Tambora

Eruption of Tambora

The April 5th 1815 there was a first eruption giving a 33 km height eruptive column and which lasted 33 hours. People did not leave their house. During the days which followed the volcano remained in a basic state activity. April 6th, a light fall of ashes made include/understand with the inhabitants of Batavia (Jakarta today, with: 1260 km of the volcano) that the heard detonations the day before, which had justified the sending of military patrols per fear of an attack, were of volcanic origin.

The paroxysm of the eruption took place later 5 days, on April 10th. Towards 10:00 of the morning, a 44 height km eruptive column went up in the sky but the eruption lasted only 3:00. Towards 7:00 of the afternoon, the activity of the volcano increased, followed one hour later of a rain of pounce on the village of Sanggar, 30 km in the east. The volcano at this time was then surmounted according to the witnesses of three “columns of flames”, makes three eruptive columns of them. The stone pounces fall lasted until 10:00 of the evening when the village of Sanggar was devastated by a shock wave. About this moment, always according to the witnesses, the three columns amalgamated and the mountain was nothing any more but one mass of “liquid fire”. That corresponds to the widening of the conduit of emission of to the important eruptive flow and at the first stages of the formation of will caldeira. Consequently, the eruptive column was blocked out of matters and ends up crumbling, creating several pyroclastic castings of overheated gases, Cendres and stones pounces which gave place to deposits of ignimbrite. One counted 7 of them which was spread out radially around the volcano and penetrated in the sea up to 40 km of distance from the top of the volcano. These pyroclastic castings launched in the sea generated there secondary explosions increasing the volume of ashes dispersed in the atmosphere until representing the independent source of volcanic ash of the eruption. April 12th, whereas the eruption continued, the eruptive sunshade had extended so much so that to 900 km from there in Java whereas resounded with far the explosions, the first gleams of the day appeared only with 10:00 and that it is only with 11:00 that the birds are reflected to sing. It is only on April 15th that the eruption ceased and on April 17th that the falls of ash, which extended until: 1300 km of distance, ceased leaving a landscape devastated on the peninsula of Sanggar.

The eruption had a power estimated at 8 times that of the eruption of the Vesuvius, that is to say more than one hundred times the bombs of Hiroshima and joined together Nagasaki. The explosions were heard with more: 1400 km of distance.

After with the expulsion so much of magma, the remainder of the mountain crumbled on itself, and formed large a will caldeira 6 km in diameter and 1 km of depth, thus decreasing the altitude of the volcano of: 1400 meters.

tidal wave fell down on the islands several hundred away kilometers. The volcanic activity killed directly: 11000 people. With these victims those of the tsunamis and those of the famine and the epidemics were added which prevailed on Sumbawa and Lombok and which killed: 49000 people. On the whole, the eruption seems to have killed between: 61000 and: 71000 people.

Climatic consequences

The ash sent in the Stratosphère made several times it tower of the Earth, causing, at the beginning of the summer, of splendid sunsets rougeoyants, painted by the painter William Turner: to see Didon building in particular Carthage (or birth of the Carthaginian Empire) , 1815, National Gallery, London.

In 1816, the average temperatures in the Northern Hemisphere went down from 0,5 to more 1°C. The farmers of Europe and North America called this year the year without summer.

This eruption was the most violent volcanic eruption never known historically, and especially most fatal of the Histoire, much stronger than that of the Vesuvius and yet much less famous (not to say unknown).

The quantity of emitted matter was of 150 km ³ and was much more important than for the Krakatoa and the Vesuvius.

The eruption has affected oceans and Tropique S, and all the records of fall of temperature were beaten in 1815 and 1816.

This catastrophe was at the origin of “frozen summers”:

the “summer without sun” of 1815 in New England, caused by the blocking of the solar rays by the sulfur particles distributed in the atmosphere and the Stratosphere;
the summer 1816, coldest ever recorded in Europe (in the countries equipped with a reliable weather), was at the origin of a Famine which made more: 200000 victims in Europe.

The the Alps Suisse S were particularly touched so much so that during the summer 1816, it snowed there almost every week.

Continuations on the spot

The vulcanologist Haraldur Sigurðsson studied thoroughly this eruption, during more than 20 years.

During a difficult forwarding, it is descended in the Caldeira from the volcano. The descent with the vertical required one half-day.

On the old site of the village, using scanners it could find remainders of dwellings and carbonized skeletons buried in the Cendres.

Current research

Today the research carried out on this eruption is of great importance, because they help to distinguish the natural climate changes from those created by the man.

Many testimonys of the climate changes were made by various people. Michael Chenoweth studied the log books of the British marine of the time, and those of the captain of the ship inconstant the which made very precise statements. The US president Thomas Jefferson observed in a precise way all these climate changes.

Documentary

a video production of Tetra Media in partnership with France 2 was carried out on this subject.
documentary interesting, a summer without sun , was diffused on Arte on November 4th, 2006 with 20:40.

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