Mount Tambora Volcano Eruption - Largest in modern historyMount Tambora experienced several centuries of inactive dormancy before 1815, as the result of the gradual cooling of hydrous magma in a closed magma chamber. Inside the chamber at depths between 1.5–4.5 km (4,900–15,000 ft), the exsolution of a high-pressure fluid magma formed during cooling and crystallisation of the magma. Overpressure of the chamber of about 4–5 kbar was generated, and the temperature ranged from 700–850 °C (1,292–1,562 °F). In 1812, the caldera began to rumble and generated a dark cloud. On 5 April 1815, a moderate-sized eruption occurred, followed by thunderous detonation sounds, heard in Makassar on Sulawesi (380 kilometres or 240 mi), Batavia (now Jakarta) on Java (1,260 km or 780 mi), and Ternate on the Molucca Islands (1,400 km or 870 mi). What was first thought to be sound of firing guns was heard on 10–11 April on Sumatra island (more than 2,600 km or 1,600 mi away). On the morning of April 6, volcanic ash began to fall in East Java with faint detonation sounds lasting until 10 April. At about 7 p.m. on 10 April, the eruptions intensified. Three columns of flame rose up and merged. The whole mountain was turned into a flowing mass of "liquid fire". Pumice stones of up to 20 centimetres (7.9 in) in diameter started to rain down at approximately 8 p.m., followed by ash at around 9–10 p.m. Hot pyroclastic flows cascaded down the mountain to the sea on all sides of the peninsula, wiping out the village of Tambora. Loud explosions were heard until the next evening, 11 April. The ash veil had spread as far as West Java and South Sulawesi. A "nitrous" odor was noticeable in Batavia and heavy tephra-tinged rain fell, finally receding between 11 and 17 April.
How big was the Tambora Volcano Eruption?
The explosion is estimated to have been at scale 7 on the Volcanic Explosivity Index. It had roughly four times the energy of the 1883 Krakatoa eruption. An estimated 160 cubic kilometers (38 cubic miles) of pyroclastic trachyandesite was ejected, weighing approximately 1.4×1014 kg (see above).This has left a caldera measuring 6–7 km (3.7–4.3 mi) across and 600–700 m (2,000–2,300 ft) deep. The density of fallen ash in Makassar was 636 kg/m². Before the explosion, Mount Tambora was approximately 4,300 metres (14,100 ft) high, one of the tallest peaks in the Indonesian archipelago. After the explosion, it now measures only 2,851 metres (9,354 ft). Largest volcanic eruption in recorded history
The 1815 Tambora eruption is the largest observed eruption in recorded history. The explosion was heard 2,600 kilometres (1,600 mi) away, and ash fell at least 1,300 kilometres (810 mi) away. Pitch darkness was observed as far away as 600 kilometres (370 mi) from the mountain summit for up to two days. Pyroclastic flows spread at least 20 kilometres (12 mi) from the summit. What was the aftermath of the Tambora Volcano? All vegetation on the island was destroyed. Uprooted trees, mixed with pumice ash, washed into the sea and formed rafts of up to 5 kilometres (3.1 mi) across. One pumice raft was found in the Indian Ocean, near Calcutta on 1 and 3 October 1815. Clouds of thick ash still covered the summit on 23 April. Explosions ceased on 15 July, although smoke emissions were still observed as late as 23 August. Flames and rumbling aftershocks were reported in August 1819, four years after the event. A moderate-sized tsunami struck the shores of various islands in the Indonesian archipelago on 10 April, with a height of up to 4 metres (13 ft) in Sanggar at around 10 p.m. A tsunami of 1–2 m (3.3–6.6 ft) in height was reported in Besuki, East Java, before midnight, and one of 2 metres (6.6 ft) in height in the Molucca Islands. The total death-toll has been estimated at around 4,600 . The eruption column reached the stratosphere, an altitude of more than 43 km (140,000 ft). The coarser ash particles fell 1 to 2 weeks after the eruptions, but the finer ash particles stayed in the atmosphere from a few months up to a few years at an altitude of 10–30 km (33,000–98,000 ft). Longitudinal winds spread these fine particles around the globe, creating optical phenomena. Prolonged and brilliantly colored sunsets and twilights were frequently seen in London, England between 28 June and 2 July 1815 and 3 September and 7 October 1815. The glow of the twilight sky typically appeared orange or red near the horizon and purple or pink above. What was the death toll of the Tambora eruption?
The estimated number of deaths varies depending on the source. Zollinger (1855) puts the number of direct deaths at 10,000, probably caused by pyroclastic flows. On Sumbawa island, there were 38,000 deaths due to starvation, and another 10,000 deaths occurred due to disease and hunger on Lombok island. Petroeschevsky (1949) estimated about 48,000 and 44,000 people were killed on Sumbawa and Lombok, respectively. Several authors use Petroeschevsky's figures, such as Stothers (1984), who cites 88,000 deaths in total. However, Tanguy et al.. (1998) claimed Petroeschevsky's figures to be unfounded and based on untraceable references. Tanguy revised the number solely based on two credible sources, q.e., Zollinger, who himself spent several months on Sumbawa after the eruption, and Raffles's notes. Tanguy pointed out that there may have been additional victims on Bali and East Java because of famine and disease. Their estimate was 11,000 deaths from direct volcanic effects and 49,000 by post-eruption famine and epidemic diseases. Oppenheimer (2003) stated a modified number of at least 71,000 deaths in total. |
