1. Mount Tambora Explosion By Nathan Walker Group 84

2. When and Where? The eruption of Mount Tambora happened in Indonesia in 1815. The volcano, one of Indonesia’s largest, is located on the island of Sumbawa, near Bali and Lombak.

3. Where do Volcanoes Form? Volcanoes almost always form on plate boundaries. With a few exceptions, like Hawaii, most volcanoes are along a plate boundary of continental and oceanic crust. The red dots on the diagram below show where volcanoes are located.

4. What kind of volcano? Mount Tambora is a composite volcano or stratovolcano. It consists of rock layers such as hardened lava, pumice, and ash. The volcano was 13,000 feet tall before the devastating explosion, but only 9,000 feet of it was left after the eruption.

5. How Are They Formed? Volcanoes are formed when oceanic crust collides with continental crust, causing an event scientists call subduction (below). Subduction is the melting of the oceanic plate, and having that melted crust vent through the earth’s surface, forming a volcano.

6. The Eruption There were very few signs that the volcano was about to erupt. Flames of about 40 km tall were seen being spewed into the atmosphere. A huge column of wind carried people and their houses out to sea, where there were 5m high tsunamis.

7. Deaths A final death toll for the eruption was over 92,000. 10,000 people died from direct burns, which is similar to what happened in Pompeii. Another 82,000 people in Indonesia died, the people of Tambora made extinct, and 25,000 more dead in nearby Bali, a total of about 117,000 deceased.

8. Year Without Summer The devastating eruption caused a “year without summer” due to climate changes in the Northern Hemisphere. It affected so many countries, sending some to states of national emergency. The next few slides tell how countries were affected.

9. Switzerland, 1816 In Switzerland in 1816, the effects of the volcanic eruption all the way in Indonesia a year before caused plants to become poisonous. The government issued a lesson on how to tell poisonous plants from safe plants, and the Swiss eventually resorted to eating plain moss.

10. Sumbawa, Indonesia Sumbawa was covered by a 60 cm thick coat of fallen ash, leading to massive famine. Bali, Lombak, and South Sulawesi were covered in a 30 cm coat of ash. This completely submerged the plants, leading to the fatal famine.

11. Citations 33ff.com. N.p., n.d. Web. 16 Mar. 2011.. The World According to Google. N.p., n.d. Web. 15 Mar. 2011.. “Year Without Summer.” Discovery Education. N.p., n.d. Web. 15 Mar. 2011. <http://www.yourdiscovery.com/‌earth/‌year_without_summer/‌pre_eruption/‌index http://2.bp.blogspot.com/_w5VUS6vQlII/S7H- Wdwp94I/AAAAAAAAACw/UNRnYhcGbjs/s1600/darkness.jpg http://www.worldatlas.com/aatlas/infopage/ringfire.gif

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