Based on visual observations and seismic data, CVGHM raised the Alert Level for Tambora to 2 (on a scale of 1-4) on 5 April.

All times are local (= UTC - 9 hours [or 8 hours early April-late October])

2013: April |
2012: April |
2011: August | September | October |

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3 April 2013              Back to Top

Based on visual observations and seismic data, CVGHM raised the Alert Level for Tambora to 2 (on a scale of 1-4) on 5 April.

Sources: Center of Volcanology and Geological Hazard Mitigation (CVGHM)

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4 April 2012              Back to Top

CVGHM reported that during January-8 April plumes did not rise from Tambora, no changes were observed around the caldera, and seismicity decreased. On 9 April the Alert Level was lowered to 1 (on a scale of 1-4).

Sources: Center of Volcanology and Geological Hazard Mitigation (CVGHM)

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12 October 2011              Back to Top

CVGHM reported that during 22 September-9 October plumes did not rise from Tambora; seismicity fluctuated, but declined overall. Based on visual observations, deformation data, and seismicity, the Alert Level was lowered to 2 (on a scale of 1-4) on 9 October.

Sources: Center of Volcanology and Geological Hazard Mitigation (CVGHM)

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7 September 2011              Back to Top

Based on visual observation and seismic data, CVGHM reported an increase in activity at Tambora that started in April. Therefore, on 30 August, the Alert Level was raised to 2 (on a scale of 1-4). During 30 August-8 September seismicity continued to increase. Diffuse white plumes were observed on 5 September and rose 10 m above the crater rim. On 8 September the Alert Level was raised to 3 (on a scale of 1-4).

Sources: Center of Volcanology and Geological Hazard Mitigation (CVGHM)

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24 August 2011              Back to Top

Based on visual observation and seismic data, CVGHM reported an increase in activity at Tambora during the previous five months. Ground-based observers at an observation post in Tambora village noted dense white plumes rising 50-75 m above the caldera rim during April and June, but no plumes during May or July. In August dense white plumes rose 20 m above the caldera rim. Seismicity started to increase in April and continued to increase through August. On 30 August the Alert Level was raised to 2 (on a scale of 1-4).

Sources: Center of Volcanology and Geological Hazard Mitigation (CVGHM)

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Below is a summary of eruption dates and Volcanic Explosivity Indices (VEI).

The following references are the sources used for data regarding this volcano. References are linked directly to our volcano data file. Discussion of another volcano or eruption (sometimes far from the one that is the subject of the manuscript) may produce a citation that is not at all apparent from the title. Additional discussion of data sources can be found under Volcano Data Criteria.

Barberi F, Bigioggero B, Boriani A, Cattaneo M, Cavallin A, Cioni R, Eva C, Gelmini R, Giorgetti F, Iaccarino S, Innocenti F, Marinelli G, Slejko D, Sudradjat A, 1987. The island of Sumbawa: a major structural discontinuity in the Indonesia arc. {Bol Soc Geol Italy}, 106: 547-620

Cole-Dai J, Ferris D, Lanciki A, Savarino J, Baroni M, Thiemens M H, 2009. Cold decade (AD 1810-1819) caused by Tambora (1815) and another (1809) stratospheric volcanic eruption. {Geophys Res Lett}, 36: L22703, doi:10.1029/2009GL040882

Foden J, 1986. The petrology of Tambora Volcano, Indonesia: A model for the 1815 eruption. {J Volc Geotherm Res}, 27: 1-41

Neumann van Padang M, 1951. Indonesia. {Catalog of Active Volcanoes of the World and Solfatara Fields}, Rome: IAVCEI, 1: 1-271

Self S, Rampino M R, Newton M S, Wolff J A, 1984. Volcanological Study of the Great Tambora eruption of 1815. {Geology}, 12: 659-663

Sigurdsson H, Carey S, 1989. Plinian and co-ignimbrite tephra fall from the 1815 eruption of Tambora volcano. {Bull Volc}, 51: 243-270

Sigurdsson H, Carey S, 1992. Eruptive history of Tambora volcano, Indonesia. {In}: Degens E T, Wong H K, Zen M T (eds) {The Sea off Mount Tambora}, Mitteilschen Geol-Palaont Inst Univ Hamburg, 70: 187-206

Stothers R B, 1984. The great Tambora eruption in 1815 and its aftermath. {Science}, 224: 1191-1198

Varne R, Foden J D, 1986. Geochemical and isotopic systematics of eastern Sunda arc volcanics; implications for mantle sources and mantle mixing processes. {In}: F-C Wezel (ed), {The Origin of Arcs}, Amsterdam: Elsevier, 159-189

The massive Tambora stratovolcano forms the entire 60-km-wide Sanggar Peninsula on northern Sumbawa Island. The largely trachybasaltic-to-trachyandesitic volcano grew to about 4000 m elevation before forming a caldera more than 43,000 years ago. Late-Pleistocene lava flows largely filled the early caldera, after which activity changed to dominantly explosive eruptions during the early Holocene. Tambora was the source of history's largest explosive eruption, in April 1815. Pyroclastic flows reached the sea on all sides of the peninsula, and heavy tephra fall devastated croplands, causing an estimated 60,000 fatalities. The eruption of an estimated more than 150 cu km of tephra formed a 6-km-wide, 1250-m-deep caldera and produced global climatic effects. Minor lava domes and flows have been extruded on the caldera floor at Tambora during the 19th and 20th centuries.