April 10, 1815 Eruption of Tambora

Ref #2990, p. 10-11, p. 933:

In Sumbawa, 10,000 people were killed in the pyroclastic flows. The ashfall was focused on the west coast and in Lombok and Bali, the ash was so thick that many people were killed immediately when the roofs of their homes collapsed due to the weight of the ash.

The blanket of ash fallout on Sumbawa destroyed all crops, resulting in famine immediately after the eruption. These effects were not restricted to Sumbawa as famine and disease brought about by the eruption was severe on distant islands as well. On Lombok, estimates of the death toll ranged from 44,000 to 100,000 and on Bali at least 25,000. A conservative number of deaths from the eruption and subsequent famine and disease is 117,000.

The eruption emitted large quantities of sulfur dioxide into the atmosphere which caused 1816 to be termed "the year without summer." As average temperatures fell 1 to 2.5 degrees C below normal throughout New England and western Europe.

News of this distant eruption in Indonesia did not reach the Western world for some time, but unusual atmospheric phenomena and climate deterioration set in during 1816—"the year without summer." ...Tambora-size (ca 100 km3 of magna) explosive volcanic eruptions emit large quantities of sulfur dioxide gas into the stratosphere, where it is converted into a sulfuric acid aerosol dust veil that encircles the Earth. The aerosol has the effect of reducing solar heat reaching the surface of the planet, leading to global cooling. Strange atmospheric phenomena had been observed in Europe before the summer of 1816. In May 1815 the sunsets in England were exceptionally colorful, and by September the sky seemed to be on fire every evening. But the spectacular skies brought bad weather the following year, and the year 1816 is the worst on record in Europe, with the mean temperature about 3 deg C below average across the entire continent from Britain in the north to Tunisia in the south. In England the summer was miserable, with the mean temperature for June the lowest on record, or 12.9 deg C. In France it was so cold that the wine harvest was later than at any time since record keeping began--delayed until November in those districts where the grapes were not already frozen on the vine. In Germany crops failed, a situation exacerbated by the war with Napoleon, and famine and price inflation were widespread. Conditions in Germany became so intolerable that people in many districts rioted and set off in search of better living conditions, starting the great migration from northern Europe east to Russia and west to America. The severe weather in fact led to crop failure of all the major crops in Europe and doubling of the price of wheat from 1815 to 1817. When we consider than in the early part of the 19th century agriculture was the mainstay of society, it is clear that the climate change had a strong impact on the economy of the western world.

Ref #2432:

VEI 7, Tephra Volume: 1.6x 1011 m3.

Ref #9675:

Approximately 11,000 direct deaths from bomb impacts, tephra falls, and tsunamis; recent work indicates pyroclastic flows reached all but W coast and probably caused most direct fatalities on Sumbawa.

Indirect effects: An estimated 49,000 persons died of famine and disease on Sumbawa and Lombok islands following the eruption. This replaces an earlier estimate of 82,000.

Ref #14333:

The 1815 eruption of Tambora is mainly known for its global climatic impact due to the ejection of ~ 55 Tg of SO2 and ~ 100 Tg of sulfate aerosols into the atmosphere (Rampino and Self 1982; Self et al. 2004) and its human consequences worldwide (Oppenheimer 2003). The eruption was so devastating in the near field that eyewitness accounts are relatively rare and lacking in detail (Self et al. 1984; Stothers 1984; Oppenheimer 2003).