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Laki or Lakagígar (''Craters of Laki'') is a volcanic fissure in the south of Iceland, not far from the canyon of Eldgjá and the small village of Kirkjubæjarklaustur. Lakagígar is the correct name, as Laki mountain itself did not erupt, as fissures opened up on each side of it. Lakagígar is part of a volcanic system centered on the Grímsvötn volcano and including the Þórðarhyrna volcano.〔(【引用サイトリンク】 Iceland : Katla Volcano )〕 It lies between the glaciers of Mýrdalsjökull and Vatnajökull, in an area of fissures that run in a southwest to northeast direction. The system erupted over an eight-month period between 1783 and 1784 from the Laki fissure and the adjoining Grímsvötn volcano, pouring out an estimated of basalt lava and clouds of poisonous hydrofluoric acid and sulfur dioxide compounds that killed over 50% of Iceland's livestock population, leading to a famine which then killed approximately 25% of the island's human population.〔Gunnar Karlsson (2000), ''Iceland's 1100 Years'', p. 181〕 The Laki eruption and its aftermath caused a drop in global temperatures, as sulfur dioxide was spewed into the Northern Hemisphere. This caused crop failures in Europe and may have caused droughts in India. The eruption has been estimated to have killed over six million people globally,〔(How The Earth Was Made: The Age of Earth ) (video), History.com〕 making it the deadliest in historical times. ==1783 eruption== On 8 June 1783, a fissure with 130 craters opened with phreatomagmatic explosions because of the groundwater interacting with the rising basalt magma. Over a few days the eruptions became less explosive, Strombolian, and later Hawaiian in character, with high rates of lava effusion. This event is rated as 6 on the Volcanic Explosivity Index, but the eight-month emission of sulfuric aerosols resulted in one of the most important climatic and socially repercussive events of the last millennium.〔Brayshay and Grattan, 1999; Demarée and Ogilvie, 2001〕 The eruption, also known as the Skaftáreldar ("Skaftá fires") or Síðueldur, produced an estimated of basalt lava, and the total volume of tephra emitted was . Lava fountains were estimated to have reached heights of . The gases were carried by the convective eruption column to altitudes of about . The eruption continued until 7 February 1784, but most of the lava was ejected in the first five months. Grímsvötn volcano, from which the Laki fissure extends, was also erupting at the time, from 1783 until 1785. The outpouring of gases, including an estimated 8 million tons of hydrogen fluoride and an estimated 120 million tons of sulfur dioxide, gave rise to what has since become known as the "Laki haze" across Europe. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Laki」の詳細全文を読む スポンサード リンク
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