Indonesia contains over 130 active volcanoes, more than any other country in the world. They comprise the axis of the Indonesian island arc system, which is formed by subduction of Northeast of Indo-Australian plate. Many of the volcanoes lie along the arc of two largest Island, Java and Sumatra. The Islands are separated by the Sunda Straits. Krakatoa is one of the volcanos on Rakata Island which is in Sundra Straits, and it is located on northeast fault zone. It sat on the hot spot of Pacific ring of fire. Krakatoa has shown a capacity to generate highly explosive eruption then sank into the deep magma. (5)
Early in the morning of May 20, 1883, the German warship’s captain reported seeing cloud of ash and dust rising above the island of Krakatau which the eruption had happened once ,two century ago. Over two months, crews on ships would experience similar spect
acles, all of which were associated with a mild detonation. On August 27, the volcano entered the final stage of its eruption. Four enormous eruptions took place at 5.30AM, 6.42AM, 8.20AM, 10.02AM, the last one was the worst and loudest. Each eruption was followed by Tsunamis which was about 100 ft high. Large areas of Sundra Strait and Sumatran coast were effect by the flow of lava from the volcano. Around noon, a rain of hot ashes fell around Ketimbang in Sumatra.
The Krakatau itself caused around thousand people killed. The explosions were very violent that it was heard as far away as Mauritius which was about 4800 km away. It was believed that it was the loudest eruption in History. Ashes are propelled to height of 50 miles. The eruptions stopped rapidly after that point. The volcano went back to sleep by the next day. Small eruption continued through February 1884. After all the island of Krakatau had almost entirely disappeared, leaving behind a 250 meter deep caldera. And then there were the seismic waves or Tsunami. It was believed that Tsunamis was caused by gigantic lava flows entering the sea, each explosive caused a lots of lava flows. It displaced huge volume amount of sea water. Also with the collapse of the volcano, this displaced even more amount of sea water. The tidal waves devastated the inhabited Island of Indonesi
a. Merek, the small Javanese town, was washed away. Ships as far away as countries in South Africa also had effected by Tsunamis. The combined effects of volcanic ashes and tsunamis were disastrous in the region. The Senesi city which was 13 km away from Krakatau, had no survivors from 3000 people. The Ketimbang which was 40 km away from Krakatau, 1000 people survived. The tsunamis killed about 36000 people. Many settlements were devastated. There was report of human skeleton floated on the Indian Ocean on the pumice raft. Land on Java is now a national park. In the year following the eruption, the global temperature fell by 1.2 degree Celsius. Weather patterns are changes for several years. The eruption injected large amount of sulfur dioxide gas which caused high level wind all over the world. This led to increase of the clouds which reflected the sunlight away therefore the planet was cooled down. Everything goes back to normal after the acid precipitation took part. (1,2,3,4,6,7)
Krakatoa sank after 1883. However in 1927, the top of the new volcano, Anak krakatoa, rise and it grew bigger every year. It definitely is going to be exploded. Hopefully, it will not be as violent as what’s happened in 1883. SInce Indonesia is LEDC, it doesn't recover as quick as the MEDCs. However the help from other countries were shown by sending stuff such as food and clothes to the country. Many villages were destroyed, the governemnt must use big amount of the money to help the country as well. (3,6)
1http://www.matter-antimatter.com/krakatoa_volcano.htm
2http://volcano.und.edu/vwdocs/frequent_questions/grp7/asia/question879.html
3http://www.geology.sdsu.edu/how_volcanoes_work/Krakatau.html
4http://dsc.discovery.com/convergence/krakatoa/krakatoa.html
5http://www.earlham.edu/~bubbmi/krakatoa.htm
acles, all of which were associated with a mild detonation. On August 27, the volcano entered the final stage of its eruption. Four enormous eruptions took place at 5.30AM, 6.42AM, 8.20AM, 10.02AM, the last one was the worst and loudest. Each eruption was followed by Tsunamis which was about 100 ft high. Large areas of Sundra Strait and Sumatran coast were effect by the flow of lava from the volcano. Around noon, a rain of hot ashes fell around Ketimbang in Sumatra.
The Krakatau itself caused around thousand people killed. The explosions were very violent that it was heard as far away as Mauritius which was about 4800 km away. It was believed that it was the loudest eruption in History. Ashes are propelled to height of 50 miles. The eruptions stopped rapidly after that point. The volcano went back to sleep by the next day. Small eruption continued through February 1884. After all the island of Krakatau had almost entirely disappeared, leaving behind a 250 meter deep caldera. And then there were the seismic waves or Tsunami. It was believed that Tsunamis was caused by gigantic lava flows entering the sea, each explosive caused a lots of lava flows. It displaced huge volume amount of sea water. Also with the collapse of the volcano, this displaced even more amount of sea water. The tidal waves devastated the inhabited Island of Indonesi
a. Merek, the small Javanese town, was washed away. Ships as far away as countries in South Africa also had effected by Tsunamis. The combined effects of volcanic ashes and tsunamis were disastrous in the region. The Senesi city which was 13 km away from Krakatau, had no survivors from 3000 people. The Ketimbang which was 40 km away from Krakatau, 1000 people survived. The tsunamis killed about 36000 people. Many settlements were devastated. There was report of human skeleton floated on the Indian Ocean on the pumice raft. Land on Java is now a national park. In the year following the eruption, the global temperature fell by 1.2 degree Celsius. Weather patterns are changes for several years. The eruption injected large amount of sulfur dioxide gas which caused high level wind all over the world. This led to increase of the clouds which reflected the sunlight away therefore the planet was cooled down. Everything goes back to normal after the acid precipitation took part. (1,2,3,4,6,7)Krakatoa sank after 1883. However in 1927, the top of the new volcano, Anak krakatoa, rise and it grew bigger every year. It definitely is going to be exploded. Hopefully, it will not be as violent as what’s happened in 1883. SInce Indonesia is LEDC, it doesn't recover as quick as the MEDCs. However the help from other countries were shown by sending stuff such as food and clothes to the country. Many villages were destroyed, the governemnt must use big amount of the money to help the country as well. (3,6)
1http://www.matter-antimatter.com/krakatoa_volcano.htm2http://volcano.und.edu/vwdocs/frequent_questions/grp7/asia/question879.html
3http://www.geology.sdsu.edu/how_volcanoes_work/Krakatau.html
4http://dsc.discovery.com/convergence/krakatoa/krakatoa.html
5http://www.earlham.edu/~bubbmi/krakatoa.htm
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