto Univ 19:11–56
Sparks RSJ, Bursik M, Carey S, Gilbert J, Glaze L, Sigurdsson H, Woods AW (1997) Volcanic Plume, Chichester, John Wiley & Sons, Inc., England, 574 pp
Steinberg GS, Steinberg AS (1975) On possible causes of volcanic tremor. J Geophys Res 80:1600–1604
Acknowledgements
We wish to thank Prof. Villari who proposed and discussed the problems of tephra fallout and correct alerting systems. Eugenio Privitera gave us precious support during the first months in which the alert system was tested. Alessandro Bonaccorso generously offered to help us by revising an early version of the manuscript. Special thanks are due to the Meteorological Office of Sigonella for providing information on wind conditions. We gratefully acknowledge Matthew Patrick and an anonymous reviewer for their constructive reviews of the manuscript and for greatly improving the English.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Alparone, S., Andronico, D., Sgroi, T. et al. Alert system to mitigate tephra fallout hazards at Mt. Etna Volcano, Italy. Nat Hazards 43, 333–350 (2007). https://doi.org/10.1007/s11069-007-9120-7
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11069-007-9120-7